LX Series Heat Pump Unit Controller User’s Guidecgproducts.johnsoncontrols.com/MET_PDF/12011484.pdf · LX Series Heat Pump Unit Controller User’s ... 82 Heartbeat Alarms ... LX

LX Series Heat Pump Unit ControllerUser’s Guide

Code No. LIT-12011484Issued June 22, 2009

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Feature Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Sensor Configuration Wizard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Control Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

LonMark Functional Profile. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Units in LONWORKS Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Language Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Selecting a Measurement System or Selecting a Language . . . . . . . . . . . . . . . . . . . . . 16

Heat Pump Unit Controller Installation Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

10k Ohm or Digital Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Analog Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

4 to 20 mA Analog Input, Externally Supplied . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Sensors and Switches. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Auxiliary Alarm Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Bypass Contact Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Coil Differential Pressure Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Coil Frost Contact Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Discharge Temperature Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Emergency Contact Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Fan Speed Selector Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Fan State Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Mode Selector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Occupancy Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Outdoor Temperature Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

1LX Series Heat Pump Unit Controller User’s Guide

Pump State Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Refrigerant Temperature Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Setpoint Offset Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Space Humidity Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Space Temperature Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Water Temperature Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Window Contact Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Analog Output Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Digital Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Staged Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Output Selections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Fan Speed 1 - 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Heating Outputs 1 - 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Cooling Outputs 1 - 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Reversing Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Humidifier and Dehumidifier Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Mode Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Network Variables Used for Mode Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Occupied Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Starting Occupied Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Ending Occupied Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Unoccupied Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Starting Unoccupied Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Ending Unoccupied Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Bypass Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Starting Bypass Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Ending Bypass Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Standby Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Starting Standby Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

LX Series Heat Pump Unit Controller User’s Guide2

Ending Standby Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Slave Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

State Selection and Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Supervisory Control and Scheduling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Calculating the Space Temperature Setpoint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

The Effect of nviSetPoint on the Active Setpoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

The Effect of a Setpoint Offset on the Active Setpoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Humidity Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Defrost cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Cooling State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Mechanical Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Cooling Demand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Cooling Output Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Ending the Cooling State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Heating State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Heating Demand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Heating Output Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Cooling Outputs Used to Heat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Ending the Heating State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Night Purge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Morning Warm-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Fan Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Terminal Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Heating Terminal Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Cooling Terminal Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Networking Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Slave Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Load Shedding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Setting Up Network Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Network Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

LX Series Heat Pump Unit Controller User’s Guide 3

Optimum Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Requirements for Optimum Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Emergency Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Emergency Initiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Normal Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

The PID Loop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Proportional . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Integral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

How It Is Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Derivative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Dead Band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Alarm Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Alarm Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Alarm Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Alarm Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Heartbeat Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Disconnect Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Emergency Mode Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

User-Set Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Setting up the Heat Pump Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Persistent Network Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Setting Units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Input Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Heartbeat (Max Send Time). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Throttle (Min Send Time). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Delta Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64


Override Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Default Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Sensor Hardware Properties. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Input Signal Interpretation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Signal Type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Thermistor Type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Offset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Max Value, Min Value. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Reverse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Increment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

TransTable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Get Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Configuring an Input Represented as a LONMARK Object . . . . . . . . . . . . . . . . . . . . . . . 66

Output Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Output Signal Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Configuring an Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Creating a Functional Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Configuring an Output Represented as a Functional Block . . . . . . . . . . . . . . . . . . . . . . . . . 70

Heating-Cooling Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Fan-Valve Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

PID Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Alarm Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Space Temperatures and Humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Discharge Temperature and Auxiliary Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Fan Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Pump Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

General Settings Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Radiation Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Options Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Optimum Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79


Frost Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

Defrost Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

Humidity Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Network Input Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Heartbeat Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Network Output Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Object Manage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Object Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Communication Failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Electrical Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Out of Limits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Disabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

In Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

In Override . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Out of Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Network Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

nviApplicMode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

nviCoilDiffPress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

nviDischargeTemp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

nviEmergCmd. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

nviExtCmdOutputx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

nviFanSpeedCmd. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

nviFanState. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

nviHotWater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

nviOccCmd & nviOccManCmd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

nviOutdoorTemp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

nviPumpState . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

nviRefrigTemp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

nviSetPoint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

nviSetPtOffset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90


nviShedding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

nviSlave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

nviSpaceRH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

nviSpaceTemp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

nviWaterTemp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

nvoCtrlOutput. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

nvoDischargeSetPt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

nvoEffectSetPt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

nvoFanSpeed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

nvoHPalarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

nvoHPstate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

nvoHwInput . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

nvoOccState . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

nvoSpaceTemp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

nvoTerminalLoad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

nvoUnitStatus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

Standard Network Variable Types (SNVT). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

SNVT_hvac_emerg (103 HVAC Emergency Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

SNVT_hvac_mode (108) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

SNVT_hvac_status (112) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Alarm State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

SNVT_lev_percent (81) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

SNVT_occupancy (109) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

SNVT_switch (95). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Switch Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

SNVT_temp_p (105) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

SNVT_tod_event (128) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104



LX Series Heat Pump Unit ControllerUser's Guide

Introduction

Feature DescriptionThe LX Series Heat Pump Unit (HPU) Controller integrates into a LONWORKS® network for the control of almost any heat pump unit due to its wide range of output types and LONMARK® certification.

The LX Series Heat Pump Unit Controller controls the following equipment:

• four stages of mechanical heating or cooling

• modulating heating or cooling valves

• reversing valves

• floating valves for heating or cooling

• pump for geothermal application

• three fan speeds or variable speed fans

• humidifier and dehumidifier

The Heat Pump Unit Controller has five digital outputs supplying 1.0 ampere at 24 VAC. These outputs produce digital or Pulse Width Modulated (PWM) signals.

Also, two tri-mode analog outputs are on the circuit board. These outputs provide the following signals:

• linear signals over a 0 to 10 VDC range

• 10 VDC digital or PWM signals

• digital signal of 60 mA at 12 VDC

The Heat Pump Unit Controller has six inputs, each capable of one of 18 possible input types. Inputs have 12-bit resolution and are configured entirely by software.

For easy maintenance and installation, the controller is equipped with wizard connectors that can accept flat cable or wires. The controller uses a TP/FT 10; 78 kbps network configuration.

The information in this guide helps you to set up the Heat Pump Unit Controller, understand the operation of the device, and troubleshoot problems. Information is organized to follow the Heat Pump Unit Controller configuration wizard menu.

LX Series Heat Pump Unit Controller User's Guide 9

Sensor Configuration WizardThe Heat Pump Unit Controller incorporates the Johnson Controls® sensor configuration wizard. The wizard provides powerful and simple configuration tools for the hardware inputs. You can only select digital or analog inputs through the software. You do not need to move any circuit board jumpers.

Analog input signal types–resistive, voltage, current–are selected in software without hardware jumpers. Built-in conversion tables are provided for a large number of thermistors or other sensor types. You can easily create custom conversion tables by setting the offset, minimum, and maximum values in one dialog box for the input.

The sensor configuration wizard also provides direct access to network properties of the analog or digital input including the Standard Network Variable Type (SNVT), Heartbeat, Send on Delta, Override, Default Value, and Throttle settings. All of the input features are in one place; therefore, it is not necessary to switch back and forth between screens to fully configure an input.

The sensor configuration wizard provides warnings of configuration errors as they occur, allowing you to correct mistakes quickly.

The sensor configuration wizard is accessible in the LX-HPUL wizard view of an LX-HPUL device in FX Workbench. Each hardware input is represented by a separate LONMARK object. To configure each input, select the desired hardware input on the left side of the LX-HPUL wizard view and Sensor Configuration in the Wizard column of the view and click the Launch button. The sensor configuration wizard opens. Through use of the wizard, you can configure network inputs not directly controlled by the HPU Controller.

Control FeaturesThe Heat Pump Unit Controller provides Proportional plus Integral plus Derivative (PID) loops for advanced control of humidity, discharge temperature, and space temperature. Each PID loop has an individual, configurable dead band; and, provides gain and time adjustment for the integral and derivative terms, and gain adjustment for the proportional term.

Humidification and dehumidification sequences provide the Heat Pump Unit Controller with the ability to maintain space humidity at the desired level. Defrost cycles are started by the HPU when the differential pressure is high, or by a sequence in conjunction with the refrigerant temperature sensor. Space temperature control is done with a PI loop only, but the presence of the derivative term provides the HPU Controller with the ability to precisely adjust space temperature. Precision adjustment ensures both increased comfort and savings.

Often associated with air handlers, the HPU Controller provides advanced control settings including Optimum Start and load shedding.

LX Series Heat Pump Unit Controller User's Guide10

The Optimum Start function maintains statistics that enable the Heat Pump Unit Controller to predict the warm-up or cool-down time period needed to make the building ready for occupancy. The precise Optimum Start period is calculated every day using the current outdoor air temperature.

LONMARK Functional ProfileThe LX Series Heat Pump Unit Controller uses the LONWORKS protocol. The Heat Pump Unit Controller is LONMARK certified for interoperability on any LONWORKS network. The controller is set up through its own configuration wizard and through the Sensor configuration wizard. Use FX Workbench to install the device onto the network and bind the network variable connections.

Figure 1 shows the Heat Pump Unit Controller meets the LONMARK standard by providing the network variable inputs, network variable outputs, and configuration properties specified by the profile. In addition, the Heat Pump Unit Controller provides extra network variable inputs and outputs. These extra variables provide greater flexibility and a number of functions than required in the profile.

For example, functions determined by the network variables include slaving the controller to another unit through nviSlave or enabling the controller to act as the master node through nviUnitStatus.


Figure 1: LX Series Heat Pump Unit Controller:LONMARK Objects and Network Variables

LX- HPUL- 1 HeatPumpObject Type #8051

Configuration PropertiesOcc. Temperature Set Points (mandatory)

Maximum Send Time (mandatory)Minimum Send Time (optional)

nviSpaceTempSNVT_temp_p

MandatoryNetwork

Variables

OptionalNetworkVariables

ManufacturerNetwork

Variables

nviSetPointSNVT_temp_p

nvoFanSpeedSNVT_ switch

nvoTerminalLoadSNVT_lev_ percentnviFanSpeedCmd

SNVT_ switch

nvoDischargSetPtSNVT_temp_p

nviOccCmdSNVT_xx

nvoSpaceTempSNVT_temp_p

nviApplicModeSNVT_hvac_mode

nvoEffectSetPSNVT_temp_p

nviSetPtOffsetSNVT_temp_p

nvoOccStateSNVT_ occupancy

nviWaterTempSNVT_temp_p

nvoUnitStatusSNVT_hvac_status

nviDischargeTempSNVT_temp_p

nvoCtrlOutput1SNVT_ switch

nviRefrigTempSNVT_temp_p

nviSheddingSNVT_ switch

nviHotWaterSNVT_ switch

nviSlaveSNVT_lev_ percent

nviOutdoorTempSNVT_temp_p

nviOccManCmdSNVT_ occupancy

nvoCtrlOutput7SNVT_ switch

.

.

.

Manufacturer Configuration PropertiesPlease see the manual for details.

Wizard for configuration provided.

nviSpaceRHSNVT_lev_ percent

nviEmergCmdSNVT_hvac_ emer

nviFanStateSNVT_ switch

nviPumpStateSNVT_ switch

nviCoilDiffPressSNVT_press_p


The HPU Controller also has network inputs that permit the use of outside enthalpy sensors and space enthalpy sensors. These inputs provide better calculation of the cooling or heating effect of the outside air upon the conditioned space.

The input object has configurable conversion tables and hardware properties in the area marked Manufacturer Configuration Properties. Choose from a list of standard thermistors to select conversion properties and create your own custom tables. Hardware properties configuration allow you to modify your input from the software object. Figure 2 shows the output and input objects.

Figure 2: Output and Input Objects

LX-HPUL- 1 Hardware InputObject Type #1

nvoHwInputxSNVT_xxx

Offset (optional)Maximum Range (optional)Minimum Range (optional)

Minimum Send Delta (optional)Minimum Send Time (optional)Maximum Send Time (optional)

Override Value (optional)

Configuration Properties

MandatoryNetworkVariables

Object Major VersionObject Minor Version

Output Signal ConditioningPWM Period

Hardware PropertiesDefault Value

Manufacturer Configuration Properties

LX-HPUL- 1 Hardware OutputObject Type #3

nviExtCmdOutputxSNVT_ switch

Maximum Receive Time (optional)Override Value (optional)


MandatoryNetwork

Variables

Object Major VersionObject Minor Version

Output Signal ConditioningPWM Period

Hardware PropertiesDefault Value

Manufacturer Configuration Properties


The node object displays the nvoHPstate and nvoHPalarm variables as manufacturer’s variables. The node objects provide information about the alarm conditions in the Heat Pump Unit Controller and about the operating state of the device (Figure 3).

Units in LONWORKS NetworksNote: Use this section if you are using the Imperial System of measurement.

The Imperial System and the International System (SI) are the two main measurement systems used today. Table 1 compares Imperial units and SI units.Table 1: Comparing Imperial and SI UnitsImperial Units SIinch centimeter

yard meter

mile kilometer

degrees Fahrenheit degrees Centigrade/Celsius

Figure 3: Heat Pump Unit Controller Node

LX- HPUL-1 NodeObject Type #0

nvoStatusSNVT_obj_ status

Location (optional)Device Major Version (optional)Device Minor Version (optional)


nviRequestSNVT_obj_ request

Mandatory NetworkVariables

OptionalNetwork

Variables

ManufacturerNetwork

Variables

nvoFileDirectorySNVT_ address

nvoHPstateSNVT_state_64

nvoHPalarmSNVT_state_64

Manufacturer ConfigurationProperties

Maximum Send Time


The LONWORKS network and Echelon® SNVTs are based upon SI units. This basis creates some unavoidable problems in data conversion if you are using Imperial Units.

The LX-HPUL view in FX Workbench and other utilities provide some automatic conversion between SI and Imperial units. However, these are not ideal conversions because a whole number in one system becomes a long decimal fraction in the other. For example, 72°F is approximately equal to 22.22222°C.

The values created by converting Imperial to SI or SI to Imperial are subject to rounding errors. If you enter an Imperial value into a LONWORKS SNVT by using the HPU Controller configuration wizard, the value is converted, then rounded and written to the SNVT. When you want to monitor the SNVT, the value must be read from the SNVT, converted, and rounded again before it is displayed. Due to the two conversions and two rounding operations, the value may differ slightly from what you originally entered (Figure 4).

The same process and resulting rounding error applies to Standard Configuration Property Types (SCPTs).

Instructions for changing or modifying the units of measure used on your computer are provided in the Selecting a Measurement System or Selecting a Language section.

Language SelectionThe following may require you to change your language settings:

• You changed your regional settings by selecting a different region in the Regional and Language Options dialog box.

• You work on a site that is in a linguistic region other than your own.

Figure 4: Imperial Units in the LONWORKS Network

Value is written in Imperial Units.

Value is translated to SI units.

Value is rounded.

Value is read from SNVT.

Value is translated to SI units.

Value is rounded.

Data is displayed for monitoring in Imperial Units.

Units

Value is stored in SNVT.


• You are dissatisfied with the language displayed on program menus and dialog boxes.

You can change your language settings in the Advanced tab of the Regional and Language Options dialog box. Instructions are provided in the Selecting a Measurement System or Selecting a Language section.

Selecting a Measurement System or Selecting a Language To select units of measurement or to select a language:

1. In Microsoft® Windows XP® Operating System, click Start > Control Panel. The Control Panel appears.

2. In the Control Panel, open Date, Time, Language, and Regional Options.

3. Under the list titled Pick a Task, select and open the second item: Change the format of numbers, dates, and times (Figure 5).

Figure 5: Date, Time, Language and Regional Options Screen


4. Select your language region from the drop-down list. The number, time, and date formats fill automatically (Figure 6).

5. In the Number box, verify the number format uses a decimal point to indicate numerals representing values less than 1. For example, use 123,456,789.00, not 123 456 789,00. You must use a decimal point for the correct display of numerals.

6. In the Regional Options dialog box, click Customize.

Figure 6: Regional and Language Options


7. Click on the drop-down arrow next to the box labeled Measurement system, and select Metric (Figure 7).

8. Verify the Decimal symbol box contains a decimal point. If the Decimal symbol box does not contain a decimal point, select the symbol in the box and click Apply.

9. Click OK.

10. Click the Advanced tab and choose a language region by selecting from the drop-down list. Verify the correct language appears on program menus.

11. Click OK.

You have now set the units to appear in the LX-HPUL view in FX Workbench. If you select to have Imperial units appear, remember that the SNVTs still use SI units. If you are viewing the data in Imperial units, you are viewing a converted rounded value.

Figure 7: Customize Regional Options


Heat Pump Unit Controller Installation OverviewFigure 8 shows one possible installation of the Heat Pump Unit Controller. Inputs, outputs, heating, and cooling units have been marked.

Note: Not all possible sensors appear.

InputsThe Heat Pump Unit Controller has six universal inputs. You can use the HPU Controller Configuration wizard to configure universal inputs. There are two possible configurations for universal inputs:

• digital inputs or 10k ohm resistance inputs

• analog inputs sensing either current or voltage

Note: As the Heat Pump Unit Controller can connect to a maximum of six sensors, you may want to connect some sensors using the LONWORKS network. All valid network inputs have priority over hardware inputs.

10k Ohm or Digital InputThe universal input, when configured as a 10k ohm or digital input, accepts a 10k ohm resistance input or a digital input such as a switch (cold contact).

Figure 8: Possible HPU Installation

HeatingFilter Cooling

Humidifier

Intake Air

DATOATSe

tpoi

nt O

ffset

t

Tem

pera

ture

Hum

idity

Conditioned Space

Occ

upan

cy

LX-HPUL-1 Installation Overview

OAT Outside Air Temperature

DAT Discharge Air Temperature

Sensor Symbols

Humidity

Temperature

Digital Input

Heat Pump Enclosure

Win

dow

cont

act

3 Fan Speeds

Heat Pump Enclosure

DischargeAir


The 10k ohm resistance range accommodates 10k ohm thermistors used in space temperature sensors or duct temperature sensors, or 10k ohm potentiometers used as setpoint offsets.

Use the conversion table for resistance input of more than 10k ohm. The digital range accommodates the occupancy contact, bypass switch, and window switch.

See Figure 9 for wiring information regarding both digital and 10k ohm resistance inputs.

Figure 9: 10k Ohm or Digital Input

I1 I2 I3 I4 I6I5–+ + + + + +– –

ContactNO -NC

Thermistor10k Ohm

LX-HPUL-1

Both inputs are configured as 10k ohm or digital inputs. Configuration can be done in either the LX HPUL-1 wizard


Analog InputsAnalog inputs include current inputs with a range of 4 - 20 mA, and voltage inputs with a range of 0 - 10 VDC.

4 to 20 mA Analog Input, Externally Supplied

Current inputs require a power supply either on the sensor or wired in series with the sensor. To construct the current input, place a 500-ohm 0.25-watt resistor across the Heat Pump Unit Controller’s input terminals. See Figure 10 and Figure 11.

Sensors and SwitchesThe following sensors and switches can be connected to the Heat Pump Unit Controller.

Figure 10: Sensor Powered Analog Input

+–

Resistor:500 Ω − ¼

Watt

LX- HPUL-1

4 –

20 m

A

Sensor

180

I1 I2 I3 I4 I6I5–+ + + + + +– –

Internal 24 VDCpower supply

Ω= ohm

Controller source output 4 – 20 mA

Figure 11: Externally Powered Analog Input

–+

Resistor:500 Ω − ¼

Watt

LX- HPUL-1

4 –

20 m

A

–+

24VDC

Sensor

180

I1 I2 I3 I4 I6I5–+ + + + + +– –


Auxiliary Alarm Input This input is used to relay an alarm from an external device onto the building network.

Preferred SNVT types: SNVT_amp, SNVT_amp_ac, SNVT_amp_f, SNVT_lev_disc, SNVT_lev_percent, SNVT_switch, SNVT_temp_f, SNVT_temp_p.

Bypass Contact Input

A switch closure on the bypass contact input causes the Heat Pump Unit Controller to enter occupied mode for the period of time set as the bypass time. However, the Heat Pump Unit Controller must be in unoccupied or standby mode.

Preferred SNVT types: SNVT_lev_disc, SNVT_occupancy, SNVT_switch.

Coil Differential Pressure InputThe differential pressure is read on each side of the solenoid valve. On a high differential pressure, the Heat Pump Unit Controller starts the defrost cycle.

Preferred SNVT types: SNVT_press_f, SNVT_ press_p.

Coil Frost Contact InputIf the Heat Pump Unit Controller is in operation, a switch closure on the coil frost contact causes the Heat Pump to start a defrost cycle.

Preferred SNVT types: SNVT_lev_disc, SNVT_switch.

Discharge Temperature InputUse the discharge temperature input to maintain the discharge air temperature between the minimum and maximum discharge air temperature.

A linear equation between the minimum and maximum discharge air temperature and the space PID loops determines the discharge setpoint. During a high heating demand, the discharge setpoint moves to its maximum temperature. Conversely, during a high cooling demand, the discharge setpoint moves to its minimum temperature. The discharge temperature setpoint can be viewed from nvoDischargSetPt.

Preferred SNVT types: SNVT_temp, SNVT_temp_f, SNVT_temp_p.

Emergency Contact InputA switch closure on this input causes the HPU Controller to begin emergency operation.


Fan Speed Selector Input

Fan speed selector provides the Heat Pump Unit Controller with an ability to select up to three different fan speeds.



Fan State InputThe fan state input detects whether one of the three fan speeds is ON or OFF. If the fan state input does not correspond with one of the fan outputs for a period of time (known as alarm delay), then an alarm becomes active. If the fan state input is OFF, while one of the fan outputs is ON, then equipment requiring air circulation remains OFF or does not modulate.

Note: All outputs except for the fan disable when the fan state is OFF.

Preferred SNVT types: SNVT_amp, SNVT_amp_ac, SNVT_amp_f, SNVT_lev_disc, SNVT_lev_percent, SNVT_switch.

Mode SelectorMode Selector enables selection of different modes of operation by means of an analog signal, such as resistance, voltage, or current input.

Modes of operation available from this input are auto, heat, cool, fan only, and OFF. Table 2 describes the modes of operation.

Preferred SNVT types: SNVT_hvac_mode.

Occupancy InputA switch closure on this input sets the HPU Controller to occupied mode. The HPU Controller exits occupied mode when the switch is opened. Unless the controller is in bypass mode, the occupied contact does not function if the network variables nviOccCmd and nviOccManCmd are set to unoccupied.


Table 2: Modes of OperationMode of Operation DescriptionAuto Operates according to its setpoints and scheduled occupancy states.

The HPU controls heating, cooling, duct pressure, and the fresh air damper according to the setpoints and the configuration properties you enter. The controller switches between unoccupied, occupied, standby, and bypass modes according to its schedule and the occupancy and bypass contacts if these contacts are present.

Heat Operates according to the heating setpoints in heating mode only. The heating setpoint may change as the controller changes scheduled states. Cooling mode is unavailable. The fan is ON when heating is ON. The fan is OFF at other times unless configured as ON during occupied periods.

Cool Operates according to the cooling setpoints in cooling mode only. The cooling setpoints may change as the controller switches scheduled states. Heating mode is unavailable. The fan is ON when cooling is ON. The fan is OFF at other times unless configured as ON during occupied periods.

Fan Only Configures the fan ON during the scheduled occupied state. Heating and cooling is not available. Fan configuration is found on the Fan-Valve screen of the Heat Pump Unit Controller configuration wizard.

OFF Disables the control loop to OFF. All outputs are in the OFF state.


Outdoor Temperature InputThe outdoor temperature input depends upon the availability of the refrigerant temperature input to determine whether a defrost cycle is needed. It can also be used for the Optimum Start statistic.


Pump State Input

The pump state input detects if the pump is ON or OFF. If the pump state input is OFF, and the pump output is ON during an alarm delay, then an alarm becomes active. If the pump state input is OFF while the pump output is ON, cooling stages 1 - 4 (that require water or glycol circulation) remain OFF.

Note: This pump state only accepts a dry contact input.

Preferred SNVT types: SNVT_amp, SNVT_amp_ac, SNVT_amp_f, SNVT_lev_disc, SNVT_lev_percent, SNVT_switch.

Refrigerant Temperature Input

The refrigerant temperature sensor determines if the Heat Pump Unit Controller starts the defrost cycle. To perform this sequence, the controller also requires the outdoor air temperature.


Setpoint Offset InputSetpoint offset input provides a means of varying the setpoint during occupied and standby modes. The value from setpoint offset is added to the pair of active setpoints. See the Calculating the Space Temperature Setpoint section.

Preferred SNVT types: SNVT_temp, SNVT_temp_diff_p, SNVT_temp_f, SNVT_temp_p.

Space Humidity InputThe space humidity sensor provides the Heat Pump Unit Controller with the space relative humidity. Relative humidity can be used as an input to the humidity control PID loop.

Preferred SNVT types: SNVT_lev_percent.

Space Temperature InputThe Heat Pump Unit Controller uses the space temperature to control heating or cooling operations. One of the following inputs must be present for the HPU Controller to function:

• space temperature

• nviSlave


The space temperature sensor can be a 10k ohm thermistor, or it can provide a voltage or current input to the board.


Water Temperature InputThe Heat Pump Unit Controller provides heating or cooling through a single two-pipe system with a heating or cooling valve. If you use this system, the device must know the state (either hot or cold) of the available water. When you use the hardware water temperature input, the Heat Pump Unit Controller can decide if the water is sufficiently hot or cold for heating or cooling.

The network inputs nviHotWater and nviWaterTemp are available for receiving the water state or temperature, and have priority over the hardware input. If nviHotWater state and value are zero, the HPU Controller functions as if the water is cold. If nviHotWater state and value are unequal to zero, the HPU Controller functions as if the water is hot. If the water temperature is lower than the space temperature, water is considered cold; if the water temperature is higher than the space temperature, water is considered hot. The nviHotWater network input has priority over nviWaterTemp if both values are received.


Window Contact Input

If the Heat Pump Unit Controller is in occupied, bypass, or standby mode, and the heat pump is in operation (one of the fan speeds is ON), then a switch closure on the window contact input causes the HPU Controller to enter unoccupied mode. All outputs turn OFF until a demand from the unoccupied heating and cooling space temperature setpoints commands the unit into heating or cooling.

Preferred SNVT types: SNVT_lev_disc, SNVT_occupancy, SNVT_switch.Table 3: Sensor and Switch Preferred SNVT Type (Part 1 of 2)Sensor or Switch Preferred SNVT TypeAuxiliary Alarm Input SNVT_amp

SNVT_amp_acSNVT_amp_fSNVT_lev_disc

SNVT_lev_percentSNVT_switchSNVT_temp_fSNVT_temp_p

Bypass Contact Input SNVT_lev_discSNVT_lev_occupancy

SNVT_switch

Coil Differential Pressure Input SNVT_press_f SNVT_press_p

Coil Frost Contact Input SNVT_lev_disc SNVT_switch

Discharge Temperature Input SNVT_tempSNVT_temp_p

SNVT_temp_f

Emergency Contact Input SNVT_lev_discSNVT_lev_occupancy

SNVT_switch

Fan Speed Selector Input SNVT_lev_discSNVT_lev_occupancy

SNVT_switch

Fan State Input SNVT_ampSNVT_amp_acSNVT_amp_f

SNVT_lev_percentSNVT_switchSNVT_lev_disc

Mode Selector SNVT_hvac_mode


Occupancy Input SNVT_lev_discSNVT_lev_occupancy

SNVT_switch

Outdoor Temperature Input SNVT_tempSNVT_temp_p

SNVT_temp_f

Pump State Input SNVT_ampSNVT_amp_acSNVT_amp_f

SNVT_lev_discSNVT_lev_percentSNVT_switch

Refrigerant Temperature Input SNVT_tempSNVT_temp_f

SNVT_temp_p

Setpoint Offset Input SNVT_tempSNVT_temp_diff

SNVT_temp_fSNVT_temp_p

Space Humidity Input SNVT_lev_percent

Space Temperature Input SNVT_tempSNVT_temp_f

SNVT_temp_p

Water Temperature Input SNVT_tempSNVT_temp_f

SNVT_temp_p

Window Contact Input SNVT_lev_discSNVT_switch

SNVT_occupancy

Table 3: Sensor and Switch Preferred SNVT Type (Part 2 of 2)Sensor or Switch Preferred SNVT Type


OutputsYou can configure the Heat Pump Unit Controller analog outputs as analog, digital, or PWM outputs. If you configure the analog output as a digital output with the wizard, it supplies 60 mA at 12 VDC. This function is useful when driving relays external to the board. See Figure 12.

The characteristics of the analog outputs are described in Table 4.

Analog Output ProtectionAnalog Outputs are protected by an auto-reset fuse with a maximum current capacity defined by the following two points:

• 100 mA at 68°F (20°C)

• 0 mA at 140°F (60°C)

Digital OutputsThe digital outputs of the Heat Pump Unit Controller use triacs to switch the output signal. Each digital output is capable of conducting 1 ampere.

Digital outputs work as a switch to control the current (Figure 13). The current source is separate from the transformers supplying the current for the HPU Controller.

The HPU Controller uses a half-wave power supply. Any other half-wave power supply that connects with the controller through the outputs or inputs must be in phase with the power supply of the controller.

Table 4: Tri-Mode Analog Output CharacteristicsMode Maximum Current and Voltage Voltage RangeDigital 60 mA at 12 VDC (200 ohm load) 0 – 12 VDC

Analog 50 mA at 10 VDC 0 – 10 VDC (linear)

PWM 50 mA at 10 VDC 0 or 10 VDC180

DO1 C DO2 C DO3 C DO4 C DO5 C AO1 AO2–

K

Connect a diode tothe relay terminal.(Ir = 1A @ Vr=25V)

12Vdc RelayMax load 200 Ohms

Figure 12: Analog Output Driving an External Relay


Note: Do not share grounds between a full-wave and a half-wave power supply.

By using the heat pump configuration wizard, you can reverse any digital output scale. Normally ON is a 100% output. When the output is reversed, ON is a 0% output.

You can override any digital output to a previously set value using the HPU Controller object override command. The override values are set during the configuration process. The configuration wizard provides a screen for issuing object commands including the override command. See the Object Manage section for more information.

DO1 C DO2 C DO3 C DO4 C DO5 C AO1 AO2–

Power Supply24 VAC

LC

Maximum Current

1A at 24 VAC

Figure 13: Heat Pump Unit Controller Digital Outputs


Staged OutputsWhen there are multiple heating or cooling outputs, you can organize the outputs into stages that turn on sequentially one after the other. In the general sequence, heating or cooling stages (n) must be open for the period of time specified in the minimum heating period before heating or cooling stage (n+1) can turn on. For example, heating stage 1 must be open for the minimum heating period before duct heating stage 2 turns on. See Figure 14.

Output SelectionsThere are 31 possible output selections. Several output selections are dependent upon other output selections. For example, you can turn off cooling 1 - 4 depending on the setting of the reversing valve.

Fan Speed 1 - 3

Fan Speed outputs provide digital fan speed control. See the Fan Operation section for more information on fan speed operation.

Heating Outputs 1 - 4

Heating outputs 1 - 4 are staged outputs that turn ON after heating valve outputs are open 100%.

Cooling Outputs 1 - 4Cooling outputs 1 - 4 are staged outputs that turn ON after cooling valve outputs are open 100%.

Reversing Valve

The reversing valve has two states. If the reversing valve is defined and is ON, cooling outputs 1 - 3 act as heating outputs.

Time

Minimum heating period



Hea

ting

Effo

rt

Stage 1 ON Stage 1 ON

Stage 2 ON

Stage 1 ON

Stage 2 ON

Stage 3 ON

Heating commanded to 100% ON at this time.

Stage 2 turns ON.

Stage 3 turns ON.

100%

Stage 1 turns ON.

Figure 14: Staged Outputs


Humidifier and Dehumidifier OutputsBoth digital and analog humidifier and dehumidifier outputs are available. The fan must be ON to enable the humidifier and dehumidifier outputs.

The Heat Pump Unit Controller uses the assigned outputs to maintain the humidity at a level defined by the humidity setpoint on the general settings screen. There is a delay when switching between humidification and dehumidification. You can enter the time period for the delay on the general settings screen.

The Heat Pump Unit Controller also offers the possibility to dehumidify with the cooling coil. See the Humidity Control section for more information. Table 5 describes the assigned outputs.

Mode SelectionThe Heat Pump Unit Controller has several different modes of operation. Each mode has a unique group of setpoints. Modes initiate as a result of any of the following:

• change of value in nviOccCmd

• change of value in nviOccManCmd

• occupied button press

• bypass button press

• window open/close contact

While in any mode, the Heat Pump Unit Controller can enter a heating or cooling state as required to maintain the space within the limits of the setpoints. Setpoints for each mode are shown in Table 6.

Table 5: Assigned OutputsAssigned Output DescriptionHeat Valve ON-OFF Operates digital heating valve.

Cool Valve ON-OFF Operates digital cooling valve.

Heat Cool Valve ON-OFF Operates digital heating-cooling valve according to water temperature.

Heat Valve Open or Close Operates heating floating valves.

Cooling Valve Open or Close Operates cooling floating valves.

Heat Cool Valve Open or Close Operates heating-cooling floating valves according to the water temperature.

Fan Speed Modulate(FAN_SPEED_MOD)

Provides a variable speed fan control output.

Heating Modulate(HEATING_MOD)

Provides the modulated heating control output.

Heating or Cooling Valve Modulate(HEATING_VALVE_MOD)(COOLING_VALVE_MOD)

Provides modulated heating or cooling valve outputs.

Pump Provides digital pump control for applications like those involving a geothermal heat pump.


Network Variables Used for Mode SelectionTable 6 shows the values and modes for the nviOccCmd and the nviOccManCmd network variables.

The network variable nviOccCmd commands the Heat Pump Unit Controller to change modes according to the value of the variable. You can change the value of nviOccCmd by a schedule or other supervisory input.

Use the network variable nviOccManCmd to manually command the Heat Pump Unit Controller to change modes. Possible values of nviOccCmd and nviOccManCmd are shown in Table 6.

You can manually command the HPU to change modes through network variable nviOccManCmd. Because manual commands (commands entered by the operator) have priority over mode commands from a scheduler node, nviOccManCmd has priority over nviOccCmd. Both network variable inputs have priority over the occupancy contact or bypass button press. See Table 7.

If nviOccCmd and nviOccManCmd are set to OC_NUL, OC_BYPASS, or OC_STANDBY, and the occupancy contact is OFF or unassigned, then the Heat Pump Unit Controller is in unoccupied mode.

When the window contact is ON, the schedule is set to OC_UNOCCUPIED, and the fan and all other mechanical equipment cease operation. For example, if the window is opened, an unoccupied room remains unheated ensuring that heat and energy is not lost.

If nviOccCmd and nviOccManCmd are set to OC_NUL, OC_BYPASS, or OC_STANDBY, and the occupancy contact is ON, then the Heat Pump Unit Controller is in occupied mode.

Table 6: Values of nviOccCmd or nviOccManCmd and ModesIdentifier Heat Pump Unit Controller

ModeSetpoints

OC_OCCUPIED Occupied mode Occupied heat and cool

OC_UNOCCUPIED Unoccupied mode Unoccupied heat and cool

OC_BYPASS Bypass mode Occupied heat and cool

OC_STANDBY Standby mode Standby heat and cool

OC_NUL Invalid data Unoccupied heat and cool

Table 7: Priorities of Mode Changing InputsPriority Level1

1. Priority 1 is the highest.

Input Function

1 Window Contact Allows unoccupied mode.

2 nviOccManCmd manual mode change

3 nviOccCmd scheduled mode change

4 Occupancy contact enter occupied mode

5 Bypass button press enter bypass mode and start the bypass timer


When you press the bypass button in either unoccupied or standby mode, it causes the Heat Pump Unit Controller to enter bypass mode.

Occupied ModeOccupied mode makes the building environment comfortable for occupants.

Starting Occupied Mode

Occupied mode begins as result of one of the following events:

• A command is received on nviOccManCmd or nviOccCmd. You can modify the network variable nviOccCmd by the building schedule. You can also manually modify the network variable nviOccManCmd at a computer connected to the network.

• The occupancy switch is closed when both nviOccCmd and nviOccManCmd are set to OC_NUL, OC_BYPASS, or OC_STANDY.

Occupied mode uses the occupied setpoints that you set when configuring the controller wizard. During occupied mode, the Heat Pump Unit Controller uses outputs to heat or cool the space as required to maintain the temperature within the limits set by the occupied setpoints.

Ending Occupied Mode

The Heat Pump Unit Controller exits occupied mode when any one of the following events occurs:

• Another state is commanded through network variable nviOccManCmd. Use this method for a manual override from a computer.

• Another state is commanded through network variable nviOccCmd. Use this method with a scheduler node.

• The occupancy contact opens while nviOccCmd and nviOccManCmd are set to OCC_NUL, OC_BYPASS, or OC_STANDY.

• The window contact is closed, and the occupancy status moves to OC_UNOCCUPIED.

Unoccupied ModeThe Heat Pump Unit Controller uses Unoccupied mode when the building is empty. Unoccupied mode allows the space temperature a greater variance than in occupied mode. However, unoccupied mode keeps the building close enough to the occupied range of temperature that it can be made ready for occupation on a regular schedule.

Starting Unoccupied Mode

Unoccupied mode starts as a result of one of the following events:

• The unoccupied state is commanded by nviOccManCmd. Use this method for a manual override.


• A schedule change by a supervisory node sets the network variable nviOccCmd to OC_UNOCCUPIED. Because nviOccManCmd has priority over nviOccCmd, nviOccManCmd must be set to OC_NUL for the schedule change to occur.

• The occupancy contact is open or not assigned, and both nviOccManCmd and nviOccCmd are set to OC_NUL. Use this method to manually switch between occupied and unoccupied modes.

• The window contact is opened and the Heat Pump Unit Controller enters the currently scheduled mode, or the mode currently commanded by the occupancy contact.

Unoccupied mode cannot begin if the Heat Pump Unit Controller is currently in bypass mode. Unoccupied mode uses the unoccupied setpoints that you set in the configuration wizard.

During the unoccupied state, the controller heats or cools the space as required to maintain the temperature within the limits described by the unoccupied setpoints. In unoccupied mode, the setpoint offset, either from input or network variable, has no effect on the effective setpoint.

Ending Unoccupied Mode

Unoccupied mode ends when any one of the following situations occurs:

• Another mode is commanded by nviOccCmd whereas nviOccManCmd is set to OC-NUL. Use this method to implement a schedule.

• Another mode is commanded by nviOccManCmd. Use this method as a manual override.

• The bypass button on the space temperature sensor is pressed; this button short-circuits the sensor.

• The occupied contact is closed, and both nviOccCmd and nviOccManCmd are invalid.

• The bypass contact input is pressed.

• The window contact is closed and the occupancy status moves to OC_UNOCCUPIED.

Bypass ModeBypass mode uses the occupied setpoints to provide a comfortable environment when individuals are in a space outside of their usual scheduled time.

Bypass mode is temporary. The duration of bypass mode is a period of time called bypass time. Bypass time is set on the General Settings configuration screen.

When the HPU Controller enters bypass mode, the bypass time period begins. Conversely, when the bypass time period ends, the HPU Controller exits bypass mode.


Starting Bypass ModeYou can command the Heat Pump Unit Controller to enter bypass mode by either nviOccManCmd or by nviOccCmd. See the Network Variables Used for Mode Selection section for more information.

The Heat Pump Unit Controller enters bypass mode when any of the following events occur during unoccupied or standby mode:

• The bypass button on the space temperature sensor is pressed.

• The bypass contact is closed.

The Heat Pump Unit Controller does not enter bypass mode if the bypass time is set to zero.

Ending Bypass ModeThe Heat Pump Unit Controller exits bypass mode when any of the following events occur:

• an occupancy contact is closed; the HPU Controller enters occupied mode.

• The window contact is closed; the occupancy status moves to OC_UNOCCUPIED.

• the bypass timer expires; the HPU Controller enters the currently scheduled mode, or the mode currently commanded by the occupancy contact.

If bypass mode ends due to the expiration of bypass time and nviOccManCmd is set to OC_BYPASS, the controller sets nviOccManCmd to OC_NUL. This scenario returns occupancy control to a scheduler using network input nviOccCmd or to an occupancy contact. If nviOccManCmd were not set to OC_NUL, it would have priority over nviOccCmd and the occupancy contact.

Standby ModeIn standby mode, the space temperature is allowed a larger amount of variance than in occupied mode. However, the space is maintained at a temperature close enough to the occupied setpoints so that it is made ready for occupancy quickly. Standby is intended for areas such as meeting rooms that are intermittently occupied during the normal working day.

Starting Standby Mode

Standby mode setpoints are entered during the HPU Controller configuration. The HPU Controller enters standby mode as a result of either the following events:

• A scheduler node writes a command to nviOccCmd.

• An operator writes a command to nviOccCmd and/or nviOccManCmd.

You can override any nviOccCmd commands with nviOccManCmd. See Table 7 for more information.

Note: For nviOccCmd to be effective, nviOccManCmd must be set to OC_NUL.


Ending Standby ModeThe Heat Pump Unit Controller exits standby mode when any one of the following events occur:

• The bypass button on the temperature sensor is pressed, or the bypass contact input is ON; these events initiate bypass mode.

• The occupancy contact is closed; this initiates occupied mode.

• The network variable nviOccManCmd is set to another value by an operator or program.

• The network variable nviOccManCmd is set to another value while nviOccManCmd is set to OC_NUL; you can use this method to follow a schedule.

• The window contact is closed, and the occupancy status is set to OC_UNOCCUPIED.

Slave ModeSlave mode commands the HPU Controller to follow the heating or cooling demand of another heat pump. The controller enters slave mode when nviSlave (SNVT_hvac_status) is bound to the nvoUnitStatus of another unit.

State Selection and DescriptionThe controller enters occupied, unoccupied, standby, and bypass modes depending on the schedule and other inputs, such as the bypass contact switch. Within each mode, the controller enters additional states, including heat, cool, night purge, and morning warm-up.

Supervisory Control and SchedulingThe network variable nviApplicMode coordinates the Heat Pump Unit Controller with a supervisory control such as a schedule or a Human Machine Interface (HMI). Network variable nviApplicMode is an SNVT_hvac_mode and must be bound to another SNVT_hvac_mode output from the HMI, supervisory control, or air handler.

When this connection is complete, the HMI or supervisory control sets the Heat Pump Unit Controller to different states through nviApplicMode.

For more information about nviApplicMode, see Table 33.

Calculating the Space Temperature SetpointWhen nviApplicMode is set to HVAC Auto, the space temperature setpoint determines whether the unit enters a heating or cooling state. In the following section, space temperature setpoint calculations are addressed before state descriptions to ensure your understanding of how the state is selected.


When you configure the Heat Pump Unit Controller, you enter three pairs of setpoints for the four operating states. Because bypass mode uses the same setpoints as occupied mode, there are only three pairs. These setpoint pairs are classified as occupied, unoccupied, and standby, and are stored in SCPTSetPnts. SCPT is an acronym for Standard Configuration Property Type.

Depending on the current mode, the Heat Pump Unit Controller selects a pair of setpoints as the active setpoints. After the selection, the active setpoints are modified by the following variables:

• nviSetPoint

• nviSetpointOffset

• Setpoint Input

The Effect of nviSetPoint on the Active Setpoints

You can use the LX-HPUL wizard in FX Workbench to change any setpoints with the variable nviSetPoint. If nviSetPoint has a valid value and the mode is standby or occupied, then the two active setpoints are calculated as follows:

The value of Setpoint_move and Setpoint Offset is added to each member of the active setpoint pair. For the following example, the Setpoint Offset value is considered to be zero.

Example: If nviSetPoint is equal to 75ºF (23.9ºC) and the two setpoints are 72ºF (22.2ºC) and 68ºF (20ºC), then:

The two setpoints equal 77ºF (25ºC) and 73ºF (22.8°C).

Note: The network variable nviSetPoint is inactive in unoccupied mode.

The Effect of a Setpoint Offset on the Active Setpoints

The Setpoint offset value is added to the pair of currently active setpoints. For example, if the setpoints are 72°F (22.2°C) and 68°F (20°C) and the setpoint offset is 2F° (1.1C°), then the values of the setpoints with the offset are (72+2)°F (22.2+1.1)°C and (68+2)°F (20+1.1)°C.

The two possible sources of a setpoint offset are the network variable nviSetpointOffset or a hardware input. The nviSetpointOffset variable allows you to change the value of the setpoint offset.

( )Setpoint_ move = −

+nviSetPo

occupied cool occupied heatint

_ _2

OffsetSetpoint oveSetpoint_mointsActiveSetppointsActive_Set ++=

( )2

F6872F75oveSetpoint_m °+−°=

F5oveSetpoint_m °=


Hardware inputs are secondary to network variable nviSetpointOffset. For the hardware input to be active, the value of nviSetpointOffset must be invalid, and occupancy mode cannot be unoccupied. The invalid value for nviSetPointOffset is 621.806°F (327.670°C). Connect the input to a 10k ohm potentiometer in the conditioned space.

Humidity ControlThe heat pump maintains the humidity level at the humidity setpoint that you enter on the General Settings screen of the Heat Pump Unit Controller configuration wizard. The humidity setpoint is stored in UCPThumidityLevelSetpoint. Fan speed one, two, or three must be ON for humidity control to work.

Perform humidity control using a PID loop. Enter the PID loop parameters on the PID screen of the Heat Pump Unit Controller configuration wizard. For a description of PID loop control, see The PID Loop section.

The Heat Pump Unit Controller maintains the humidity level at the humidity setpoint in three ways:

• switching ON or OFF the HUMIDIFIER_ON_OFF or DEHUMIDIFIER_ON_OFF

• modulating the HUMIDIFER_MOD or DEHUMIDIFIER_MOD outputs

• controlling any cooling equipment outputs

When you select any cooling output, it unlocks the dehumidifying settings. To dehumidify with a cooling coil, you must enter a minimum cooling override value, and the fan speed override value. Take into consideration that dehumidification is more efficient if the air goes through the cooling coil slowly.

When you switch between humidification and dehumidification, the Heat Pump Unit Controller delays for a fixed time period of 45 minutes.

Note: The humidification and dehumidification outputs have a minimum ON/OFF time.

Defrost cycleUse the defrost cycle to melt the accumulated ice on the HPU Controller’s evaporator. Defrost cycles are necessary in heating mode when the outside air temperature is low, and there is a possibility of ice accumulation. Ice accumulation reduces the efficiency of the Heat Pump Unit Controller by reducing the heat exchange between the evaporator and the outside air.

The HPU Controller enables the defrost cycle if one of the following conditions is present:

• The refrigerant temperature is lower than the outside air temperature by a pre-defined temperature differential setpoint.

• The coil differential pressure is higher than the pre-defined differential pressure setpoint.


• The heat pump has been in operation for the Heat Pump Run Time Before Defrost in heating mode, and the refrigerant temperature and/or coil differential pressure is not available.

The Heat Pump Unit Controller disables the defrost cycle if the cycle has been ON for the Maximum Defrost Time.

If you configure more than one defrost feature, the Heat Pump Unit Controller enables the defrost feature according to the priority level listed in Table 8.

Cooling StateThe Heat Pump Unit Controller controls the following cooling types:

• digital cooling

• staged digital cooling

• cooling using heat pump

• floating valve cooling

• modulated valve cooling

The HPU Controller uses mechanical cooling. This type of cooling uses chiller units and cooling coils to remove heat from a building.

Mechanical Cooling

The Heat Pump Unit Controller turns the mechanical cooling outputs ON when all the following conditions occur:

• Fan speeds 1, 2, or 3 are ON or fan speed modulation is at the minimum speed.

• All heating outputs have been OFF for at least the amount of time defined by the Change Over Delay on the Heating Cooling-Configuration screen UCPTchngeOverDelay.

• nviApplicMode must be set to HVAC_AUTO or HVAC_COOL.

• The space temperature input data must be valid, or the Heat Pump Unit Controller must be slaved to another unit.

• The outdoor temperature must be greater than the Minimum Outdoor Temperature entered on the Heating-Cooling Configuration screen.

• There must be a cooling demand. A cooling demand occurs as a result of a comparison between the space temperature and the active cooling setpoint.

Table 8: Priorities of Defrost CyclePriority Level Defrost Enabled ON1 Outdoor and refrigerant differential temperature

2 Coil differential pressure

3 Coil frost contact closure

4 Run time before defrost


• If a floating cooling valve is used, one output must be COOL_VALVE_OPEN and another output must be COOL_VALVE_CLOSE.

• The water used for cooling operation must be cold for the following output configurations to work:

• heat_cool_valve_on_off

• heat_cool_valve_close

• heat_cool_valve_open

• heat_cool_valve_mod

The water is considered cold when the water temperature is lower than the room temperature or the nviHotWater input received value or state is zero.

Note: nviHotWater has priority over the water temperature either from the input sensor or nviWaterTemp.

Cooling DemandCooling demand results from any one of the following:

• the error between the active cooling setpoint and the space temperature

• nviSlave

Cooling Output SequenceDuring an increasing cooling demand, the first fan stage turns ON, which enables all mechanical cooling equipment. After this, fan speed two and three turn ON. During a decreasing cooling demand, fan and mechanical cooling equipment are disabled in reverse order. However, fan speed one can remain ON in occupied mode because of the Always On option. See the Cooling Terminal Load section for more information.

If a cooling valve output is configured, cooling outputs 1 - 3 turn ON only after valve outputs are 100% open.

Cooling outputs 1 - 3 are staged outputs. See the Staged Outputs section for more information.

Ending the Cooling State

Cooling outputs shut off when the bias reaches a negligible amount. However, outputs may not shut off when the space temperature reaches the setpoint if the PID loop control has accumulated bias during the cooling stage.

Heating StateThe Heat Pump Unit Controller controls the following heating types:

• digital heating

• staged digital heating

• heat pump heating


• floating valve heating

• modulated valve heating

The Heat Pump Unit Controller turns ON the heating outputs when the following conditions are present:

• Fan speeds 1, 2, or 3 are ON, or fan speed modulation is at the minimum speed.

• Options for Permit Valve radiation heating and/or Permit Local radiation heating are checked.

Unless you configure another input as a reversing valve, all cooling outputs must be OFF for the period of time defined as Change Over Delay on the Heating Cooling Configuration screen.

If you configure another input as a reversing valve, the first stage of cooling turns on at the same time as the reversing valve. See the Cooling Outputs Used to Heat section for more information.

Note: You can use cooling outputs to dehumidify. In this instance, you can enable both cooling and heating outputs at the same time. The option to disable dehumidification in heating mode was designed to avoid this situation by keeping the cooling outputs OFF for dehumidifying in heating mode.

• The network variable nviApplicMode must be set to HVAC_AUTO or HVAC_HEAT.

• The HPU Controller must be operating with the following conditions present:

• The space temperature is received. This temperature can also be received through a hardware input or through nviSpaceTemp.

• The HPU is slaved to another unit through nviSlave.

• There is a heating demand (see the Heating Demand section), or the discharge temperature is above the minimum during a cooling demand.

• If a floating heating valve is used, one output opens the heating valve and another output closes the valve.

The water source used for the heating coils must be hot for the following control outputs to work:

• HEAT_COOL_VALVE_ON_OFF

• HEAT_COOL_VALVE_OPEN

• HEAT_COOL_VALVE_CLOSE

• HEAT_COOL_VALVE_MOD

The water is considered hot when the water temperature is warmer then the room temperature, or nviHotWater receives a value and state different than zero.

Note: The nviHotWater variable has priority over the water temperature read either from the input sensor or nviWaterTemp.


Heating DemandA heating demand results from the following:

• the error between the active heating setpoint and space temperature

• nviSlave

If heating demand is taken from nviSlave, the HPU Controller is operating in slave mode and is receiving the heating demand from another unit.

Heating Output Sequence

Heating outputs 1 - 4 are staged outputs. Heating output 1 is the first heating stage in the stage sequence. See the Staged Outputs section for more information.

Heating outputs 1 - 4 and Heating_Mod do not turn ON until all heating valve outputs are at 100%.

Cooling Outputs Used to HeatUse cooling outputs 1 - 4 to heat if you configure another output as a reversing valve. The reversing valve turns ON at the same moment as the first stage of cooling.

If the cooling outputs are used to heat, heating outputs 1 - 4 and Heating_Mod do not turn on until the cooling outputs are at 100%.

Ending the Heating State

The heating state ends when there is no demand for heating, and the first heating stage (if any) has endured for more than the minimum heating period.

If the PID loop control has accumulated bias during the heating stage, heating outputs may not shut off when the space temperature reaches the setpoint. The output shuts off when the bias reaches zero.

Night PurgeNight Purge freshens the building air before occupation or cools down a building before morning occupation. The HPU Controller enters Night Purge if nviApplicMode is set to HVAC_NIGHT_PURGE. This mode results from a binding with a supervisory Heating, Ventilating, Air Conditioning (HVAC) device, an HMI, or a scheduling system.

Night Purge is a scheduled operation that does not use any setpoints. During Night Purge only the fan restarts. Heating and cooling outputs are OFF.

If frost protection is enabled, the heat turns ON if the temperature in the conditioned space reaches 42.8°F (6°C). The heat turns OFF again once the space temperature reaches 46.4°F (8°C).


Morning Warm-upThe Heat Pump Unit Controller enters Morning Warm-up when nviApplicMode has the value of HVAC_MRNG_WRMUP. The HVAC_MRNG_WRMUP value may be the result of binding nviApplicMode with a network variable from a supervisory network system, such as nvoTerminalLoad.

Morning Warm-up uses occupied setpoints, and ends when nviApplicMode commands another state.

Fan OperationThree fan speeds are available in the Heat Pump Unit Controller. Fan speeds are started according to heating or cooling demand, and according to the outputs configured in the Heat Pump Unit Controller configuration wizard. Normal operation sequence begins with the HPU Controller commanding the first fan speed to turn ON. After this, the controller starts or modulates all cooling and heating outputs to their maximum capacity according to their respective demands. Finally, all other fan speeds are started according to their respective demands.

If the fan option Always On in occupied mode is selected, and the occupancy status is OC_OCCUPIED or OC_BYPASS, the first fan speed is ON. Otherwise, the first fan speed starts according to a cooling or heating demand.

Fan speeds two and three are controlled with a cooling and heating demand. However, heating outputs and cooling outputs must be configured for those fan speeds to start.

Use fan speeds two and three to increase cool or hot air volume in the room. For example, during a heating demand, it is not acceptable to increase the air volume if the discharge air is not reheated; this situation creates discomfort for room occupants as they receive colder air.


The minimum time that any fan speed must be ON before it turns OFF, and the minimum time that any fan speed must be OFF before it turns ON, are both set in the Fan-Valve screen of the Heat Pump Unit Controller configuration wizard. Enter a value in the ON/OFF period box on that screen. See Figure 15.

Terminal LoadTerminal load describes the energy consumption of a HPU Controller for both heating and cooling operations. The network variable nvoTerminalLoad transmits the terminal load of a HPU Controller over the network.

Figure 15: Fan-Valve Screen of the Heat Pump Unit Controller Configuration Wizard


Heating Terminal LoadNegative terminal load values represent heating terminal loads. Heating effort increases as terminal load decreases. At 100% heating effort, the Terminal Load is -100% (Figure 16).

Term

inal

Loa

d

Time

Heating Effort

Heating Terminal Load0%

-50%

-100

%

0%10

0%50

%

Figure 16: Heating Terminal Load


Cooling Terminal LoadPositive terminal load values represent the cooling terminal loads. Terminal load increases as cooling effort increases. At 100% cooling effort, the Terminal Load is 100% (Figure 17).

Term

inal

Loa

d

Time

Cooling Effort

Cooling Terminal Load10

0%50

%0%

100%

0%50

%

Figure 17: Cooling Terminal Load


Networking OperationsThis section describes the operations that occur only as a result of network connections. Properties of network variables are also addressed.

Slave OperationThe HPU Controller follows the demands of another heat pump unit controller if nviSlave is bound to the nvoUnitStatus of the other controller.

The network variable nviSlave is type SNVT_hvac_status.

Load SheddingIf the Heat Pump Unit Controller receives an input on nviShedding, it reduces its output. As the value of nviShedding increases, the Heat Pump Unit Controller further reduces its output.

For example, if nviShedding is at 25%, heating and cooling outputs do not exceed 75%. Shedding stops if the frost protection is enabled, and the space temperature falls under 46°F (8°C).

The network variable nviShedding is a type SNVT_switch.

Setting up Network ConnectionsThe Heat Pump Unit Controller interfaces through the Local Operating Network (LON) to controllers using the LonTalk® protocol.

Whereas the Heat Pump Unit Controller can function without a network connection, the network variables sent and received over the LON by the Heat Pump Unit Controller can affect all of its operations.


Network OutputsThe network variables have the attributes Heartbeat, Send on Delta, and Throttle in common. These attributes are defined in Table 9. Table 10 defines the associated network inputs.Table 9: Network OutputsAttribute DescriptionHeartbeat Heartbeat is the maximum amount of time that must pass before the network

variable automatically transmits. The presence of the heartbeat attribute indicates that functions are proceeding normally. Failure to receive a signal at the other node within a heartbeat interval causes an alarm message to be sent over the network.Heartbeat is like a countdown timer. Every time that a message is sent, the Heartbeat timer resets to the full heartbeat value.Heartbeat signals are not always sent. If the monitored data changes more than is required by the Send on Delta setting within a shorter period of time than the heartbeat, the data is sent on the network, and the heartbeat message is not sent. Instead, the heartbeat timer is reset and counts down again.The heartbeat timer is reset every time that a message is transmitted. Only when the heartbeat timer reaches zero is the heartbeat message sent.Heartbeat provides a method of ensuring that points have not lost connection, and that the network is functioning. Whereas throttle restricts how often messages are sent, heartbeat ensures that messages are sent regularly. Heartbeat is disabled by setting it to zero.

Send on Delta Send on Delta causes a message to be sent when the monitored data changes by a previously set proportion. Send on Delta restricts extraneous network noise by transmitting only signals that indicate a meaningful amount of change.If the monitored data does not change for a period of time equal to the heartbeat interval, the data is sent as a heartbeat signal.

Throttle Throttle sets the minimum update period and acts as a limit on excessive network traffic. If the value of a point on the network is constantly fluctuating at a rapid rate and set to Send on Delta, the network can be flooded by data from that point. Throttle prevents the variable from transmitting more than once every minimum update period regardless of how many fluctuations have occurred during that period. For example, rapid motion of the damper could drastically increase network traffic. Damper oscillations could also cause network traffic problems if data were sent on every cycle of oscillation. Throttle can prevent network congestion in either of these cases by limiting the number of sends per time interval to a meaningful number. The larger the throttle number, the less frequently the network variable transmitted. Throttle units are in seconds. Throttle is disabled by setting it to zero.

Table 10: Network InputsAttribute DescriptionHeartbeat The maximum time period that the network variable waits for a message

before entering the heartbeat failure state determines the heartbeat effect on a network input. When a heartbeat failure state is entered, the value becomes invalid, and an alarm is sent.

Persistent When the network variable is marked as Persistent, the value is written to Electrically Erasable Programmable Read-Only Memory (EEPROM). Once written to EEPROM, the network variable value is preserved through power outages and resets. Every time a new network variable value is received, the new value is written into EEPROM.Because EEPROM can only accept a limited number of data writes, be careful how you use the persistent attribute. See the Persistent Network Variables section for more information.


Optimum StartOptimum Start prepares the space for occupancy in advance of the occupied period. If you start heating or cooling at the optimum time before the occupied period begins, the HPU Controller creates a comfortable space that is ready for occupancy without wasting energy. You can enable Optimum Start on the Options screen of the Heat Pump Unit Controller configuration wizard. Select the boxes labeled Enable Optimum Start for heating and Enable Optimum Start for cooling.

The HPU Controller maintains statistics that compare the outside temperature to the time required for the space to reach the occupied setpoints. These statistics are used to calculate the length of time required for Optimum Start.

Because the Optimum Start time is calculated every day for the current outside air temperature, it is much more energy efficient than simply starting the occupancy period before the actual arrival of occupants.

To configure Optimum Start, enter a value in the Maximum start time box to limit the Optimum Start time period. Optimum Start begins no sooner than the Maximum start time before the occupancy change. For example, if the space enters the occupied mode at 8:00 A.M. and the Maximum start time is 30 minutes, then Optimum Start does not begin before 7:30 A.M. Of course, Optimum Start can still begin at any time that is less than 30 minutes before 8:00 A.M.; for example, 7:41 A.M.

When statistics are not available, there are two options: The first option starts heating or cooling when the space occupancy changes. The second option allows Optimum Start to use the Maximum start time. To enable this feature, select the box labeled Use maximum time if no statistics on the Options configuration screen.

Regardless of which setting you choose, the first samples are saved when the HPU Controller does not have any statistics; these samples include the outside air temperature and the time required to reach the setpoint. Each day, Optimum Start uses the time recorded from the previous day’s sample. For example, if the Heat Pump Unit Controller recorded that the space reached the occupied setpoint in 25 minutes the first day, then on the second day the HPU Controller would begin Optimum Start 25 minutes before occupancy. If a maximum start time has been entered, the HPU Controller may use a value derived from the samples that is less than the maximum start time. However, the Heat Pump Unit Controller does not use a start time that is greater than the maximum start time value.

On the third day, the HPU Controller has two samples stored, and uses the two samples to calculate the Optimum Start time given the current outdoor temperature. From this point, all Optimum Starts are statistically calculated by the HPU Controller using its saved samples.

Requirements for Optimum StartRequirements for Optimum Start are as follows:

• The next state and time to the mode must be defined in advance.


• There must be a scheduler and the schedule must be properly bound to the Heat Pump Unit Controller using nviOccCmd.

• The network variable nviOccCmd must be set to SNVT type SNVT_tod_event. This is performed using the Changeable Nv Manager view of the LX-HPUL device in FX Workbench.

Since the Optimum Start is based on statistics resulting from the room temperature and the outside air temperature, you must configure the outdoor temperature as an input or receive it from the network through nviOutdoorTemp.

Emergency OperationEmergency Operation is for situations where the ventilation system should be shut down (for example, to combat the spread of a fire).

Emergency Operation stops any fans, pumps and heating or cooling action.

Emergency InitiationSetting nviEmergCmd to EMERG_SHUTDOWN and closing the emergency contact wired to the emergency input initiates emergency modes.

The network variable nviEmergCmd has priority over the emergency contact. The network variable nviEmergCmd is an SNVT_hvac_emerg (103). The invalid value is EMERG_NUL.

Normal Operation

When there is no emergency, and operations are normal, nviEmergCmd is set to EMERG_NORMAL.

The PID LoopPID loops provide precise control over space temperature and ventilation.

The control loop modulates its output to drive its input to a setpoint. Control loop inputs are the sensor readings of the temperature. Examples of these control loops include the fan speeds and the heating or cooling outputs.


The difference between the input and the setpoint is called the error. Controller output is a function of the error.

The Heat Pump Unit Controller provides PID control settings through its configuration wizard. The PID screen is shown in Figure 19.

Controller

SpaceSensor Output

Inpu

t

Out

put

Setpoint

Figure 18: PID Controller with Input, Setpoint, and Output

Figure 19: Heat Pump Unit Controller Configuration Wizard: PID Screen


For space temperature, discharge temperature, and humidity levels, there are settings for proportional, integral, and derivative gain. Each of these gains contributes to the final output as shown in Figure 20.

ProportionalProportional control provides an output that is proportional to the error. The error is multiplied by a number called the gain. The result is used to produce the output.

For example, if the room temperature is 69°F (20.6°C) and the setpoint is 72°F (22.2°), then the error is 3F° (1.7C°). If the gain is equal to 10% per F°, the output is 30% of the maximum output value.

IntegralThe integral component has a gain and time setting. These work together to remove errors that accumulate over time.

Gain

The integral gain is similar to the proportional gain. The error is multiplied by the value you entered as integral gain. If the gain is equal to 5% per °F and the error is 2F°, the integral output is 10% of the maximum possible output signal.

Time

The integral gain differs from the proportional gain because the output increases the longer that the error persists. This increase occurs because the product of the error multiplied by the integral gain is periodically added to the output. When you enter the time, you are entering the length of the time period over which the error is added.

Proportional Integral Derivative Total Output+ + =

Figure 20: Total Output Composed of P, I, and D Components


How It Is UsedImagine a building in a cold climate where the temperature of a certain space is never quite warm enough. A log of the temperature of this space would produce a graph such as Figure 21.

In Figure 21, the temperature never quite falls low enough to turn on the proportional heat.

However, with a Proportional Integral controller, the error would accumulate over time. Periodically, a portion of the error would be added back into the error. The error would accumulate and would finally be large enough to turn the heat ON. See Figure 22.

DerivativeDerivative control opposes sudden changes in the input value.

Whereas Integral control is able to correct errors that persist over time, derivative control can respond quickly to sudden changes.

Tem

pera

ture

Time

Setpoint

Heat is ON

Heat is OFF.

Space Temperature

8:00 8:30 9:0010:00

Figure 21: Never Quite Warm Enough:Using Only a P Controller

Tem

pera

ture

Time

Setpoint

Heat is ON

Heat is OFF.

Heat is ON.

8:00 8:30 9:0010:00

Error accumulates.

Space Temperature

Figure 22: Heating Using a PI Controller


A derivative of a function is the rate of change of the function. Therefore, in a graph of temperature versus time, the derivative is the rate of change of the temperature. In this case, rate of change means the change in temperature per unit time. For example, this rate could be degrees per minute.

As mentioned previously, derivative control opposes the rate of change. As an example scenario, consider a hospital lobby in the arctic. Because the lobby changes temperature often, it has its own local heaters that are controlled by a PID loop. Every time the hospital doors open, the temperature in the lobby decreases quickly. This sudden drop in temperature is a large rate of change. The large rate of change is opposed by the derivative control. The derivative control increases the output of the PID loop that increases the output of the heaters. As the lobby temperature comes closer to the setpoint, the derivative control output decreases and finally becomes zero when the lobby temperature reaches setpoint.

Derivative control usually responds to measured values rather than to the actual direct input. By doing so, the derivative control is prevented from creating large, short spikes in the controller output. These spikes are the derivative control’s response to a sudden increase or decrease in error due to setpoint changes.

Gain

The derivative gain is the amplification of the derivative output. This gain is measured as a percentage per unit of change, where units are degrees Centigrade or Fahrenheit. If a value of 50 is entered into the Gain box, then each unit of error causes a 50% increase in derivative control output.

TimeTime refers to the period between measurements of the input. If the time is set to 3 seconds, and the gain is 25%/F°, then the derivative output is 25% of the error for each degree of error and recalculates every 3 seconds.


Dead BandThe dead band is a range of input values surrounding the central setpoint. This range of values is close enough to the setpoint that their effect is unnoticeable. While the input lies within the dead band, deviations from the setpoint are not calculated as errors. For example, if the dead band is equal to 1/2 x to the setpoint, then the dead band extends from setpoint - 1/2 x to setpoint + 1/2 x. The maximum amount of deviation allowed is ± 1/2 x. See Figure 23.

Using dead bands reduces mechanical wear and tear on moving parts because the mechanical parts no longer oscillate to accommodate trivial errors.

Alarm OperationThe Alarms Configuration screen (shown in Figure 24) of the Heat Pump Unit Controller configuration wizard provides a number of user-set alarms. You can configure and enable the alarms to match the requirements of your current site. User-set alarms are available for the following control points:

• space air temperature

• discharge air temperature

• space humidity

• auxiliary alarm

• fan alarm

• pump alarm

Setpointx

0.5x

0.5xInput

As soon as the input exceeds the deadband, the PID loop will sense an error at its input. Whatever the PID outputs will do next, depends on the PID loop settings.

As long as input stays within the deadband, the error will be zero. As long as the error is zero, the PID loop will not change its output signal.

Deadband with Value of x

Mag

nitu

de

Time

Deadband Limits

Deadband Limits

Figure 23: Effect of Dead Band upon PID Loop Error


In addition to the preceding user-set alarms, other alarms are provided. These include:

• heart beat alarms for network inputs

• disconnect alarms for sensor points

• an emergency mode alarm

Figure 24: Alarms Configuration Screen


Alarm FeaturesAlarms have a number of features that enable you to automatically and carefully monitor critical system information. Many of these features are visible in Figure 25. Table 11 describes the Alarm Features.

Table 11: Alarm Features (Part 1 of 2)Feature DescriptionMonitored Variable Displays the network variable or control point that is monitored by the

alarm. For example, if you have an alarm that sends a message whenever a space temperature deviates too far from the setpoint, then the monitored variable is the space temperature.

Alarm State Enables when a monitored variable has a value that causes an alarm.

Alarm Offset Displays the amount that the monitored variable can deviate from the setpoint before entering the alarm state. See Figure 25. An offset causes the alarm to become active when the value of the monitored variable is greater than or less than the range of values equal to the setpoint ± the offset. Alarms that use an alarm offset are often called deviation alarms.

Alarm Delay Displays the period of time that the monitored variable must be in the alarm state before an alarm message is generated. See Figure 25 and Figure 26.

Space Temp C

°

Features of a Deviation Alarm

Setpoint2220

15

25

2.0

C°

2.0

C°

Monitored Variable

Upper limit of Offset

Lower limit of Offset

Monitored variable exceeds value of offset + setpoint at this time.

An alarm message is not sent as the monitored variable is in the alarm state for less time than the value of the alarm delay.

Monitored variable enters alarm state at this time.

Alarm message is sent here after the expiration of the alarm delay.

Time

Offset = 2C°Alarm Delay = 10 minutes

10.0 min

10.0 min

Figure 25: Space Temperature Alarm


A number of alarms respond to the timing of network variables. Some of these are called heartbeat alarms since they respond to the heartbeat value. The heartbeat is the maximum length of time that can occur between transmissions of a variable on the network. If this time is exceeded, an alarm sounds.

Use the network variables nvoHPalarm and nvoUnitStatus to transmit alarms.

Alarm TypesFour alarm types are used in the Heat Pump Unit Controller. Table 12 describes these alarm types.

Alarm ProcedureWhen an alarm condition occurs, the following changes take place:

• The appropriate bits of nvoStatus and nvoHPalarm are set.

• The in_alarm field of nvoUnitStatus is set to one.

• The network variable nvoUnitStatus transmits information about the heat pump object.

The following text sorts the alarms by type, describes the conditions that generate an alarm, and organizes associated bits of the nvoStatus and nvoHPalarm into a table. Alarm types are heartbeat alarms, disconnect alarms, status alarms, and user-set alarms.

Heartbeat AlarmsHeartbeat Alarm time values are set on the Network Input pages of the Heat Pump Unit Controller configuration wizard or by modifying SCPTmaxRcvTime.

Alarm Low Limit Displays a value that is less than the setpoint. When the monitored variable becomes equal to or less than the alarm low limit, an alarm message transmits over the network. Alarms that use a low limit are often called low limit alarms. See Figure 26.

Alarm High Limit Displays a value that is greater than the setpoint. When the monitored variable becomes equal to or more than the alarm high limit, an alarm message transmits over the network. Alarms using high limits are often called high limit alarms. See Figure 26.

Table 12: Alarm TypesAlarm Type DescriptionDigital Alarms Monitors the state of digital network variables or hardware inputs. Digital

alarms also indicate when digital network variables differ in state. For example, the fan output and the fan state should always be the same. If they differ, a digital alarm transmits a message on the network.

High Limit Alarms Reports when an analog network variable or hardware input is greater than a user-set value called a high limit.

Low Limit Alarms Reports when an analog network variable or hardware input is less than a user-set value called a low limit.

Deviation Alarms Reports when a monitored analog value deviates from its setpoint by more than a user-set value known as an alarm offset.

Table 11: Alarm Features (Part 2 of 2)Feature Description


The Bit # refers to the Bit Number of nvoHPalarm. The column programmatic name refers to the programmatic name of nvoHPalarm with the format type UNVT_rt_alarm that relays the status of the object. If a heartbeat alarm is ON, a communication failure alarm sounds. The Bit #13 of nvoStatus, programmatic name comm._failure, turns ON. Table 13 describes the Heartbeat Alarms.Table 13: Heartbeat AlarmsMonitored Point Monitored

VariableDelay Time Bit # Programmatic Name

Application Mode nviApplicMode SCPTmaxRcvTime 1 nviApplicModeHeartBeat

Coil Differential Pressure

nviCoilDiffPress SCPTmaxRcvTime 13 nviCoilDiffPressHeartBeat

Discharge Temperature nviDischarge Temp SCPTmaxRcvTime 6 nviDischargeTempHeartBeat

Fan State nviFanState SCPTmaxRcvTime 7 nviFanStateHeartBeat

Fan Speed Command nviFanSpeedCmd SCPTmaxRcvTime 14 nviFanSpeedCmdHeartBeat

Hardware Output Value nviExtCmdOutput(x) SCPTmaxRcvTime 16–22 nviExtCmdOutputxHeartBeat

Occupancy Command nviOccCmd SCPTmaxRcvTime 3 nviOccCmdHeartBeat

Outdoor Temperature nviOutdoorTemp SCPTmaxRcvTime 10 nviOutdoorTempHeartBeat

Pump State nviPumpState SCPTmaxRcvTime 15 nviPumpStateHeartBeat

Refrigerant Temperature

nviRefrigerantTemp SCPTmaxRcvTime 12 nviRefrigTempHeartBeat

Setpoint Offset nviSetPtOffset SCPTmaxRcvTime 2 nviSetPtOffsetHeartBeat

Shedding Command nviShedding SCPTmaxRcvTime 8 nviSheddingHeartBeat

Supply Tem

p C°

Features of an Alarm Using High and Low Limits

Setpoint2220

15

25

Monitored variable falls below lower limit.

An alarm message is not sent as the monitored variable is in the alarm state for less time than the value of the alarm delay.

Monitored variable enters alarm state at this time.

10.0 min

Alarm message is sent at this time after the expiration of the alarm delay.

Time

18

Monitored Variable

Lower Alarm Limit = 18°CUpper Alarm Limit = 24°CAlarm Delay = 10 minutes

10.0 min

Upper Alarm Limit

Lower Alarm Limit

Figure 26: Discharge Temperature Alarm


Disconnect AlarmsThe column heading Bit # refers to the Bit Number of nvoHPalarm. The column programmatic name refers to the programmatic name of nvoHPalarm with the format type UNVT_rt_alarm that relays the status of the object. If a heartbeat alarm is ON, an electrical fault alarm sounds. The Bit #11 of nvoStatus, programmatic name electrical_fault, turns ON. Table 14 describes the Disconnect Alarms.

Emergency Mode Alarms

Emergency Mode is described in the Emergency Operation section. Emergency Mode alarm begins when the emergency mode begins. The column programmatic name refers to the programmatic name of nvoHPalarm with the format type UNVT_rt_alarm that relays the status of the object.

User-Set AlarmsThe Bit # refers to the Bit Number of nvoHPalarm. The column programmatic name refers to the programmatic name of nvoHPalarm with the format type UNVT_rt_alarm that relays the status of the object. If a user-set alarm comes ON, an out-of-limits alarm sounds. The Bit #4 of nvoStatus, programmatic name out_of_limits, turns ON.

Slave Input nviSlave SCPTmaxRcvTime 9 nviSlaveHeartBeat

Space Humidity nviSpaceRH SCPTmaxRcvTime 11 nviSpaceRHHeartBeat

Space Temperature nviSpaceTemp SCPTmaxRcvTime 0 nviSpaceTempHeartBeat

Water Temperature nviWaterTemp SCPTmaxRcvTime 4 nviWaterTempHeartBeat

Water Temperature State (hot/cold)

nviHotWater SCPTmaxRcvTime 5 nviHotWaterHeartBeat

Table 14: Disconnect AlarmsSensor Time

Disconnected Bit # Programmatic Name

Space Temperature Sensor

30 seconds 32 SpaceTempSensorFault

Discharge Air Temperature Sensor

30 seconds 33 DischargeTempSensorFault

Outdoor Air Temperature Sensor

30 seconds 34 OutdoorTempSensor

Refrigerant Temperature Sensor

30 seconds 35 RefrigerantTempSensor

Water Temperature Sensor

30 seconds 36 WaterTempSensorFault

Setpoint Offset 30 seconds 37 SetpointOffsetElecFault

Table 15: Emergency Mode AlarmMonitored State Bit # Programmatic nameEmergency Mode 48 Emergency

Table 13: Heartbeat AlarmsMonitored Point Monitored

VariableDelay Time Bit # Programmatic Name


These settings can be entered on the Alarm screen of the Heat Pump Unit Controller configuration wizard. See Figure 24.

Setting up the Heat Pump ControllerThis section provides you with step-by-step instructions on how to set up the Heat Pump Unit Controller using the configuration wizard. This section includes definitions of the terms used in the configuration wizard and a short explanation of how to use each section of the wizard.

Each screen of the configuration wizard is introduced by a large graphic of that screen and discussed under its own heading. For example, Heating-Cooling Configuration.

Persistent Network VariablesWhen a network variable is marked as persistent, the network variable value is written to Electrically Erasable Programmable Read-Only Memory (EEPROM). Every time it receives a new network variable value, the new value is written into EEPROM. Once written to EEPROM, the network variable value is preserved through power outages and resets.

However, EEPROM only accepts a limited number of data writes. The number of writes that EEPROM accepts is large, but it is still limited. Therefore, if the network variable input is constantly changing, it could exhaust the ability of the EEPROM to store it in permanent memory.

However, if the value of the network variable is constant, and if it is received on the network input at a fixed time interval, this does not cause the EEPROM to write new data. The EEPROM only writes new data when the data value changes.

Table 16: Configuration Variables for User-Set AlarmsMonitored Point

Alarm Type

Setpoints Bit#

Programmatic Name

Location Setpoints/ Delta

Time DelayLocation

Space Temperature

Deviation active heatingsetpoint - offset

38 LowSpaceTemp UCPTspaceTempAlarmDelta Field

UCPTspaceTempAlarm Time Field

active coolingsetpoint + offset

39 HighSpaceTemp

Discharge Air Temperature

Low low limit setpoint 40 LowDischargeTemp UCPTsupplyTempAlarmLoLimit Field

UCPTsupplyTempAlarm Time Field

High high limit setpoint

41 HighDischargeTemp UCPTsupplyTempAlarmHiLimit Field

Space Humidity

Deviation setpoint - offset 42 LowSpaceRH UCPThumidityAlarm Delta Field

UCPThumidityAlarm Time Field

setpoint + offset 43 HighSpaceRH

Fan State Digital Fan input differs from state of fan output

44 FanStateMismatch UCPTFanCurrentThreshold

UCPTfanAlarmTime

Pump State Digital Fan input differs from state of fan output

45 PumpStateOff N/A UCPTpumpAlarmTime

Auxiliary Alarm Input

Low lower than low limit setpoint

46 AuxiliaryLowAlarm UCPTauxiliaryAlarmLoLimit field

UCPTauxiliaryAlarmtime field

High higher than high limit setpoint

47 AuxiliaryHighAlarm UCPTauxiliaryAlarmHiLimit field


For these reasons, network variables that change infrequently (such as nviSetPoint) are better candidates for persistence than others.

Setting UnitsMeasurement units are shown at the bottom of the Heat Pump Unit Controller configuration wizard menu. Select the measurement units before you perform any other tasks. When you change the measurement units, all unsaved information you have entered into the HPU Controller configuration wizard is lost.

If you are using Imperial units of measure (such as degrees Fahrenheit, inches of water, or Btu) please see the Units in LONWORKS Networks section.

Note: If you change your measurement system, all the SNVT format types also change. The measurement unit you select in the wizard, either SI or Imperial, affects the nvoHwInputx SNVT format type. Once you configure an input through the wizard and select an SNVT Type, the format type is written in the database and a change of the measurement system unit no longer affects that network variable.

Input ConfigurationWhen you configure inputs you set the signal type, signal interpretation, and the SNVT that transmits the information over the network.

Inputs are configured from the sensor configuration wizard. Launch the wizard from either the Heat Pump Unit Controller configuration wizard or the Hardware Input LONmARK object in the LX-HPUL Wizard view of the device.

Figure 27: Inputs Configuration Window


To configure an input:

1. The numbers in the Sensor Input column correspond to the input numbers of the LX-HPUL. Click the drop-down arrow next to the input number you wish to configure.

2. Select an input type. Table 17 gives a brief description of the possible selections.

Table 17: Sensor Input Usage OptionsInput Selection DescriptionUNUSED Input not used by Heat Pump

SPACE_TEMP Space temperature input

DISCHARGE_TEMP Discharge air temperature input

OUTDOOR_TEMP Outdoor air temperature input

REFRIGERANT_TEMP Refrigerant temperature input

WATER_TEMP Water temperature input

SETPOINT Setpoint input

SPACE_HUMIDITY Space humidity input

COIL_DIFF_PRESSURE Coil differential pressure input

AUXILIARY_ALARM Auxiliary alarm input

FAN_STATE Fan state input

FAN_SPEED_SELECTOR Fan speed selector input

MODE_SELECTOR HVAC mode selector input

PUMP_STATE Pump state input

OCC_CONTACT Occupancy contact input

BYPASS_CONTACT Bypass contact input

WINDOW_CONTACT Window contact input

COIL_FROST_CONTACT Coil frost contact input

EMERGENCY_CONTACT Emergency contact input


3. Click Configure. The Sensor Configuration dialog box appears.

4. Enter the configuration settings and click OK.

The sensor configuration properties determine the frequency of network variable propagation. Use the Delta Value and Throttle to adjust a node’s overall transmission rate to the available network bandwidth. The transmission rate is particularly important when the network variable value changes frequently (for example, a sensor reading).

Heartbeat (Max Send Time)The maximum time period between automatic transmissions of the network variable on the network (whether the value of the variable has changed or not). Set Heartbeat to 0 to disable the Heartbeat.

Heartbeat is also referred to as Maximum Send Time.

Throttle (Min Send Time)Throttle is the minimum time period that must pass between network variable updates on the network. If the value of the network variable changes by more than the configured Delta Value, an update is sent only after this time expires. Set Throttle to 0 to disable Throttle.

Throttle is also referred to as Minimum Send Time.

Figure 28: Sensor Configuration Dialog Box


Delta ValueIndicates the minimum value change required to update the associated network output variable.

Override ValueThe value the network variable adopts when the Sensor object is in the overridden state.

Default ValueThe value the network variable adopts when the Sensor object is in the disabled state, or the sensor reading is invalid.

Sensor Hardware PropertiesThe hardware configuration properties of a particular sensor input. Settings made here correspond to the characteristics of the sensor hardware connected to the input.

Input Signal InterpretationDetermines how the input reading is converted into units of measurement (for example, degrees Celsius). See Table 18. Signal Interpretation Type selections might be limited if a Heating, Ventilating, and Air Conditioning (HVAC) object (for example, a heat pump object) uses a particular sensor input implemented on the same node.

The configuration property entry fields change depending on the selected Signal Interpretation Type.

Signal TypeDetermines the input signal type of the connected sensor. The following signal types are supported:

RESISTANCE - Resistive of Contact input

VOLTAGE_0_10V - 0 to 10 Volt input

MILLIAMPS_4_20MA - 4 to 20 milliamp input

Table 18: Input Signal Interpretation TypesInput Signal Interpretation Type

Description

DISCONNECTED Input not used by Heat Pump

LINEAR Linear Interpolation

TRANS_TABLE Translation Table

DIGITAL 2-state input (ON/OFF)

MULTI-LEVEL Multi-level input uses signal increment

STD_THERMISTOR Predefined translation table

SETPOINT_OFFSET Linear Interpolation with deadband


Thermistor TypeIf the associated input is a thermistor (THR) type, use this field to select the predefined translation table for linear interpolation of input values.

OffsetThe sensor-specific zero offset in measurement units. This value is added after translation/conversion of the raw signal.

Max Value, Min ValueDepending on the Input Signal Interpretation type, this settings has a different meaning. For LINEAR and SETPOINT_OFFSET types, they determine the range of the sensor in measurement units mapped to the predefined span of the hardware input signal (10 V, 16 mA, and so on). Linear interpolation calculates the sensor value.

For all other non-discrete Input Signal Interpretation Types, these settings define the upper and lower limit of the sensor object's output value.

ReverseUse this check box to reverse the object's output value. This setting applies to discrete inputs (ON/OFF) only.

Increment Defines the increase of input signal necessary to increment the output value (for example, network variable) by one, starting from zero.

For example: If the increment setting is 2 V, the network variable value is 3 at 6 V.

TransTableOpens a small window providing a table of 16 signal/value pairs to define a translation table for conversion of raw measured data into units of measurement. Input values are in kilo-ohm, V, or mA, with respect to the Input Signal Type chosen. Output values are in units according to the object’s selected output network variable type. Only values within the sensor range defined by Max Value and Min Value are considered.

Table 19: Thermistor TypesThermistor Type DescriptionDEFAULT_TYPE ACI/10 K-CP

TYPE_2 ACI/10 K-CP

TYPE_3 ACI/10 K-AN

TYPE_7 Greystone 10 K, Type 7

TYPE_12 Mamac Systems 10K, Type 12

TYPE_24 Greystone 10K, Type 24


Get ValueThis button is active when the associated device is configured, online, and connected. Once all hardware properties are set appropriately, click this button to retrieve the current sensor value form the network.

Configuring an Input Represented as a LONMARK ObjectTo configure an input represented as a LONMARK object:

1. Select the Hardware Input LONMARK object on the left side of the LX-HPUL Wizard view.

2. Select the Sensor Configuration wizard on the right side of the view.

3. Click the Launch button.

4. Click the Configure button.

5. In the Sensor Configuration dialog box, make the required selections.

Output ConfigurationWhen you configure outputs you define the function, output override value and output signal type.

Configure outputs through the Hardware Output wizard and launch them from the HPU Controller configuration wizard Object Outputs Configuration screen (Figure 29).


Table 20 describes all possible outputs that you can select from the Object Outputs Configuration screen.

Launch the Output wizard from either the Heat Pump Unit Controller configuration wizard.

Use the Hardware output to control any equipment that is not related to the Heat Pump Unit Controller. To do so, configure the output with the Actuator wizard launched from the object outputs configuration. In the Johnson Controls® Heat Pump Configuration wizard, leave the corresponding output UNASSIGNED. To control that output, use the nviExtCmdOutputx. Table 20: Output Selection and Description (Part 1 of 2)Selection Output DescriptionFAN_SPEED_1 Fan control output, speed 1

FAN_SPEED_2 Fan control output, speed 2

FAN_SPEED_3 Fan control output, speed 3

LOCAL_HEATING_1 Heating control output, stage 1




LOCAL_COOLING_1 Cooling and heat pump heating control output, stage 1




Figure 29: Object Outputs Configuration Screen


Output Signal TypesAvailable output types depend on which output signals you select. Three output types are available:

• Digital: A signal which has only two discrete states–ON or OFF

• PWM: A pulsed signal, where the time duration of the pulse (called the duty cycle) varies proportionally to the value transmitted. For example, a large duty cycle is translated as a larger value.

• Analog: A signal that is continuous over its entire range from 0 to 10 volts.

Configuring an OutputTo select and configure an output:

1. On the Output screen, numbers in the column Control Output correspond to the output numbers. Click the drop-down arrow next to the control output number that you want to configure.

2. Select an output type. See Table 20 for a brief definition of the possible selections.

3. If you want to assign an override value, select the Permit Override check box and then enter an override value as a percentage of the total output value. If you have chosen a digital output such as FAN_ON_OFF, then the override box changes to provide you with the option of ON or OFF for your override.

REVERSING_VALVE Two-state (opened or closed) reversing valve output

HUMIDIFIER_ON_OFF Humidifier control output

DEHUMIDIFIER_ON_OFF Dehumidifier control output

PUMP Pump control output

HEAT_VALVE_OPEN Heating floating valve output, open command

HEAT_VALVE_CLOSE Heating floating valve output, close command

COOL_VALVE_OPEN Cooling floating valve output, open command

COOL_VALVE_CLOSE Cooling floating valve output, close command

HEAT_COOL_VALVE_OPEN Heating/cooling floating valve output, open command

HEAT_COOL_VALVE_CLOSE Heating/cooling floating valve output, close command

FAN_SPEED_MOD Fan control output, variable speed

HEATING_MOD Modulated heating control output

HEATING_VALVE_MOD Modulated heating valve output

COOLING_VALVE_MOD Modulated cooling valve output

HEAT_COOL_VALVE_MOD Modulated heating/cooling valve output

HUMIDIFIER_MOD Modulated humidifier control output

DEHUMIDIFIER_MOD Modulated dehumidifier control output

Table 20: Output Selection and Description (Part 2 of 2)Selection Output Description


Note: Outputs are overridden by use of the Heat Pump Unit Controller LONMARK Object command. This command is available from the Object Manage screen of the Heat Pump Unit Controller configuration wizard.

4. Click Override ON to enable the override and Override OFF to disable it.

5. Select the Use Local Hardware check box if the output is connected to a physical actuator such as a motor, dehumidifier, or damper.

6. Click Configure.

7. In the Output Type box, click the drop-down arrow and select the output signal appropriate for your application. The output signal selection presented to you is dependent upon the choice you made in Step 2. See the Output Signal Types section for more information.

Note: Reverse Output - Normally, an output is ON when the output components are supplying 100% of the rated voltage. If you want the output to supply 0% of the rated voltage when ON, select the Reverse check box. For a digital output, the output is normally ON when the contacts are closed. When you reverse a digital output, the output is ON when the contacts are open.

You have now configured an output.

The architecture of the Heat Pump Unit Controller configuration wizard allows you to place functional blocks for your outputs on your network graphic. This ability increases the amount of network information that appears on the diagram and makes it easier to connect and display network variables.

Figure 30: Hardware Output1


Creating a Functional BlockTo create a functional block:

1. Place a Heat Pump Unit Controller device on the network diagram.

2. In the network diagram, select the Heat Pump Unit Controller device. Click and drag a functional block from the template onto the FX Workbench diagram. The Functional Block wizard opens.

3. Verify that the Heat Pump Unit Controller appears in the box labeled Device.

4. Select an output type.

5. Click OK.

6. Name the functional block.

7. Click OK.

You have now created and placed a functional block.

Configuring an Output Represented as a Functional Block

To configure an output represented as a functional block:

1. Select the Hardware Output in the LX-HPUL view in FX Workbench. Click the Launch button. The Actuator configuration wizard opens (Figure 31).

Figure 31: Hardware Output Configuration


2. In the Output Type box, select the type of output signal. See the Output Signal Types section for more information.

Note: Reverse Output - Normally, an output is ON when the output components are supplying 100% of the rated current and voltage. For a digital output, the ON state occurs when the contacts are closed. If you want the output when ON to supply 0% of the rated current and voltage or for the digital contacts to be open, then select the Reverse check box.

3. Assign an override value by entering an override value as a percentage of the total output.

Note: Normally, digital outputs are closed at 100% and open at 0%. See preceding Reverse Output text. Outputs are overridden by use of the actuator LONMARK Object command. This command is available from the Object screen of the actuator wizard.

4. Enter a default value in the Default Value box.

The default values are used when the Heat Pump Unit Controller is in the default state. The HPU Controller may enter the default state at startup. The state that the HPU Controller enters at startup is selected during commissioning.

Heating-Cooling ConfigurationOn the heating-cooling configuration screen (Figure 32), you define the following:

• occupied, standby, and unoccupied setpoints in both heating and cooling mode

• maximum and minimum discharge temperatures

• the change over delay (See A in Figure 32)

• mechanical cooling minimum operating times (See B in Figure 32)

Figure 32: Heating-Cooling Configuration Screen


Table 21: Heating-Cooling Configuration ParametersField DescriptionHeatingOccupied/Bypass Displays the heating setpoint for the occupied and bypass states.

Standby Displays the heating setpoint for the standby state.

Unoccupied Displays the heating setpoint for the unoccupied state.

Maximum DischargeTemperature

Displays the highest discharge air temperature you allow during the heating state.

Minimum HeatingTime

Displays the length of time that the duct and perimeter heating must stay ON once it has turned ON, and the length of time that the heating must stay OFF once it has turned OFF. Minimum heating time affects duct heating, perimeter heating, and staged outputs. Once a staged output has changed state, the next staged output cannot change state until the minimum heating time has passed.Note: Minimum Heating Time does not apply to modulated heating.

Turn ON Heat Stage 1 before using Modulated Heating

Use this option when you have a gas-heating system that needs to have its contact energized before modulating the gas-heating valve.

CoolingOccupied/Bypass Displays the cooling setpoint for the occupied and bypass states.

Standby Displays the cooling setpoint for the standby state.

Unoccupied Displays the cooling setpoint for the unoccupied state.

Minimum DischargeTemperature

Displays the minimum temperature of the discharge air that you allow during the cooling state.

Minimum Time ON Displays the minimum ON time for both heating and mechanical cooling.

Minimum Time OFF Displays the minimum OFF time for mechanical heating and cooling.

MechanicalMinimum Time ON Displays the minimum ON time for both heating and mechanical cooling.

Minimum Time OFF Displays the minimum OFF time for mechanical heating and cooling.

Minimum Outdoor Temperature

Displays the minimum outdoor air temperature at which mechanical cooling is allowed. Mechanical cooling disables when the outdoor air temperature is less than this value.

Heat/Cool Change OverDelay Displays the time interval that must pass before heating can occur after

cooling or cooling can occur after heating.


Fan-Valve ConfigurationOn this screen, you select the type of fan input, fan operation, and floating valve operating properties (Figure 33). See Table 22 for Fan-Valve Configuration Parameters.

Table 22: Fan-Valve Configuration Parameters (Part 1 of 2)Field DescriptionFanFan Speed Allows your sensor to measure the fan speed.

Fan Current Allows your sensor to measure the current drawn by the fan.

Current Threshold Sets the current at which you consider the fan to be ON. This affects the alarm that compares the states of the fan input and fan output.

Minimum Speed Displays the fan minimum speed.

ON/OFF Period Displays the period of time that must pass before the fan can turn ON after turning OFF; or the fan can turn OFF after turning ON.

Always ON in Occupied Mode Forces the fan to run continuously during occupied mode. If this box is not checked, the fan runs only when there is a heating or cooling demand.

Digital ValvesMinimum ON/OFF Period Displays the period of time that must pass before the fan can

turn ON after turning OFF, or the fan can turn OFF after turning ON.

Figure 33: Fan-Valve Configuration Screen


PID ConfigurationThe Heat Pump Unit Controller uses PID Loops to control the space temperature, discharge temperature, and humidity (Figure 34).

ValvesMinimum Position Displays the valves minimum position when there is a heating

or cooling demand. The valves are fully closed when there is no heating or cooling demand.

Drive Time for Floating Valves

Displays the period of time required for the valve to move from the fully closed to the fully open position.

Table 22: Fan-Valve Configuration Parameters (Part 2 of 2)Field Description

Figure 34: The PID Configuration Screen


Table 23 applies to the space temperature, discharge temperature, and humidity loops.

Alarm ConfigurationUsing this window, you can set the alarm high limits, low limits, offset, and alarm delays (Figure 35). See Table 24 for Alarm Configuration Parameters.

Table 23: PID Configuration ParametersField DescriptionProportional Gain Displays the gain per unit of the error.

Integral Gain Displays the gain per unit of the error.

Integral Time Displays the error repetitively sampled, and the integral gain is added to the output. The period of time between samples is the integral time. Enter the integral time for your process.

Derivative Gain Displays the gain per unit of the error.

Derivative Time Displays the derivative time–the time between two samples of the error. The two samples are compared to find the change in the error.

Dead Band Displays a number to define the size of the dead band. The dead band is a range of values symmetrical about the setpoint. See the Dead Band section for more information.

Use Discharge Air Temperature Only for Limitation

Allows the Heat Pump Unit Controller to control the unit with the room demand, and limits the discharge temperature between the minimum and maximum discharge temperature.If this option is unchecked, the Heat Pump Unit Controller tries to maintain the calculated discharge temperature setpoint. The discharge setpoint is calculated with a linear equation between the minimum and maximum discharge air temperature and the space PID loops.

Figure 35: Alarm Configuration Screen


Alarms monitor network variables or control points. These variables or points are called monitored variables. When a monitored variable has a value that causes an alarm message to be transmitted, then the monitored variable is in the alarm state.

Space Temperatures and Humidity

The Space Temperature and Humidity alarms have an alarm delay and an alarm offset only. For the alarm to become active, the monitored temperature must be outside of the range bounded by the setpoint plus ± alarm offset. However, this condition must exist for a length of time greater than the alarm delay to activate the alarm.

Discharge Temperature and Auxiliary Alarm

Both the Discharge Temperature and Auxiliary alarms have an alarm delay, high, and low limit. In this case, the alarm becomes active when the monitored input is outside of the range marked by the high and low limits. This condition must occur for a length of time greater than the alarm delay to activate the alarm.

Fan Alarm

The Fan Alarm applies to the fan state only. The fan alarm becomes active when one of following conditions exists for a time period greater than the alarm delay:

• The fan command is ON, and the fan input differs from the fan output, or the fan current is lower than the fan current threshold, or

• The fan command is OFF, and the fan input differs from the fan output, or the fan current is higher than the fan current threshold.

Whether a digital fan is ON or OFF, a decision is made by monitoring the fan speed or fan current. The alarm delay must be long enough to allow the fan to reach the ON or OFF stage. The fan speed or fan current level is set in the Fan-Valve Configuration screen.

Similarly, a variable speed fan requires time to speed up or slow down so that its speed matches the output. The alarm delay must be long enough to allow the fan to reach its commanded speed; otherwise, false alarms are generated.

Table 24: Alarm Configuration ParametersField DescriptionAlarm Delay Displays the length of time that an input must be in the alarm state before an

alarm sounds.

Alarm Offset Displays the amount of deviation from the setpoint that causes an alarm to sound.

Alarm Low Limit

Displays a value less than when the alarm becomes active. The alarm becomes active when the monitored variable falls below this value.

Alarm High Limit

Displays a value greater than which the alarm becomes active. The alarm becomes active when the monitored variable rises above this value.


Pump AlarmThe Pump alarm only applies to the pump state. The pump alarm is activated when the pump input differs from the pump output for a time period longer than the alarm delay.

General Settings ConfigurationFigure 36 shows the General Settings Configuration screen.

Figure 36: General Settings Configuration Screen


Radiation HeatingRadiation heating provides the option of starting heating outputs without starting the heat pump fan. Hot air mixes with the air in the space by natural convection. When you are not using the heating outputs, the option text appears in gray. Table 25 describes Radiation Heating.

Options ConfigurationOn the Options Configuration screen (Figure 37) you configure the following:

• Optimum Start

• Humidity Control

• Defrost Cycle

Table 25: Radiation Heat ParametersField DescriptionPermit ValveRadiation Heating

If selected, this enables the valve heating outputs to start on a heating demand before the fan starts. If this option is cleared, the valve heating outputs remain OFF if the fan is not ON.

Permit LocalRadiation Heating

If selected, this enables the local heating outputs to start on a heating demand before the fan starts. If this option is cleared, the local heating outputs remain OFF if the fan is not ON.

Heat Order During Unoccupied Mode

This enables you to select your unoccupied heating order: Radiation First, Ventilation Only.If you select Radiation First, the valve and/or heating outputs start first on a heating demand. If the option Ventilation Only is selected, the fan must be ON to start any heating outputs.


• Frost Protection

Optimum StartOptimum Start prepares the space for occupancy in advance of the occupied period. The HPU Controller uses stored daily statistics to calculate the length of time required each day to reach the occupied setpoints just as actual occupancy begins.

Optimum Start is described in the Optimum Start section.

Note: For Optimum Start to work, the network variable nviOccCmd must be set to SNVT type SNVT_tod_event. This procedure is done on the Network Inputs screen. See Change Type in Table 29 entitled Network Input Parameters for more information.

Figure 37: Options Configuration Screen


Frost ProtectionSelect the Frost Protection box to have the heat turned ON at a space temperature of 43°F (6°C) and turned off at 46°F (8°C). The heat turns ON independently of the temperature control. For example, the heat turns ON when nviApplicMode is set to HVAC_OFF.

The heat turns ON in the order determined by the heating order.

Defrost CycleDefrost cycle is necessary to remove the accumulated ice on the evaporator of the Heat Pump Unit Controller. Table 27 describes defrost cycle fields.

Table 26: Options ConfigurationField DescriptionMaximum Start Time Sets the maximum length of time before the start of occupancy

mode so that the Heat Pump Unit Controller can start to heat or cool the space.

Enable Optimum Start for Heating

Allows the Heat Pump Unit Controller to heat the space so that the space temperature is within the occupied setpoints when the occupied period begins.

Enable Optimum Start for Cooling

Allows the Heat Pump Unit Controller to cool the space so that the space temperature is within the occupied setpoints when the occupied period begins.

Use Maximum Start Time if No Statistics

Allows the Heat Pump Unit Controller to use the maximum start time as the length of time needed to heat or cool the space before occupancy. Once Optimum Start statistics have been recorded, the HPU Controller uses Optimum Start time periods calculated from the statistics. The Maximum Start Time is only used to limit the length of the Optimum Start Time.Bit 58 of the UCPTobject Options when set enables this option.If this box is not selected, the Heat Pump Unit Controller begins to heat or cool the space at the beginning of the occupied period. After the first start, it heats or cools the space at the recorded Optimum Start time. After the second start, it heats or cools the space at the calculated Optimum Start time.

Table 27: Defrost CycleField DescriptionStart On Refrigerant/Outdoor Differential Temperature

Displays a differential temperature that enables the defrost cycle.To use this option, you must have both refrigerant and outdoor air temperature configured as inputs or have them received through a network variable.

Start On Coil Differential Pressure

Displays a coil differential pressure that enables the defrost cycle.

Heat Pump Run Time Before Defrost

Displays a value for the heat pump run time before defrost.Use this option in heating mode and only if the coil differential pressure is not available, or the refrigerant and the outdoor air temperature are not available.

Maximum Defrost Time Displays the maximum time that defrost cycle can be ON.


Humidity ControlYou can control Humidity many ways in the Heat Pump Unit Controller; with a cooling coil, a humidifier or a dehumidifier. Table 28 describes the Humidity Control.Table 28: Humidity ControlField DescriptionSetpoint Displays the space humidity setpoint as a percentage.

Humidifier/Dehumidifier Minimum ON/OFF Time

Displays the period of time that must pass before the humidifier or dehumidifier can turn ON after turning OFF, or turn OFF after turning ON.Note: Humidifier/Dehumidifier ON/OFF time does not apply to

modulated humidifier and dehumidifier outputs.

Enable Dehumidifying Cycle Enables the dehumidifier using the cooling coil.

Disable in Heating Mode Disables the dehumidifier using the cooling coil in heating mode.

Cooling Override Value Displays the minimum value for the cooling internal control loop. In dehumidification process, this is the smallest value for the cooling outputs. For example, if you have one modulating cooling valve and the value for the cooling override is 55%, the valve always opens at 55% or more in dehumidification mode.

Fan Speed Override Value Displays the value for the fan speed in dehumidification mode. If you have 3 fan speeds, and you want speed 2 to be open, enter the value 66.66%, which corresponds to 2 fan speeds on a 3 fan speed possibility (2/3).


Network Input ConfigurationFigure 38 shows the Network Input Configuration dialog box. Table 29 describes the parameters.

Heartbeat AlarmsAn alarm occurs if the period between received values of these variables exceeds the value you enter into the Heartbeat column. For more information, see the Alarm Operation section.

Network Output ConfigurationThe Network Outputs screen enables you to control network traffic to reduce network congestion. Data is transmitted as quickly as is necessary for your application (Figure 39).

The Network Outputs screen enables you to control the frequency of network variable transmissions through several different parameters. On the Network Outputs Configuration screen you configure the following:

Table 29: Network Input ParametersField DescriptionHeartbeat Sets the maximum time between updates for the associated network input.

When the heartbeat interval has passed without an update, the network input enters the heartbeat failure state and its value becomes invalid.

Persistent Allows the network variable to remain in memory after a power failure and/or reset. Do not make frequently changing network variables persistent. See the Persistent Network Variables section for more information.

Figure 38: Network Input Configuration Screen


• Heartbeat period for network outputs

• Send on Delta quantity

• Throttle settings for several network outputs

You can also set the maximum send time and minimum send time for all other network variables. Table 30 describes the parameters.

Table 30: Network Output Configuration ParametersField DescriptionHeartbeat The maximum time period between transmissions of the network

variable.

Send on Delta Enter the amount of change of the value of the network variable that must occur before the variable is transmitted. The network variable is transmitted whenever this much change occurs.

Throttle Enter the minimum time period that must pass before a network variable is transmitted.

Other NVO The values entered in the Other NVO box affect all other network variable outputs that do not have individual values.Heartbeat: Enter the maximum time between transmissions of network variables.Throttle: Enter the minimum time between transmissions of network variables.

Figure 39: Network Output Configuration Screen


Object ManageThe Object Manage screen enables you to view the status of the LONMARK object and use LONMARK commands. To use this screen, you must be online, have the HPU Controller configured, and be in communication with the FX supervisory controller (Figure 40). Table 31 describes the Object Manage parameters.

Table 31: Object Manage Parameters (Part 1 of 2)Field DescriptionDevice State Displays the current state of the LONMARK object.

Object Status Displays the object status information from nvoUnitStatus. Messages such as Communications Failure or Electrical Fault appear here. A red icon indicates an active state and a gray icon indicates an inactive state.When the box Display Active Only is selected, only the red active status flags appear. The Object Status area is blank when the Heat Pump Unit Controller is in its normal state. For a description of each of the Object status pane messages, see the Object Status section.

Get Status Allows you to update status information in the object status list.

Clears Status Clears all status flags, removing all messages. Clicking Get Status retrieves new information. This can be used to check if a problem condition is solved.

Override ON Places the Heat Pump Unit Controller into the override state. Control outputs including the network variables and linked hardware outputs are set to their configured override value or state.

Override OFF Ends the Override state.

Figure 40: Object Manage


Object StatusThe Object Status messages are listed here with references to tables describing the causes.

Communication Failure

This message results from a heartbeat failure on a network variable input that sets the comm_failure bit of nvoStatus. See Table 13.

Enable Enables the controller after an override.

Disable Sets the LONMARK object to the disabled mode. In the disabled mode, control outputs are at their configured disabled state.

Request Allows advanced users to query LONMARK using the LONMARK object and commands.To query the LONMARK object, select a command from the drop-down list beside the request button. Click the Request button. Requests are handled by SNVT_obj_request. See Table 32 for values of SNVT_obj_request.

Table 32: Values for SNVT_obj_request1Value Identifier Meaning0 RQ_NORMAL Enable object and remove override

1 RQ_DISABLED Disable object

2 RQ_UPDATE_STATUS Report object status

3 RQ_SELF_TEST Perform object self test

4 RQ_UPDATE_ALARM Update alarm status

5 RQ_REPORT_MASK Report status bit mask

6 RQ_OVERRIDE Override object

7 RQ_ENABLE Enable object

8 RQ_RMV_OVERRIDE Remove object override

9 RQ_CLEAR_STATUS Clear object status

10 RQ_CLEAR_ALARM Clear object alarm

11 RQ_ALARM_NOTIFY_ENABLED Enable alarm notification

12 RQ_ALARM_NOTIFY_DISABLED Disable alarm notification

13 RQ_MANUAL_CTRL Enable object for manual control

14 RQ_REMOTE_CTRL Enable object for remote control

15 RQ_PROGRAM Enable programming of special configuration properties

16 RQ_CLEAR_RESET Clear the RESET_COMPLETE flag.

17 RQ_RESET Execute a reset sequence, set the RESET_COMPLETE flag when done.

1. Not all commands are available in the Heat Pump Unit Controller.

Table 31: Object Manage Parameters (Part 2 of 2)Field Description


Electrical FaultThis message indicates that a local hardware sensor is disconnected. The disconnect condition sets the electrical_fault bit of nvoStatus. See Table 14 for a list of the possible disconnected sensors.

Out of LimitsThis message indicates that a monitored point has exceeded limits set by the person who configured the device. The out-of-limits sets the out_of_limits bit of nvoStatus. See Table 16.

DisabledActive if the device has been disabled by pressing the Disable button.

In Alarm

Active if a communications failure or electrical fault has occurred or if any of the conditions in the Alarm Configuration window have been met.

In OverrideActive if the device has been placed into override by pressing the Override button.

Out of Service

Active when the LX-HPUL cannot control the temperature in the zone of the control because it is not receiving a space temperature or there is no slave input (nviSlave).

Network VariablesThe following text describes all network variables found in the Heat Pump Unit Controller.

nviApplicModeUse this network variable input to coordinate the Heat Pump Unit Controller with the following:

• an air handler controller

• any other supervisory controller

• a human interface device

See Table 33 for nviApplicMode values.


Type: SNVT_hvac_mode (108)

nviCoilDiffPressTransmits coil differential pressure from a network device to the Heat Pump Unit Controller. Network values has priority over local sensor values.

Type: SNVT_press_p (113)

Table 33: nviApplicModeValue Identifier Notes0 HVAC_AUTO Controller automatically changes between application

modes

1 HVAC_HEAT Heating only

2 HVAC_MRNG_WRMUP Application-specific morning warm up

3 HVAC_COOL Cooling only

4 HVAC_NIGHT_PURGE Application-specific night purge

5 HVAC_PRE_COOL Application-specific pre-cool1

1. Not supported in the Heat Pump Unit Controller.

6 HVAC_OFF Controller not controlling outputs

7 HVAC_TEST Equipment being tested1

8 HVAC_EMERG_HEAT Emergency heat mode1

9 HVAC_FAN_ONLY Air not conditioned, fan turned on

10 HVAC_FREE_COOL Cooling with compressor not running1

11 HVAC_ICE Ice-making mode1

0xFF HVAC_NUL Value not available


nviDischargeTempTransmits discharge temperature from a network device to the Heat Pump Unit Controller. Network values have priority over local sensor values.

Type: SNVT_temp_p (105)

nviEmergCmdUse this network variable input to command the Heat Pump Unit Controller into different emergency modes. It is typically set by a supervisory node. See Table 34.

Type: SNVT_hvac_emerg (103)

nviExtCmdOutputxThese network variable inputs receive the output signal (state and percentage) to control any output that is unassigned and configured through the controller configuration wizard. They are listed following the output number (nvoExtCmdOutput1, nvoExtCmdOutput2,...).

Type: SNVT_switch (95)

nviFanSpeedCmdThis network variable input receives the fan speed demand. It receives a value between 0-100% and a state of 0-1. For example, for three fan speeds: fan speed 1 starts when nviFanSpeedCmd is over 33.33%, fan speed 2 starts when nviFanSpeedCmd is over 66.66%, and fan speed 3 starts when nviFanSpeedCmd equals 100.00%. To start, the field of the nviFanSpeedCmd must be ON, state 1.


nviFanStateThis network variable input receives the fan state. When state and value are not set to zero, the fan state is considered ON. When state or value is set to zero, the fan state is considered OFF.


Table 34: nviEmergCmdValue Identifier Actions0 EMERG_NORMAL Normal operation

1 EMERG_PRESSURIZE1

1. Not supported in the Heat Pump Unit Controller.

The damper moves to the fully open position

2 EMERG_DEPRESSURIZE The damper moves to the fully closed position

3 EMERG_PURGE1 The damper moves to the fully open position Fan, heating, and cooling are turned OFF

4 EMERG_SHUTDOWN Fan, heating, and cooling are turned OFF

5 EMERG_FIRE1 ---

0xFF EMERG_NUL Value not available


nviHotWaterThis network variable input receives the water state. Water state refers to whether the water is hot or cold.

When state and value are not set to zero, the water state is hot. When state or value is set to zero, the water state is cold.


nviOccCmd & nviOccManCmdUse these network variable inputs to command the Heat Pump Unit Controller object into different occupancy modes.

Type: SNVT_occupancy (109); SNVT_tod_event (128)

The network variable nviOccCmd commands the Heat Pump Unit Controller to change modes according to the value of the variable. The value of nviOccCmd itself can be changed by a network schedule or a manual change.

While in any mode, the Heat Pump Unit Controller can enter a heating or cooling state as required to maintain the space within the limits of the setpoints.

nviOutdoorTempThis network variable input receives the outdoor air temperature.

nviPumpStateThis network variable input receives the pump state.

When state and value are not set to zero, the pump state is considered ON. When state or value is set to zero, the pump state is considered OFF.


nviRefrigTempThis network variable input transmits refrigerant temperature from a network device to the Heat Pump Unit Controller. Network values have priority over local sensor values.


Table 35: Values of nviOccCmd and ModesValue Identifier Heat Pump Unit Controller Mode0 OC_OCCUPIED Occupied Mode

1 OC_UNOCCUPIED Unoccupied mode

2 OC_BYPASS Bypass mode

3 OC_STANDBY Standby mode

0xFF OC_NUL Invalid data


nviSetPointThis network variable input changes the temperature setpoints for the occupied and standby modes via the network. The individual heating and cooling setpoints for the occupied and standby modes are calculated from nviSetPoint. See The Effect of nviSetPoint on the Active Setpoints section for more information.


nviSetPtOffsetThis network variable input shifts the temperature setpoint by adding the value of nviSetpointOffset to the current setpoint. This network variable operates only on occupied and standby setpoints and does not affect the unoccupied setpoint. See The Effect of nviSetPoint on the Active Setpoints section for more information.


nviSheddingThis network variable input reduces the Heat Pump Unit Controller power consumption. For example, if nviShedding is set to 25%, then heating and cooling do not exceed 75%.

Type: SNVT_lev_percent (81)

nviSlaveThis network variable input forces the Heat Pump Unit Controller to follow the demands of another Heat Pump Unit Controller. It is typically bound to the nvoUnitStatus of the other Heat Pump Unit Controller.

Type: SNVT_hvac_status (112)

nviSpaceRHThis network variable input transmits space humidity from a network device to the Heat Pump Unit Controller. Network values have priority over local sensor values.


nviSpaceTempThis network variable input transmits space temperature from a network device to the Heat Pump Unit Controller. Network values have priority over local sensor values.



nviWaterTempThis network variable input transmits water temperature from a network device to the Heat Pump Unit Controller. Network values have priority over local sensor values. If both nviHotWater and nviWaterTemp are received from the network, nviHotWater has priority over nviWaterTemp.


nvoCtrlOutputThese network variable inputs send the output signal, whether state or percentage, to any actuators.

They are listed following the output number (nvoCtrlOutput1, nvoCtrlOutput2, …).


nvoDischargeSetPtThis network variable output sends the discharge setpoint in use by the heat pump object.


nvoEffectSetPtThis network variable output sends the effective setpoint in use by the heat pump object.


nvoFanSpeedThis network variable output sends the fan speed.


nvoHPalarmTable 36 organizes the associated programmatic names and Bit numbers for nvoHPalarm. For more information about this network variable, see the Alarm Procedure section.

Type: SNVT_state_64 (165)


Format: UNVT_hp_alarmsTable 36: nvoHPalarm (Part 1 of 2)Programmatic Name Bit

NumberMeaning When Bit Is Set

nviSpaceTempHeartBeat 0 Heartbeat failure reported from nviSpaceTemp

nviApplicModeHeartBeat 1 Heartbeat failure has occurred in nviApplicMode

nviSetPtOffsetHeartBeat 2 Heartbeat failure has occurred in nviSetPtOffset

nviOccCmdHeartBeat 3 Heartbeat failure has occurred in nviOccCmd

nviWaterTempHeartBeat 4 Heartbeat failure has occurred in nviWaterTemp

nviHotWaterHeartBeat 5 Heartbeat failure has occurred in nviHotWater This network variable input transmits the water state: hot or cold

nviDischargeTempHeartBeat 6 Heartbeat failure has occurred in nviDischAirTemp

nviFanStateHeartBeat 7 Heartbeat failure has occurred in nviFanSpeedCmdState

nviSheddingHeartBeat 8 Heartbeat failure has occurred in nviShedding

nviSlaveHeartBeat 9 Heartbeat failure has occurred in nviSlave

nviOutdoorTempHeartBeat 10 Heartbeat failure has occurred in nviOutdoorTemp

nviSpaceRHHeartBeat 11 Heartbeat failure has occurred in nviSpaceRH

nviRefrigTempHeartBeat 12 Heartbeat failure has occurred in nviRefrigTemp

nviCoilDiffPress 13 Heartbeat failure has occurred in nviCoilDiffPress

nviFanSpeedCmdHeartBeat 14 Heartbeat failure has occurred in nviFanSpeedCmd

nviPumpStateHeartBeat 15 Heartbeat failure has occurred in nviPumpState

nviExtCmdOutputxHeartBeat 16-21 Heartbeat failure has occurred in nviExtCmdOutput

SpaceTempSensorFault 32 Space temperature sensor is disconnected for longer than 30 seconds

DischargeTempSensorFault 33 Discharge temperature sensor is disconnected for longer than 30 seconds

OutdoorTempSensorFault 34 Outdoor temperature sensor is disconnected for longer than 30 seconds

RefrigerantTempSensorFault 35 Refrigerant temperature sensor is disconnected for longer than 30 seconds

WaterTempSensorFault 36 Water temperature sensor is disconnected for longer than 30 seconds

SetpointOffsetElecFault 37 Setpoint offset is disconnected for longer than 30 seconds

LowSpaceTemp 38 Space temperature is lower than the active heating setpoint by more than the offset for a time period longer than the alarm delay

HighSpaceTemp 39 Space temperature is higher than the active heating setpoint by more than the offset for a time period longer than the alarm delay

LowDischargeTemp 40 The discharge temperature is lower than the low limits setpoint for a time period longer than the alarm delay

High DischargeTemp 41 The discharge temperature is higher than the high limits setpoint for a time period longer than the alarm delay


nvoHPstateThis network variable output sends the heat pump status. It provides configuration errors and mode status.

Type: SNVT_state_64 (165). Format: UNVT_hp_state

LowSpaceRH 42 The space humidity is lower than a setpoint by more than the humidity offset for a time period longer than the alarm delay

HighSpaceRH 43 The space humidity is higher than a setpoint by more than humidity offset for a time period longer than the alarm delay

FanStateMismatch 44 The fan state is different than the fan output for a time period longer than the alarm delay

PumpStateOff 45 The pump state is OFF, and the pump output is ON for a time period longer than the alarm delay

AuxiliaryLowAlarm 46 The auxiliary alarm input is lower than the low limit setpoint for a time period longer than the alarm delay

AuxiliaryHighAlarm 47 The auxiliary alarm input is higher than the low limit setpoint for a time period longer than the alarm delay

Emergency 48 The Heat Pump Unit Controller is in emergency mode

Table 37: nvoHPstate (Part 1 of 2)Programmatic Name Bit


OutofService 0 The device is out of service There is no space temperature sensor configured, or nvislave is not bound

EmergencyMode 1 Emergency mode is ON It is received from the nviEmergCmd or sent by the emergency contact

HotWater 2 The water is hot

MecCoolingEnabled 4 Mechanical cooling is enabled This occurs when the outdoor temperature is higher than the mechanical minimum outdoor temperature

CtrlOutputxOverridden 8–14 The heat pump object output is overridden

HwOutputxOverridden 15–21 The hardware output is overridden

DupDischrgTempCfgError 39 Duplicate discharge air temperature sensor configuration error

DupOutTempTempCfgError 40 Duplicate outdoor air temperature sensor configuration error

DupRefrigTempCfgError 41 Duplicate refrigerant temperature sensor configuration error

DupWaterTempCfgError 42 Duplicate water temperature sensor configuration error

DupSpaceHumidCfgError 43 Duplicate space humidity sensor configuration error

Table 36: nvoHPalarm (Part 2 of 2)Programmatic Name Bit



nvoHwInputThese network variable outputs send the input value over the network with their own changeable SNVT type. They are numbered following the input number (nvoHwInput1, nvoHwInput2,...).

Type: Changeable type

nvoOccStateThis network variable output sends the occupancy state used by the heat pump object.

Type: SNVT_occupancy (109)

nvoSpaceTempThis network variable output sends the space temperature used by the heat pump object.

DupCoilDiffPressCfgError 44 Duplicate coil differential pressure sensor configuration error

DupAuxAlarmCfgError 45 Duplicate auxiliary alarm sensor configuration error

DupFanStateCfgError 46 Duplicate fan state sensor configuration error

DupFanSpdSelCfgError 47 Duplicate fan speed selector sensor configuration error

DupModeSelCfgError 48 Duplicate mode selector sensor configuration error

DupPumpStateCfgError 49 Duplicate pump state sensor configuration error

DupOccCntctCfgError 50 Duplicate occupancy contact sensor configuration error

DupBypassCntctCfgError 51 Duplicate bypass contact sensor configuration error

DupWindowCntctCfgError 52 Duplicate window contact sensor configuration error

DupCoilFrostCfgError 53 Duplicate coil frost contact sensor configuration error

DupEmergCntctCfgError 54 Duplicate emergency contact sensor configuration error

FanSpeedCfgError 55 Fan speeds configuration error

NoFanOutputCfgError 56 No fan output configuration error

NoHeatOrCoolCfgError 57 No heat or cooling output configuration error

HeatValveCfgError 58 Heating valve configuration error

CoolValveCfgError 59 Cooling valve configuration error

HeatCoolValveCfgError 60 Heating and cooling valve configuration error

HeatStagesCfgError 61 Heating stages configuration error

CoolStagesCfgError 62 Cooling stages configuration error

RevValvWOCoolCfgError 63 Reversing valve without cooling stages configuration error

Table 37: nvoHPstate (Part 2 of 2)Programmatic Name Bit




nvoTerminalLoadThis network variable output sends the energy demand of the heat pump in percentage. Positive values are cooling demand and negative values are heating demand.

Type: SNVT_lev_percent (81)

nvoUnitStatusThis network variable output sends all of the following information simultaneously:

• operating mode

• primary heating state as a percentage

• secondary heating state as a percentage

• cooling state as a percentage

• fan state as a percentage

• heat pump alarm state

Type: SNVT_hvac_status (112)


Standard Network Variable Types (SNVT)Listed here are some of the SNVTs more commonly used in the Heat Pump Unit Controller configuration wizard.

SNVT_hvac_emerg (103 HVAC Emergency Mode)Use for heating, ventilating, and air conditioning applications.

SNVT_hvac_mode (108)Use for heating, ventilating, and air conditioning applications.

Table 38: SNVT_hvac_emergSNVT_hvac_emerg DescriptionField emerg_t

Measurement Emergency Mode

Field Type Category Enumeration

Type Size 1 byte

Valid Type Range emerg_t

Type Resolution 1

Units N/A

Invalid Value EMERG_NUL

Raw Range emerg_t

Scale Factor N/A

File Name SNVT_EM.H

Default Value N/A

Table 39: SNVT_hvac_modeSNVT_hvac_mode DescriptionSNVT Index 108

Measurement hvac_t


Type Size 1 byte

Valid Type Range hvac_t

Type Resolution 1

Units N/A

Invalid Value HVAC_NUL

Raw Range hvac_t

Scale Factor N/A

File Name SNVT_HV.H

Default Value N/A


SNVT_hvac_status (112) Use for heating, ventilating, and air conditioning applications. Table 40: SNVT_hvac_statusSNVT_hvac_status DescriptionSNVT Index 112

Measurement HVAC Status

Field Type Category Structure

Type Size 12 bytes

Table 41: SNVT_hvac_status StructureField Measurementmode hvac_t

heat_output_primary signed long

heat_output_secondary signed long

cool_output signed long

econ_output signed long

fan_output signed long

in_alarm unsigned short

Table 42: HVAC Status ModeHVAC Status Mode DescriptionField mode

Measurement hvac_t


Type Size 1 byte

Valid Type Range hvac_t

Type Resolution 1

Units N/A

Invalid Value HV_NUL

Raw Range hvac_t

Scale Factor N/A

File Name SNVT_HV.H

Default Value N/A


Table 43: Primary Heat OutputPrimary Heat Output DescriptionField Heat_primary_output

Measurement Primary Heat Output

Field Type Category Signed Long

Type Size 2 bytes

Valid Type Range -163.840 – 163.830

Type Resolution 0.005

Units Percent of full scale

Invalid Value 32,767 (0x7FFF)

Raw Range -32,768 – 32,766(0 x 8000 – 0 x 7FFE)

Scale Factor 5, -3, 0S = a*10b*(R+c)

File Name N/A

Default Value N/A

Table 44: Secondary Heat OutputSecondary Heat Output DescriptionField heat_output secondary

Measurement Secondary Heat Output


Type Size 2 bytes





Raw Range -32,768 – 32,766


File Name N/A

Default Value N/A


Table 45: Primary Cooling OutputPrimary Cooling Output DescriptionField cooling_output

Measurement Cooling Output


Type Size 2 bytes





Raw Range -32,768 – 32,766(0 x 8000 – 0 x 7FFE)


File Name N/A

Default Value N/A

Table 46: Economizer OutputEconomizer Output DescriptionField econ_output

Measurement Economizer Output


Type Size 2 bytes





Raw Range -32,768 – 32,766(0 x 8000 – 0 x 7FFE)


File Name N/A

Default Value N/A


Alarm StateZero means that the unit is not in an alarm state. 255 (0xFF) means that alarming is disabled. All other values, between 1 and 254, inclusive, mean that the unit is in the alarm state. The values, between 1 and 254, are manufacturer specific as to their meaning, but all represent an alarm state.

Table 47: Fan OutputFan Output DescriptionField fan_output

Measurement Fan Output


Type Size 2 bytes





Raw Range -32,768 – 32,766(0 x 8000 – 0 x 7FFE)


File Name N/A

Default Value N/A

Table 48: Alarm State Alarm State DescriptionField month

Measurement In Alarm State

Field Type Category Unsigned Short

Type Size 1 byte





Raw Range -32,768 – 32,766(0 x 8000 – 0 x 7FFE)


File Name N/A

Default Value N/A


SNVT_lev_percent (81)

SNVT_occupancy (109)

Table 49: SNVT_lev_percentSNVT_lev_percent DescriptionSNVT Index 81

Measurement Percentage Level


Type Size 3 bytes



Units Percent of full scale, or parts per million (ppm)


Raw Range -32,768 – 32,766(0 x 8000 – 0 x 7FFE)


File Name N/A

Default Value N/A

Table 50: SNVT_occupancySNVT_occupancy DescriptionSNVT Index 109

Measurement occup_t


Type Size 1 byte

Valid Type Range occup_t

Type Resolution 1

Units N/A

Invalid Value OC_NUL

Raw Range occup_t

Scale Factor N/A

File Name SNVT_OC.H

Default Value N/A


SNVT_switch (95)

Switch DefinitionSwitch Definition is a structure that reports a percentage level or load value, and a discrete ON/OFF state. Separate fields report the percentage value and state. Use this type for both discrete (ON/OFF) and analog control.

You can use the value field to control the load’s value (for example, position, speed, or intensity) and use the state field to control whether the load is ON or OFF (enabled or disabled). When you use the state field as the output of a discrete sensor device, the OFF state is represented by a SNVT_switch network variable with state = FALSE and value = 0. The other discrete states are represented by state = TRUE and value > 0. When used as the output of a two-state sensor device, the ON state is represented by state = TRUE and value = 200 (meaning 100%).

When you use an SNVT_switch network variable with state = TRUE as the input of a two-state discrete actuator, it is interpreted as the ON state if value > 0, and as the OFF state if value = 0. In addition, a SNVT_switch input network variable with state = FALSE should be interpreted as the OFF state, whether or not value = 0. A state value of 0xFF indicates the switch value is undefined.

Table 51: SNVT_switchField DescriptionSNVT Index 95

Measurement Switch


Type Size 2 bytes

Table 52: SNVT_switch Input Network VariableValue (raw) State Two-State InterpretationAny 0 Off (0; 0)

0 1 Off (0; 1)

> 0 1 On (200; 1) 1

Any -1 (0 x FF) Invalid (no action)

Table 53: SNVT_switch Output Network VariableValue (raw) State Two-State Interpretation0 0 Off

200 (0xC8) 1 On

0 – 200(0 x C8) (any valid value)

-1 Invalid (NULL)


Table 54: SNVT_switch Value SNVT_switch Value DescriptionField Value

Measurement State


Type Size 1 byte

Valid Type Range 0 – 100

Type Resolution 0.5


Invalid Value N/A

Raw Range 0 – 100(0 – 0xC8)


File Name N/A

Default Value N/A

Table 55: SNVT_switch State SNVT_switch State DescriptionField State

Measurement State


Type Size 1 byte

Valid Type Range 0 – 100

Type Resolution 0.5


Invalid Value N/A

Raw Range 0 – 200(0 – 0xC8)


File Name N/A

Default Value N/A


SNVT_temp_p (105)

SNVT_tod_event (128)

Table 56: SNVT_temp_pSNVT_temp_p DescriptionSNVT Index 105

Measurement Temperature


Type Size 2 bytes



Units Degrees Celsius

Invalid Value 32,767(0x7FFF)

Raw Range -27,317 – 32,767(0x8000 – 0x7FFE)

Scale Factor 1, 2, 0S = a*10b*(R+c)

File Name N/A

Default Value N/A

Table 57: Occupancy Scheduling EventOccupancy Scheduling Event DescriptionSNVT Index 128

Measurement Time of day event


Type Size 4 bytes

Table 58: SNVT_tod_event: Current StateSNVT_tod_event: Current State DescriptionSNVT Index Current_state

Measurement occup_t


Type Size 1 byte


Type Resolution 1

Units N/A


Raw Range Occup_t

Scale Factor N/A

File Name SNVT_OC.H

Default Value N/A


Table 59: SNVT_tod_event: Next StateSNVT_tod_event: Next State DescriptionSNVT Index next_state

Measurement occup_t


Type Size 1 byte


Type Resolution 1

Units N/A


Raw Range Occup_t

Scale Factor N/A

File Name SNVT_OC.H

Default Value N/A

Table 60: SNVT_tod_event: Time to Next StateSNVT_tod_event: Time to Next State DescriptionSNVT Index time_to_next_state

Measurement Time to next state

Field Type Category Unassigned long

Type Size 2 bytes

Valid Type Range 0 – 65,535

Type Resolution 1

Units Minute of hour

Invalid Value N/A

Raw Range 0 – 65,535(0 – 0xFFFF

Scale Factor 1, 0, 0S = a*10b*(R+c)

File Name N/A

Default Value N/A

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