analog control system

Product Training Department

Engine Interface ModuleThe Engine Interface Module is a sealed, engine mounted module that providesswitching relays for the Starter Motor Solenoid, Glow Plug and Fuel Solenoid.Each of these circuits is protected with individual automotive fuses mounted in themodule. Individual LED’s illuminate when each circuit is energized in additionthese LED’s greatly aid when fault finding.This module is mounted on the engine with anti-vibration mounts and is easilyconnected to the engine via loom plugs. Use of the EIM means that heavycurrents such as Fuel Solenoid power are isolated from the control panel thusenabling individual protection of each of the circuits.

Item Description Item Description1. Glow Plug Symbol 8. Secondary Socket2. Fuel Symbol 9. Starter Solenoid Fuse3. Fuel Solenoid Fuse 10. Starter LED4. Fuel LED 11. Overspeed Set-up LED5. Main Connector Socket 12. Overspeed Adjuster6. Glow Plug Fuse 13. Starter Symbol7. Glow Plug LED

Engine Interface Module

Functional DescriptionThere are four versions of the Engine Interface Module available - the 12/24 voltEIM SR and the 12/24 volt EIM Plus.The EIM SR is the basic level module that provides all the switching functionality;the EIM Plus provides the same functionality as the EIM SR plus the additionalfeature of Overspeed Sensing and an Overspeed Trip Adjuster. A magnetic pick-up on the engine flywheel housing provides the speed signal to the EIM Plus.When an overspeed situation is sensed, the EIM Plus signals the 2001, 4001 or4001E generator set control panel to stop the engine. The Overspeed Trip Pointcan be easily set-up for 10% above the normal operating speed.The overspeed feature on the EIM Plus, including the magnetic pickup ismandatory for all the Autostart control panels except the Access 4000 (2001,4001 and 4001E).


Status IndicationLED’s on the module correspond to the Starter Motor Solenoid supply, the GlowPlug supply (where used) and the Fuel Control Solenoid supply. Each illuminatesto show that the indicated circuit is energized. A fourth LED (only operational onthe EIM Plus) is used to set-up the Overspeed Trip Point.

Starter Motor Solenoid (EIM SR)When the Keyswitch is turned to start, a relay in the module is energized providingpower to the Starter Motor Solenoid. When the Keyswitch is released the relay isde-energized and disengages the starter motor.

Starter Motor Solenoid (EIM Plus)During cranking the module receives a signal from the magnetic pick-up. Whenthe signal rises above 1090 Hz, the starter motor is disengaged and the EIM Plusswitches a zero volt signal to the generator set control panel to indicate that theengine is running.Should the crank speed be less than 12 Hz, the module will only allow a crank of0.6 seconds.If the engine speed falls below 350 Hz (i.e. the engine has stopped) the EIM Pluswill allow cranking only after a 5 second delay (lockout) which compliments thegenerator set control panel’s 3 attempt crank.

Glow Plug (pre-heat)When the relay is energized power is provided to the Glow Plug (where fitted).

Fuel Control SolenoidThe generator set control panel energizes a relay in the module that providespower to the Fuel Control Solenoid allowing fuel flow to the engine.

Overspeed Signal (EIM Plus only)The EIM Plus monitors the speed signal from the magnetic pick-up. If the enginespeed rises above a certain pre-settable value, the module sends a zero voltsignal to the generator set control panel to activate the Overspeed Fault circuitry.The Overspeed Set Point is factory set at 55Hz for 50Hz sets and 66Hz for 60Hzsets. This can be adjusted using the adjustment screw accessed through the holebeside the Overspeed Set-Up LED. While the engine is running at the ratedspeed (1500 rpm for 50Hz or 1800 rpm for 60Hz) the adjustment screw should beadjusted until the Overspeed Set-Up LED just goes out. This sets the overspeedvalue at 10% above the speed at which the generator set is operating.


Safety “Relay” FeatureThe EIM SR and EIM Plus provide a safety check for any damaged contacts (i.e.welded contacts) using a “safety” relay. When the emergency stop pushbutton onthe generator set control panel is pushed the EIM module automatically checksFuel Control Solenoid and Starter Motor Solenoid to see if they are welded shut.A dimly lit LED on the module indicates the contacts are damaged and the moduleshould be replaced.

Schematic Representation

Connector Pin Wire FunctionMain 1 51 Output to Starting SolenoidMain 2 58 Output to Glow PlugMain 3 53 Output to Fuel Control SolenoidMain 4 10 Glow Plug InputMain 5 + DC positive supplyMain 6 4 Starter Motor Input signal from control panelMain 7 5 DC negative supplyMain 8 3A Fuel Control input signal from control panelSecondary 1 56 Overspeed signal outputSecondary 2 57 MPU signal inputSecondary 3 54 Engine Relay signal OutputSecondary 4 5B Safety Relay DC negative


1001 Control System

System Operation

The generating set is started by turning the key on the front of the panel fullyclockwise. This will connect a positive supply to Run, Thermostart and Startwires. The thermostart and start signal wires go directly to the EIM via wires10 & 4, this will energise the glow plug (if applicable) and the starter motor.The fuel signal will connect onto wire 3A as soon as relay 1CR energises, thiswill occur due to contact 1CR/1 closing to link wire 7 to wire 3 via pin 22 onthe PCB.

The starter will be disengaged by the operator releasing the key which willspring back to keep a supply on the run wire only. This means we lose thesupply for the glow plug and starter motor.

The 1001 control panel is a key startoperated system which makes it onlyapplicable to prime power applicationsdue to no autostart capabilities. Thesystem offers two engine protections (i)High Engine Temperature and (ii) Low OilPressure. Both the protections arecontrolled externally to the control panelby the VDO engine mounted senders.The high engine temperature protectionwill activate at 103 – 105 degrees C (217– 221 F). The oil pressure protection willbe activated when the pressure drops to0.8 bar / 11.75 psi on the 0 – 5 bar modeland at 1.25 bar / 18.5 psi on the 0 – 10bar model.


The FPT (Fault Protection Timer) is enable via the run wire and will time outafter 15 seconds to close its contacts; this will enable the two protectionchannels. If the senders switch, then a zero volt signal is connected to R1 orR5 via pins 6 or 2 respectively. The applicable relay will energise and contactsR1/2 or R5/2 will switch to remove the supply to 1CR and hence the fuelcontrol solenoid, the set will shut down.

` Product Training Department

2001 Control System

The 2001 control panel offers autostart capabilities along with 5 engineprotection channels, 4 of which are configured as shutdowns and areallocated as Fail to Start, High Engine Temperature, Low Oil Pressure andEmergency Stop/Overspeed. The last channel of the five is a spare channelwhich may be configured at the factory when additional protections arerequested by the customer. Otherwise this channel may be configured by thecustomer as an alarm or a shutdown, the protection can also be FPT (FaultProtection Timer) enabled.

Fail to Start: This protection activates when the engine has been given a startsignal and the engine has failed to start. This is factory set to allow 3 attemptsto start, each attempt is made up of a 5 second crank cycle followed by a 5second rest period.

High Engine Temperature: The protection is activated externally by the VDOengine temperature sender. The sender typically switches between 103-105degrees C (217 – 221 F). This channel is FPT protected which means that itwill only become active 15 seconds after the engine has started.

Low Oil Pressure: The protection is activated externally by the VDO oilpressure sender. The sender typically switches at 0.8 bar/ 11.75 psi on the 0-5 bar model and 1.25 bar/18.5 psi on the 0-10 bar model. This protection isalso FTP protected.

Emergency Stop/Overspeed: This channel combines two protections, theemergency stop will activate once the panel or enclosure (if applicable)emergency stop push button is pressed. The overspeed signal is controlled bythe EIM. Once the EIM via the Magnetic Pickup, determines the engine has


exceeded the setpoint, a signal is sent to the 2001 panel and the shutdownactivates.

Spare Channel: This protection channel can be configured as either alarm orshutdown by repositioning the blue two-prong link on the 2001 PCB. Theprotection may also be FPT protected by physically removing link 5A from thePCB.

Basic Operation

When the panel is powered by connecting a DC supply through fuse 5, thepositive supply is branched off 3 ways: (i) the glow plug (12v only), (ii) thePCB through pin 24 and (iii) the three position switch (Run/Stop/Auto).

(i) Once the thermostart button on the front of the panel is pushed thepositive will be connected to wire 10 through the n/o contact and thento the EIM to energise the glow plug.

(ii) The positive supply to the PCB through pin 24 will supply a +ve to thefault LED’s, once the lamp test button is pushed a –ve will also beconnected to the LED’s and they will illuminate.

(iii) When the three position switch is turned to the RUN position we will get+ve on wires 50 & 8. Wire 50 allows a + supply to the 5 faults relaysF1, F2…F5 through pin 4 on the PCB. The relays will not switch as nodc -ve signal is connected to the coil of the relays. Wire 8 will effectively become the RUN signal, it firstly goes through an/c contact on the emergency stop button, so if the button is locked in,the Run signal will not progress. Providing the button is not locked thenthe Run signal progresses along wire 11a through the remote stop linkand onto wire 11. Wire 11 will supply a signal to the battery volt meterand also enter the PCB through pin 17. The run signal now enters thefault array, the section of the schematic made up of F1/1, F2/1, F3/1,F4/1 and F5/1; these are contacts on the fault relays ie F2/1 is contact1 on fault relay 2.


The relays CR1, CR2 and CR3 (control relays) will energise providing we geta signal as far as link 2 i.e. none of the fault relays are energised. Due to CR1energising contact CR1/1 will now switch. This will allow a positive supply tothe hours run clock, oil pressure gauge, engine temperature gauge and towire 3A, this is the signal to the EIM to energise the fuel control solenoid.Simultaneously to this occurring we also get a positive supply through ER/2shown above, this will in turn supply CYT, DT and SMR.

CYT is a cyclic timer with two states On & Off, these are usually set for 5seconds each at the factory. When CYT is On contact CYT/1 closes allowinga supply to SMR (Starter Motor Relay). When CYT is in the Off state CYT/1will open and prevent SMR from energising. When SMR does energise duringthe On state of CYT, contact SMR/1 switches to allow a positive supply ontowire 4 this is the signal input to the EIM to engage the starter motor and crankthe engine.

0 5 10 15 20 25

off offoffCYT

SMR

DT

on on on


DT is the duration timer that will limit the number of unsuccessfully crankattempts the engine will be allowed to make. If DT is allowed to time out(factory set for 27.5 seconds) then contact DT/1 closes and connects a –vesupply to fault relay 1 (fail to start). The relay will energise and contact F1/1 inthe fault array will switch removing the signal from CR1 hence cancelling thefuel signal to the EIM. The Fail to Start LED will illuminate and the startingsequencing ends.

If the engine does fire during one of the crank cycles then we need to end thestarting sequence and disengage the starter motor, this is achieved with theuse of AR or ER. ER is the engine relay, it energises when it receives anegative supply to its coil from the EIM via wire 54. The EIM will output therequired –ve signal when the magnetic pickup fitted to the engine senses asignal of 1090Hz. Due to ER energising contacts ER/1 and ER/2 will switch,ER/1 removes any supply from reaching SMR and ER/2 enables the FPT(Fault Protection Timer) to start timing out. The FPT has a default value of 15seconds. If for some reason ER did not energise then AR will disengage thestarter. AR is the alternator relay and is energised by an ac supply to its coilvia wires 108 and 115. If AR gets an AC supply of 180 volts or more, then itsassociated contacts will switch. AR/2 removes any +ve signal from reachingCYT, DT & SMR. AR/3 enables the FTP timer and AR/4 opens to remove a–ve supply reaching F1 when the FPT relay energises and its contacts switch.

Autostart Mode

When the 3 position switch is turned to Auto a positive supply is connected towires 50 & 24. Wire 50 is again used to allow a supply to the LED’s for theLamp Test, wire 24 will connect through the ATS (automatic transfer switch).When the ATS enters the condition to start the generator it closes a contact tolink wire 24 to wire 8 and we now operate as if the 3 position switch is in theRun position

Protection Activication

To activate any of the five protection channels we require a –ve to reach thecorresponding relay. The relay will energise and at the same time the LEDilluminates. Due to the relay energising contact Fx/1 in the fault array willswitch and cause CR1 to de-energise hence cutting of the fuel supply to theengine.

Timer Adjustments

It is possible to make adjustments to the following timing circuits on the 2001PCB: Fault Protection Timer (FPT), On cyclic timer (CYTON), Off cyclic timer(CYTOFF) and duration timer (DT). To adjust the timers we turn theassociated potentiometer, the default settings for the four timers are.


Ref. No Timer Range Settings Tolerance

1 FPT 1sec - 70sec 15sec +/- 1sec2 DT 1sec - 90sec 27.5sec +/- 2.5sec3 CYT ON 0.25sec - 20sec 5sec +/- 1sec4 CYT OFF 0.25sec - 20sec 5sec +/- 1sec

14

3

2


4001 & 4001E Control Systems

The 4001 and 4001E series control systems provide for automaticstarting and stopping of the generator set from a remote signal as wellas manual starting and stopping. This makes it appropriate for standbygenerating systems.On the 4001 and 4001E systems we have the same basic protectionsas that on the 2001 control system with the addition of an alarmprotection for Low Battery Voltage. On 4001E series control systemsthere are additional alarms for Approaching Low Oil Pressure,Approaching High Engine Temperature, Battery Charger Failure andNot in Auto Mode. Both systems have spare additional protectionchannels as detailed below..

For the 4001 Series Control System, theFault Indicating Lamps are grouped onthe control panel as follows:-

L1 Fail To Start ShutdownL2 High Engine Temperature

ShutdownL3 Low Oil Pressure ShutdownL4 Overspeed ShutdownL5 Additional ShutdownL6 Low Battery AlarmL7 Additional Alarm

For the 4001E Series Control Systemsnine additional Fault Indicating Lampsare included on the separate 4001Eexpansion PCB which are grouped onthe control panel as follows:-

L8 Not In Auto AlarmL9 Approaching High Engine

Temperature AlarmL10 Approaching Low Oil Pressure

AlarmL11 Battery Charger Failure AlarmL12 Programmable Channel 1L13 Programmable Channel 2L14 Programmable Channel 3L15 Programmable Channel 4

L16 Additional Shutdown


Indicators L12-L14 are programmed for shutdown or alarm functionsusing the Dil switches on the PCBThe DIL switches are assigned as follows:Fault DilChannel SwitchL12 SW1L13 SW2L14 SW3L15 SW4The setting of these programmable Fault Indicator Lamps can bechecked on the PCB. With both poles in "SD" position, the faultchannel is configured as a shutdown. With both poles in "ALM"position, the fault channel is configured as an alarm.

Since these control systems are designed for automatic starting, theyare fitted with connections for remote control. Included are terminalsfor Remote Emergency Stop and an interface to an Intelligent LoadTransfer Panel (MTi) or Automatic Transfer Switch (ATS). Additionally,the 4001 and 4001E Series Control Systems are fitted with an interfaceto Remote Annunciators

Basic System Operation

The 4001E system is constructed by using the same PCB as that onthe 4001 plus the addition of an expansion board. This means that thebasic operation of both the systems is the same.

When the main control panel fuse is fitted the panel is powered by thebattery. The battery positive is branched of to four areas (i) to the glowplug , if applicable (ii) to terminals to be connected to the ATS (iii) to thePCB via pin 24 (iv) 3 position switch.


(i) When the thermostart button mounted on the front of the panel ispushed a signal will be sent to the EIM via wire 10 to energise the glowplug (if applicable).

(ii) The supply to terminals is for the ATS, when the ATS wants to start thegenerator it will close a n/o contact and link 7 to 24.

(iii) The supply to the PCB via pin 24 will enable the Low Battery Voltagemonitoring circuit and also provide a supply for the LED’s for the LampTest.

(iv) The supply to the three-position switch plays no role until run or auto isselected.

RUN Mode

When the switch is turned to the run position wire 7 will be connectedonto wire 8; this then goes through a n/c contact on the emergencystop button. If the button is locked in we do not progress. Provided theemergency stop is not locked in the run signal will transfer onto wire 9.Wire 9 is linked to wire 11 by the remote stop link. Wire 11 will supply avoltage to the battery volts gauge for display and also enters the PCBvia pin 16.On drawing D20449 we can see that the signal entering the PCB viapin 16 sends a supply to the oil and coolant gauges via pins 8 and 12.The signal also energises CR1 and CR2 via the fault array (F1R/1 toF5R/1).When CR1and CR2 energise contacts CR1/1 switches a positivesupply to wire 3 via pin 3 and CR2/1 switches to enable a supply toCYT, DT and SMR. SMR will energise when contact CYT/2 closes i.e.during the CYTON cycle, this allows SMR/1 to close and send a startermotor signal to the EIM through pin 23 onto wire 4.DT will limit the number of cranks as discussed in the system operationof the 2001-control system and either ER or AR once again disengagesthe starter motor.

Autostart Mode

When the three-position switch is turned to the auto position wire 8 willconnect to wire 13 and the system will wait on the ATS to close thecontact between wire 7 and 24 before anything further happens. Whenthe ATS closes the contact onto wire 24 a positive supply enters thePCB via pin 15 which will energise MSRA (mains sensing relayauxiliary). Contact MSRA/1 closes and allows a positive supply ontowire 13 via pin 17, wire 8 is connected to wire 13, as stated above andwe are now operating as if the 3 position switch is in the run position.


When the ATS removes the link between 7 and 24, MSRA de-energises but the set does not stop because we will still have a positivesignal on wire 13 due to contacts CR2/2 and ROT/2. When timer ROT(run on timer) times out, ROT/2 opens and the set shuts down due toCR de-energising and removing the fuel supply. The ROT is enabledwhen MSRA de-energises and MSRA/2 closes to enable the timer.

Protection Activation

The protection channels are activated by allowing a dc negative to the faultrelay coil, which will switch the contacts on the relay. This will also illuminatethe corresponding LED, the protection is cleared and reset by pressing thelamp test / reset button which will temporarily break the supply to the relay.

The two spare channels, L5 and L7 are permanently allocated as shutdownand alarm respectively.

Timer Adjustment

It is possible to make adjustments to the following timing circuits on the 4001and 4001E PCB’s:

Fault Protection Timer (FPT), On cyclic timer (CYTON), Off cyclic timer(CYTOFF), duration timer (DT), and the run on timer (ROT). The range anddefault settings are shown:

Ref. No Timer Range Settings Tolerance

1 CYT ON 0.25sec - 20sec 5sec +/- 1sec2 CYT OFF 0.25sec - 20sec 5sec +/- 1sec3 ROT 3 – 330sec 240sec +/- 15sec4 DT 1sec - 90sec 27.5sec +/- 2.5sec6 FPT 1sec - 70sec 15sec +/- 1sec

4 3 2 1

5 6 7


In addition to this we can adjust the setpoint of the Low Battery Volts trip pointby adjusting the pot shown as item 7. This is usually set for 10.75 volts for 12vsystems and 22.75 for 24v systems. This alarm has a built in time delay,LBVT default set for 60 seconds to prevent spurious tripping of the alarm suchas when the engine is cranking.

Link 1 (item 5) should be removed on the 4001 PCB when an expansionboard is fitted i.e. 4001E.

Four additional Alarm circuits are provided on the 4001E Series ControlSystem. The Approaching Low Oil Pressure and Approaching High EngineTemperature alarms work off the sensors fitted for the gauges. Thetemperature alarm is factory set to go off at 95°C ± 1°C but may be adjustedusing the pot on 4001E PCB. The Not in Auto Mode Alarm senses theposition of the Control Switch via P2. The Battery Charger Failure Alarmdetects low voltage from the charger. This level (BCV) is factory set at 13volts for 12-volt systems and 26 volts for 24-volt systems. This alarm can beoperated in one of 3 modes depending on the position of Link 6 on the 4001EExpansion PCB (see diagrams below):

Mode 1: Link in Position 1�

�

�

For generator sets with trickle charger and engine driven chargingalternators. In this position the charger failure circuit monitors theengine mounted charger when the engine is running and the tricklecharger when the engine is off.Mode 2: Link in Position 2

�

�

�

For generator sets fitted with AC powered chargers only (noengine driven charging alternator.)Mode 3 Link in Position 3

�

�

�

For generator sets with no battery charger fitted. In this position thecharger failure circuit is disabled.


Item Description

1 TEMP: Approaching High Engine Temperature Set PointSet: 95°C ± 1°C

2 SW1: Shutdown/Alarm Selector for Fault L123 SW2: Shutdown/Alarm Selector for Fault L134 SW3: Shutdown/Alarm Selector for Fault L145 SW4: Shutdown/Alarm Selector for Fault L156 BCT: Battery Charger Timer Set

Range: 3-330 secondsSet: 180 ± 15 seconds

7 IDLT: Input Delay Timer SetRange: 0.25-30 secondsSet: 1 ± 0.5 seconds

8 BCV: Battery Charger Failure Detection Set PointSet: 11.75 volts for 12 volt systems 22.25 volts for 24 volt systems

9 LINK 6: Battery Charger Failure Operating Mode

987

6

5

4

3 2

1

Remote Annunciators

There are two remote analogue annunciator panels to operate with the 4001and 4001E series control panels. These are the Pan 4 and Pan 5 RemoteAnnunciators.

The signals from the interface are theensuring that the correct signal is conthe remote annunciator. The remote adetailing the faults as listed on the gen

On the PCB’s inside the remote annuchange the colour of the fault LED’s frgreen. Also each channel can be progactivated.

The supply for the remote annunciatoThe positive supply is taken from pin 1terminal 9 (Pos) on the annunciator Ptaking a wire 5 from the control panel

The operating voltage of the remote apanel but the voltage can be determin

The 4001 & 4001E systems are fitwith the ribbon/field cable interfaceboard. The purpose of this interfacto allow the required signals to betransmitted from the control panel the remote annunciator. Signals frboth the 4001 & 4001E PCB’s areterminated on this board and thedetails given in tabular form on thecontrol panel schematic

The Pan 4 option has 8 channels andis used for the 4001 system were asthe Pan 5 has 16 channels and isused in conjunction with the 4001E.

The system operates when anegative signal is switched to theremote annunciator panel from the4001/4001E control panel and thecorresponding LED is illuminated.


n hardwired to the remote annunciatornected to the corresponding channel onnnunciator will have an engraved fasciaerator control panel fascia.

nciator the customer has the ability toom the following choices: red, yellow orrammed to sound a siren when

r panel is taken from the interface board.1 on the interface and connected to

CB, the negative supply is obtained byto terminal 10 on the annunciator PCB.

nnunciator panel is not indicated on theed by checking the rating of the relays

ted

e

toom


on the annunciator PCB. This will state 24USB or 12USB depending onwhether the system is 12 or 24 volts.

The remote annunciator panels may have optional remote start switches oremergency stops fitted. If the remote start switch is fitted then it is necessaryto connect this switch to wires 7 & 24 in the control panel. If the emergencystop is fitted then the remote stop link should be removed in the control paneland wires 9 & 11 connected across to the remote annunciator panel.

The distance that the remote annunciator can be mounted from the gensetdepends on the voltage of the system and also the type of wire that is used toconnect both parts of the system. To calculate the maximum length we firstdetermine the operating voltage and how many channels we are using either8 or 16. The maximum voltage drop for 12v systems is 2v and for 24vsystems the maximum drop is 4v. We also have to allow 100mA per channel.We then apply Ohms law to get the overall resistance of the connecting cable.

Example: 12v Pan 4 gives

Resistance = max volts drop/(100mA x number of channels)

Resistance = 2v / 800mA

Resistance = 2.5 ohms

We need to now refer to the cable manufactures handbook for the selectedcable or an IEE/IEEE data table to determine the resistance per yard or metrefor the selected cable. The resistance that we calculated is then divided by themanufacturers figure to obtain the theoretical maximum length that theannunciator can be from the generator.

If we were using 14wg (2.1mm2) then the resistance is approximately 0.00307ohms per foot. This would then give us a maximum length of 815 feet / 272yards or 247 metres. Allowances should be made as data tables quoteresistance at a given temperature and you must allow for variance in theambient temperature.


Automatic Transfer Switches

When a generator set is installed to automatically provide standby power in the event ofmains failure, a load transfer panel or automatic transfer switch is required. The transfer panelis designed to sense when the mains has failed, signal the generator set to start, switch theload from the failed mains to the generator set and then switch it back after the mains is re-established. See below.

Function of a Load Transfer Panel

MTi Load Transfer Panel

The MTi Load Transfer Panel is a microprocessor based control system that is designed towork with Autostart Control Systems (2001, 4001, 4001E, 6101, 6201 and Access 4000Series) to form an automatic mains failure system. Only a two wire interconnection isnecessary between the generator set control panel and the MTi panel making the installationvery simple. The two wires are identified for all Autostart Control Systems as:-

MTi C/O SystemPanel

2001 series panel 4001 Series panel 4001E series panel

7 & 24 8 & 24 7 & 24 7 & 24

MTi C/O SystemPanel

Access 2000 and 4000series panel

6101 Series panel 6201 series panel

7 & 24 5 & 24 13 & 93 7M & 90

General Operation

When the micro controller is operating correctly the green heartbeat LED will flash. The MTichangeover system monitors the mains voltage, if the control system detects that the mainssupply voltage has fallen below a predetermined setpoint a timer is enabled, 2MT (mains failtimer). Also the corresponding red LED will illuminate to indicate the phase on which theundervoltage was sensed. If the mains is still below the setpoint when 2MT has timed outthen the MTi will open the mains contactor to disconnect the mains from load. Then the N/Ocontact will close to link the two wires of the generator control system autostart (as shownabove). The generator will start and once up to rated speed and voltage a timer will beenabled, AT. AT is the alternator timer which will time out and then allow the generatorcontactor to close, the load will now be supplied by the genset.

The MTi will still monitor the mains for when it returns. As soon as the mains returns and isabove a healthy level setpoint, 1MT (mains return timer) will be enabled. If the mains is still


present and within limits after 1MT times out the generator contactor will open to disconnectthe genset from mains. DBT (Deadband Timer) will now start to time and once complete themains contactor will close reconnecting the load to the mains again. The genset will continueto run, due to ROT (run on timer), this is enabled as soon as the generator is taken off loadand the purpose of this is so that the genset is allowed some time to run with no load forcooling purposes. Once ROT has timed out then the N/O contact connecting the two autostartwires will open and the generator will shut down awaiting the next mains fail.

Timer Settings

There are 5 main timers used on the MTi PCB. These are:

Timername

Timerfunction

Timer details Timerrange

DefaultSettings

2MT Mains failtimer

Time from mains failure to the issue of generatorstart signal

1s – 60s 6s

AT Alternatortimer

Time from generator available to generator contactorclose signal

0s – 60s 6s

1MT Mains returntimer

Time from mains available to generator contactoropen signal

2m40s –28m

2m40s

DBT Dead bandtimer

Time between generator contactor open signal andmains contactor close signal and vice versa

0s – 15s 7s

ROT Run OnTimer

Time from generator contactor open signal to genstop signal

3s – 8m 45s

The timers are changed using on board DIP switches SW1 and SW2 and are definedaccording to the diagram below.

Procedure for changing the timer settings

1. Remove all power from the board.2. Insert LINK 4 for 10 seconds to reset system.3. Set timer DIP switches as required.4. Remove LINK 4 and reconnect power to board.

Optional Remote Status Indication LED’s:

If fitted, this option allows a remote indication of the status LED’s that are mounted on the MTipanel. A 10 way ribbon cable connected to connector EC11 on the MTi PCB sends theappropriate signals to a matching status display PCB


Mains/Generator voltage level threshold

The MTi allows the mains and generator fail/return points to be set on site without the use ofvariable AC supplies. This is done with use of a calibrated multimeter and applying themeasured DC values to an equation to calculate the exact AC setpoint.

There are six potentiometers on the PCB called MA, MB, MC, GA, GB and GC. These potsare for adjusting the setpoint for each phase sensed from the mains and generator. The failsetpoint is set typically 10% lower than the rated line to neutral voltage. The return setpoint isthen automatically set for 4.5% above the fail point. To give an example:

If the voltage system was 415/240v the fail point would be 240 x 0.9 = 216v. The healthyreturn point would then be 216 x 1.045 = 226v.

Procedure for setting mains/gen threshold

Mains

1. Connect a calibrated DC meter test points PHA and GND. (see diagram over)

2. Adjust pot MA to bias measured DC voltage to desired level based on the formula

VDC = (Vac x 0.028) – 0.361

To carry on the example we were required to set the fail point for 216v, this would equate to adc voltage of 5.687v.

3. Repeat for phase B & C using test point PHB and pot MB for phase B, use PHC and MCfor phase C.

Generator

1. Connect a calibrated DC meter test points GENA and GND.

2. Adjust pot GA to bias measured DC voltage to desired level based on the formula

VDC = (Vac x 0.028) – 0.361

3. Repeat for phase B & C using test point GENB and pot GB for phase B, use GENC andGC for phase C.

Control Switches

The main control switch on the front of the panel has three positions:-

AUTO – The normal position for automatic operation.

TEST WITHOUT TRANSFER – For testing the generator set without connecting the load.This switch will start the generator immediately.

TEST WITH TRANSFER – For testing the generator set with the load connected. This switchsimulates a mains failure by disconnecting a phase from the PCB and the MTi will operate asfor a mains failure.

In addition to the main control switch there is a “Control Bypass” key switch for use by servicepersonnel only. In the “normal” position the MTi operates normally. The other two positionsallow for the service personnel to manually connect the load to the operating generator set or


to the mains supply. This switch would be used if the MTi PCB has been damaged or thetimer settings are to be changed.

Status LED’sThe front of the door has the status LED’s, maintenance switch and main control switch.There are four status LED’s as shown.Pressing the Lamp Test Button, located on the front of the door, will illuminate them fortesting.

MTi Series Load Transfer Panel Status Display

Item Description

1. “Mains Available” Status LED2. “Mains on Load” Status LED3. “Generator on Load” Status LED4. “Generator Available” Status LED

Item Description Item Description

1 Link 4 – Timer reprogramming 5 Gen test points GENA, GENB & GENC2 MA, MB & MC 6 GND Test Point3 GA, GB & GC 7 Voltage selector link 24 Mains test points PHA, PHB &PHC 8 Voltage selector link 3

5

2 3

4

6

78

1

Documents

analog control system