Hydra Nitrate Manual B1814 - Electro-Chemical Devices Nitrate Manual F14.pdf · 2. Check the contents of the shipping container with the items and quantities shown on the packing

Rev: D – 07/11

ELECTRO-CHEMICAL DEVICES

Instruction Manual

Hydra Nitrate Analyzer

Page ii HYDRA NO3--N

PREFACE

Purchasing products from Electro-Chemical Devices, Inc. provides you with the finest liquid analytical

instrumentation available. If this is your first purchase from ECD, please read this manual before

installing and commissioning your new equipment.

If there are any questions concerning this equipment, please contact your local ECD representative, or

the factory directly at:

Electro-Chemical Devices, Inc.

1681 Kettering St.

Irvine, CA 92614 USA

Telephone: +1-949-336-6060

FAX: +1-949-336-6064

Website: www.ecdi.com

Email: [email protected]

© 2010 Electro-Chemical Devices, Inc. All rights reserved. No part of this manual may be used or reproduced in any form or by any means, or

stored in a database or retrieval system without prior written permission from Electro-Chemical Devices, Inc. Making copies of any part of this

manual for any purpose other than personal use is a violation of United States copyright laws. Document printed in the United States of

America.

HYDRA NO3--N Page iii

TABLE OF CONTENTS

PREFACE ........................................................................................................................................................ ii

TABLE OF CONTENTS .................................................................................................................................... iii

WARRANTY .................................................................................................................................................. vi

IMPORTANT SERVICE INFORMATION .......................................................................................................... vi

UNPACKING THE INSTRUMENT................................................................................................................... vii

1.0 GENERAL DESCRIPTION ........................................................................................................................... 1

1.0.0 Description ................................................................................................................................... 1

1.0.1 Chloride Ion Compensation ......................................................................................................... 1

1.0.2 Optional pH or Ammonium Measurement .................................................................................. 1

1.0.3 Temperature Compensation ........................................................................................................ 1

1.0.4 Cleaning and Maintenance .......................................................................................................... 1

1.1 FEATURES ............................................................................................................................................ 2

1.1.1 Features and Benefits .................................................................................................................. 2

1.2 Specifications ...................................................................................................................................... 2

1.2.1 Hydra Sensor ................................................................................................................................ 2

1.2.2 C22 Analyzer ................................................................................................................................ 3

1.3 Hydra Dimensional Drawing ............................................................................................................... 4

2.0 INSTALLATION ......................................................................................................................................... 5

2.1 UNPACKING ......................................................................................................................................... 5

2.2 ASSEMBLY ........................................................................................................................................... 5

2.2.1 Spray Cleaner ............................................................................................................................... 5

2.2.2 Immersion /Support Tube ............................................................................................................ 5

2.3 MOUNTING ......................................................................................................................................... 5

2.3.1 C-22 Analyzer ............................................................................................................................... 5

2.3.2 Hydra Sensor ................................................................................................................................ 6

2.4 WIRING ................................................................................................................................................ 6

2.4.1 Wiring, power .............................................................................................................................. 6

2.4.2 Wiring, Sensor .............................................................................................................................. 6

2.4.3 Wiring, 4-20 mA Outputs ............................................................................................................. 6

2.4.4 Wiring, Contact Relay Outputs ..................................................................................................... 7

Page iv HYDRA NO3--N

3.0 OPERATION ............................................................................................................................................. 8

3.1 KEYS ..................................................................................................................................................... 8

3.2 MENUS ................................................................................................................................................ 9

3.2.1 Nitrate Ion Channel 1 Menu Structure ........................................................................................ 9

3.2.2 Chloride Ion Channel 2 Menu Structure ...................................................................................... 9

3.2.3 pH or NH4+

Channel 3 Menu Structure ......................................................................................... 9

3.2.4 Graphical Display Screen ............................................................................................................ 10

3.2.5 Buffer Menu ............................................................................................................................... 10

3.2.6 Set-Up Menu .............................................................................................................................. 11

3.2.7 Status Menu ............................................................................................................................... 12

3.2.8 Configuration and Trim Menu.................................................................................................... 13

3.3 OUTPUTS ........................................................................................................................................... 13

3.3.1 Manual Mode (4-20 mA Hold Function) .................................................................................... 13

3.4.2 One AC10 with Two HYDRAs ...................................................................................................... 14

3.5 ION SELECTIVE FEATURES ................................................................................................................. 15

3.5.1 The Isopotential point ................................................................................................................ 15

3.5.2 Chloride Ion Interference Correction ......................................................................................... 16

4.0 START UP ............................................................................................................................................... 17

4.1 SET-UP AND CONFIGURATION .......................................................................................................... 17

4.1.1 Set Up Menus ............................................................................................................................. 17

4.1.2 Set Up Menu, MASTER/SLAVE ................................................................................................... 18

4.1.3 Configure and Trim Menu .......................................................................................................... 19

4.1.4 Configure and Trim Menu, MASTER/SLAVE ............................................................................... 20

4.2 CALIBRATION ..................................................................................................................................... 22

4.2.1 Recommended Materials ........................................................................................................... 22

4.2.2 Temperature Calibration ............................................................................................................ 23

4.2.3 Single point Calibration .............................................................................................................. 23

4.2.4 Two point Calibration ................................................................................................................. 24

4.2.5 Chloride Ion Compensation ....................................................................................................... 24

5.0 MAINTENANCE ...................................................................................................................................... 25

5.1 MAINTENANCE SCHEDULE ................................................................................................................ 25

5.2 CLEANING THE SENSOR ..................................................................................................................... 25

HYDRA NO3--N Page v

5.3 REPLACING THE ELECTRODES ........................................................................................................... 25

6.0 TROUBLESHOOTING .............................................................................................................................. 26

7.0 ENGINEERING DOCUMENTATION ......................................................................................................... 27

7.1 SPECIFICATIONS ................................................................................................................................ 27

7.2 OUTLINE & DIMENSIONAL DRAWING ............................................................................................... 28

7.2.1 Hydra Sensor Dimensions .......................................................................................................... 28

7.2.2 C-22 Dimensions ........................................................................................................................ 28

7.2.3 Sun Shield ................................................................................................................................... 29

7.3 WIRING DIAGRAM ............................................................................................................................. 30

7.3.1 Sensor Color Coded Diagram ..................................................................................................... 30

7.3.2 Instrument – Terminal Layout/Connections .............................................................................. 30

8.0 ORDERING INFORMATION .................................................................................................................... 31

8.1 PART NUMBERS/MODEL NUMBERS ................................................................................................. 31

8.2 ACCESSORIES ..................................................................................................................................... 31

8.3 SPARE PARTS ..................................................................................................................................... 32

Page vi HYDRA NO3--N

WARRANTY Electro-Chemical Devices, Inc. (ECD) warrants all products it manufactures to be free from defect in materials and factory

workmanship, and agrees to repair or replace any product that fails to perform, as specified, within one (1) year after date of

shipment. This warranty shall not apply to any product that has been:

1. Subjected to misuse, negligence or accident;

2. Connected, installed, adjusted or otherwise used not in accordance with the instructions furnished by ECD;

3. Repaired, modified or altered by persons not authorized by ECD, resulting in injury to the performance, stability or

reliability of the product.

This warranty is in lieu of any other warranty, expressed or implied. ECD reserves the right to make changes in the design or

construction of its products at any time, without prior notification, and without incurring any obligation to make any changes in

previously delivered products.

Seller’s sole liabilities and the buyer’s sole remedies under this agreement shall be limited to a refund in the purchase price, or

at ECD’s discretion, to the repair or replacement of any product that proves, upon ECD’s examination, to be defective, when

returned to the factory, transportation prepaid by the buyer, within one (1) year of the product’s original shipment date. Seller

shall not be liable for damages consequential or incidental to defects in any product, for failure of delivery in whole or in part,

for injuries resulting from its use, or for any other cause.

This warranty and the writing attached constitute the full understanding of seller and the buyer, and no terms, conditions,

understanding, or agreement purporting to modify or vary the terms hereof shall be binding unless hereafter made in writing

and signed by an authorized official of Electro-Chemical Devices, Inc.

This warranty does not cover pH, ORP or Specific Ion measurement, reference or combination electrodes or electrode

cartridges that have been commissioned in service.

IMPORTANT SERVICE INFORMATION Use only factory authorized components for repair. Tampering or unauthorized substitution of components may

adversely affect the operation of this product and may void the warranty.

If service or repair is required, please obtain the serial number(s) or sales order number of the product(s) in

question and contact ECD’s Service Department at:

+1-800-729-1333 (USA/Canada) or +1-949-336-6060

or email [email protected]

A Return Material Authorization (RMA) number must be obtained from the service department before returning

any material to ECD. All material returned to ECD shall be shipped prepaid to the factory.

HYDRA NO3--N Page vii

UNPACKING THE INSTRUMENT

Your Electro-Chemical Devices instrument has been carefully packaged to protect it from damage during

shipment and dry storage. Upon receipt please follow the procedure outlined below.

1. Before unpacking, inspect the condition of the shipping container to verify proper handling by

the carrier. If damage is noted, save the shipping container as proof of mishandling for the

carrier.

2. Check the contents of the shipping container with the items and quantities shown on the

packing list. Immediately report any discrepancies to ECD.

3. Save the original packing material until you are satisfied with the contents. In the event the

product(s) must be returned to ECD, the packing material will allow you to properly ship it to

ECD.

4. Familiarize yourself with the instrument before installation, and follow proper installation and

wiring procedures.

HYDRA NO3--N Page 1

1.0 GENERAL DESCRIPTION

1.0.0 Description

The HYDRA Nitrate Analyzer measures the

concentration of dissolved nitrate ion as nitrogen

(NO3--N) in water. The sensor uses two electrodes

to determine the NO3--N concentration, a Nitrate

Ion Electrode and a Chloride Ion Electrode. An

optional pH or Ammonium electrode is available

for additional process information. It is designed

for use in all kinds of water. Typical applications

include monitoring environmental waters, lakes,

streams and wells as well as wastewater treatment in aeration basins, sludge digesters and effluent.

1.0.1 Chloride Ion Compensation

The Nitrate Ion Electrode provides the primary measurement. Any Chloride ion in the sample, due to its

similar size and charge to the Nitrate ion, causes a positive interference in the measurement. The

Chloride Ion Electrode measures the amount of chloride ion present in the sample and HYDRA C22

Analyzer subtracts the appropriate amount of signal from the Nitrate Measurement.

1.0.2 Optional pH or Ammonium Measurement

An optional pH or ammonium electrode is available in the HYDRA-NO3 sensor providing additional

information about the process solution. The HYDRA-C22 Analyzer provides an additional 4-20 mA output

to transmit this information.

1.0.3 Temperature Compensation

Temperature is also measured and used to compensate each of the three electrode measurements.

While the pH electrode response is well defined with respect to temperature the ion electrodes tend to

be less well behaved. For the best results calibrate the sensors near the process temperature.

1.0.4 Cleaning and Maintenance

The HYDRA Nitrate Analyzer is configured to periodically actuate a cleaning cycle using the integral spray

cleaner in the sensor. The period and duration of the cleaning cycle is user configurable. The 4-20 mA

output is held at either the last value or a preset value during the cleaning. This minimizes the formation

biofilms or other coatings on the electrodes keeping maintenance to a minimum.

The rugged HYDRA sensor has a 1 ¼” NPT rear facing thread for attaching an extension/immersion tube

for easy installation from catwalks or handrails. The HYDRA sensor is submersible with an IP68 degree of

ingress protection. A removable electrode guard facilitates easy electrode replacement when necessary.

The HYDRA sensor features internal signal conditioning that allows the sensor to be mounted up to 200

meters from the analyzer.

Page 2 HYDRA NO3--N

1.1 FEATURES

1.1.1 Features and Benefits

• Separate, economical, easily replaceable Nitrate, Chloride and optional pH electrodes

• Fast and Accurate Nitrate Measurement NO3- or NO3

--N

• Automatic compensation for Cl- interference

• Temperature compensated NO3--N measurement

• Rugged PVC design with removable electrode guard for easy maintenance

• Integral Spray Head Cleaner

� Cleans sensor in situ with turbulence caused by pressurized air

• Internal Signal Conditioning allows up to 200 meters between Sensor and Analyzer

1.2 Specifications

1.2.1 Hydra Sensor

• Three Electrode System with spray cleaner

• Nitrate ISE (NO3--N) is the primary measurement

• Chloride ISE is used for compensation of the NO3- signal.

• Optional pH or NH4+ electrode

• The Sensor is waterproof with an ingress rating of IP 68.

Measurement Range

• NO3--N: 0.1 to 1000 ppm

• Cl-: 0.1 to 10,000 ppm

• pH: 2-12 pH

• NH4+: 0.1 to 1000 ppm

Operating Temperature

• 0° C to 40° C (32° F to 104° F)

Min/Max Flow Rate by the sensor

• Minimum 0.1 m/s

• Maximum 3.0 m/s

Wetted Materials

• PVC, PES, PVDF, PTFE, Viton, Glass, 316 SS

Accuracy

• ± 3% of reading, dependent on Calibration

Response Time

• T90 approximately 1 minute

HYDRA NO3--N Page 3

Electrode Life

• ISEs: 4- 6 months, typical

• pH electrode: 6-12 months, typical

1.2.2 C22 Analyzer

Measurements

• Nitrate: 0.1 ppb to 1000 ppm as NO3-- N

• Chloride: 0.1 ppm to 1000 ppm

• pH: 0 to 14 pH or NH4+: 0.1 to 1000 ppm

• Temperature: 0° C to 100° C (32° F to 212° F)

Compensation

• Chloride: 0.1 to 1000 ppm

• Temperature: 0° - 50°C

Display

• 2.5” X 1.75” backlit LCD

• 4 lines of Text

• Graphical display, NO3-- N vs. Time

Enclosure

• NEMA 4X, LxWxD: 5.7” x 5.7” x 7”

Outputs

• (2) 4-20 mA maximum load 800 ohms @ 24 VDC

• mA #1: 0.1 to 50 mg/l NO3-- N (User Configurable)

• mA #2 (Optional): 2 - 12 pH or 0.1 to 50 mg/l NH4+ (User Configurable)

• Optionally up to (4) 4-20 mA outputs*

Page 4 HYDRA NO3--N

Input Power

• 110/220 VAC @ 50/60 Hz

Alarm Relay Ratings

• SPDT 230 VAC/5A or 30 VDC/5A resistive max. All are configured as Normally Open (NO).

Relay Standard Configuration Master Configuration Slave Configuration

1 Spray Cleaner NH4-N Alarm NH4-N Alarm

2 NH4-N Alarm (PV 1) Digital Input to Slave pH Alarm

3 Spray Cleaner

4 Diverter Valve

1.3 Hydra Dimensional Drawing

Figure 1.3

1.3.1 Parts List:

o HYDRA Sensor with Electrodes, Calibration Cap,

o 30’ of ¼” air tubing, Electrode Removal Tool

HYDRA NO3--N Page 5

2.0 INSTALLATION

2.1 UNPACKING

Carefully remove the HYDRA sensor from its shipping container. Inspect the sensor for damage. Verify

the electrodes, Nitrate, Chloride, (optional pH or NH4+) and the Spray Cleaner Nozzle are installed in the

sensor housing. The electrodes should be hand tightened into place so that the sealing o-rings are not

visible. The electrodes are supplied with protective caps that must be removed before start up. Do not

remove the caps until ready to use.

### NEVER SUPPORT THE HYDRA SENSOR BY THE CABLE, IRREPAIRABLE DAMAGE WILL OCCUR ###

2.2 ASSEMBLY

The HYDRA Sensor is shipped completely assembled, before use it must be connected to the analyzer

and an air supply. Connect the spray cleaner feed tube to a compressed air supply controlled by a

solenoid valve (not supplied). Attach an immersion/support tube (not supplied). Finally connect the

sensor wires and 110 VAC power to the analyzer as shown on the wiring diagram. Connect the Cleaner

Relay to the solenoid and connect the 4-20 mA Output(s) and Alarm Relay to the Control System, (PLC or

DCS). The HYDRA is now ready to use.

2.2.1 Spray Cleaner

The Spray Cleaner uses compressed air to create turbulence around the electrodes which removes dirt

and films from the measurement surfaces. Depending on the process being measured the cleaner

should be actuated for 15-30 seconds every 0.25 -2 hour period. The spray cleaner connection is a ¼”

compression fitting and requires between 25-75 psi air pressure. The air supply is controlled with a user

supplied solenoid valve through Relay 1 in the C-22 analyzer. The solenoid valve should be a 110 AC

powered, <10 watt device. Wire the solenoid to Relay 1 as described in Section 2.4.4 below.

### NEVER SUPPORT THE HYDRA SENSOR BY THE CABLE, IRREPAIRABLE DAMAGE WILL OCCUR ###

2.2.2 Immersion /Support Tube

Feed the cable and compressed air line through the immersion/support tube (not supplied). Connect a

support tube to the 1 ¼” MNPT thread at the rear of the sensor. The Hydra sensor weighs approximately

5.3 lbs. The support tube must be able to support the weight of the HYDRA sensor in the user’s

installation, whether vertical or angled. The recommended material for the immersion tube is 1.5”

Schedule 80 PVC pipe with a reducer fitting to 1 ¼” FNPT.

2.3 MOUNTING

2.3.1 C-22 Analyzer

Mount the C-22 in a location where there is easy access to the analyzer and sensors. Install the system

in an area where vibrations, electromagnetic and radio frequency interference are minimized or absent.

Do not mount in direct sunlight or areas of extreme heat (temperature > 120°F). The NEMA 4X C-22 is

suitable for outdoor use but it is best to mount it with a protective cover or sunshield, PN 1000260-1

with vertical pole mounting hardware or 1000260-2 for horizontal rail mounting hardware.

Page 6 HYDRA NO3--N

There are three basic installation methods for the C-22, Wall Mount (UM), Panel Mount (PM) and Pipe

Mount (HM). The Pipe Mounting hardware includes 2” “U” bolts for attaching to standard 2” handrails.

(See the installation drawings in Section 9.3 at the rear of the manual)

2.3.2 Hydra Sensor

Install the sensor where the measured sample is representative of the entire process. Although the

sensor will function in a quiescent sample, flow improves the measurement. The recommended

minimum flow is 0.1 m/sec.

Securely mount the HYDRA sensor with the measuring end at least 6”away from the tank wall and

bottom. Ensure that the sensor is immersed at least 6” at all times.

Use care when servicing the sensor to ensure that the sensor does not hit the tank wall or bottom which

could break the sensing electrodes.

2.4 WIRING

Electrical wiring should only be conducted by qualified personnel. See the wiring color code for the

Hydra Sensor and the C-22 wiring diagram in Section 7.3 below.

2.4.1 Wiring, power

Attach power cable as shown in the diagram in Section 7.3 or the inside of the C22 cover. Feed the cable

through the gland fitting on the right hand side of the C-22. Tighten the cable gland to provide a good

seal to the cable. The instrument can be powered up at this point with no harm to the analyzer but it is

best to wait until the sensors are installed.

2.4.2 Wiring, Sensor

Attach the sensor wires as described on the diagram inside the C22 cover. Feed the sensor cable

through the gland fitting on the left hand side of the C-22. Do not use the same gland fitting for the AC

power or Alarm/Relays. The green terminal strip connectors are detachable from the circuit boards.

Remove the connector by pulling straight back from the circuit board.

2.4.3 Wiring, 4-20 mA Outputs

The 4-20 mA output is an unpowered output, 24V must be supplied from an external source, the PLC or

DCS receiving the signal or from the internal PS2 power supply.

If the internal PS2 Power Supply is used, first connect a jumper wire between Terminal #1 (RTN) on the

PS2 Power Supply Board and Terminal #2 of the 4-20 mA 1 output connector, the two slot connector on

the top of the Channel 2 input card. (See diagram in Section 7.3) Then connect a shielded 22 gauge

twisted pair communication cable to Terminal #2 (+24V) on the PS2 power supply board and Terminal

#1 of the 4-20 mA 1 connector.

If a second mA output is supplied connect it in the same manner, jumper Terminal #1 of the PS2 board

to Terminal #2 of the 4-20 mA 2 output terminal strip then connect the two wire communication cable

to PS2 Terminal #2 and mA 2 Terminal #1.

HYDRA NO3--N Page 7

If the 4-20 mA loop is powered from an external source then simply connect a shielded 22 gauge twisted

pair communication wire to Terminals #1 and #2 of the 4-20 mA terminal on the Channel 2 input card.

The standard Hydra C-22 is configured with the NO3--N on mA 1 and pH on mA 2.

2.4.4 Wiring, Contact Relay Outputs

The standard configuration has two SPDT 230V 5 A relays that can be wired either normally open (NO)

or normally closed (NC). The default configuration is set to use the relays as normally open. Relay 1

actuates the solenoid for the air blast spray cleaner and Relay 2 is an NO3--N alarm relay, either a High or

Low Alarm.

Relay 1

Connect the Line terminal of the 110VAC power to the C (common) terminal of Relay 1. Connect the

Cleaner solenoid wires to the neutral terminal of the 110 VAC power and the NO (normally open)

terminal of Relay 1. (See Section 7.3)

Relay 2

Wire Relay 2 as a NO relay. Relay 2 is an alarm relay and should be connected to the Control System or

an external alarm.

Do not run the cable through the same cable gland fitting as the electrodes or the 4-20 mA signals.

The MASTER configuration has (4) SPDT 230V 5 A relays that are wired as normally open (NO) relays.

Relay 1

Wire Relay 1 as a NO relay. Relay 1 is an alarm relay and should be connected to the Control System or

an external alarm.


Relays 2 (NO) to Slave Analyzer, Aux In Terminals

Relay 3 (NO) to AC10 Air Blast Spray Cleaner, Compressor terminals

Relay 4 (NO) to AC10 Air Blast Spray Cleaner, Diverter terminals

The SLAVE configuration has (2) SPDT 230V 5 A relays that are wired as normally open (NO) relays.

Relays 1, 2

Wire Relays 1 and 2 as a NO relays. Relays 1 and 2 are alarm relays and should be connected to the

Control System or an external alarm.


Page 8 HYDRA NO3--N

3.0 OPERATION

This section will provide a basic overview of the C22 Analyzer/Controller. It covers the basic Menu

structure, the function of the MENU SELECT keys and the CALIBRATE keys.

The C-22 HYDRA analyzer has three measurement channels:

Channel 1, Nitrate as Nitrogen, NO3--N,

Channel 2, Chloride, Cl- and

Channel 3, (optional) pH or NH4+

3.1 KEYS

The blinking cursor indicates the active point where menus can be selected or numerical values

adjusted. There are two sets of keys on the C22 analyzer, the MENU SELECT keys and the CALIBRATE

keys.

The MENU SELECT keys are used to move the cursor vertically changing the displayed menu. These keys

are also used to Save/Accept the calibration data and exit the calibration menu.

The CALIBRATE keys are used to enter menus, change numerical values and move the cursor

horizontally.

To enter a calibration menu or parameter adjustment line simultaneously press both of the

Horizontal CALIBRATE keys, ◄CALIBRATE►

Pressing either of the Horizontal CALIBRATE keys separately will move the cursor horizontally to the

point under the digit to be adjusted. The Vertical CALIBRATE keys are used to adjust numeric values.

Pressing the upper key will increase the value and pressing the lower key will decrease the value. When

HYDRA NO3--N Page 9

the cursor is on a menu line, not in the menu, pressing the down CALIBRATE key will return the cursor to

the HOME Screen from any menu.

3.2 MENUS

There are three sets of menus on the Model C-22. The Channel 1 menus (PV1) the Nitrate Ion channel

(NO3--N), the Channel 2 menus (PV2) the Chloride Ion channel and the Channel 3 menus (PV3) the pH or

NH4+ channel. Pressing the MENU SELECT UP key will first access the Chloride channel and then the pH

channel, pressing the MENU SELECT DOWN key will access the Nitrate channel. Follow the guide below

for the general menu structure.

3.2.1 Nitrate Ion Channel 1 Menu Structure

Screen Displayed Button Pressed

Home Screen MENU SELECT ▼

Graphical display MENU SELECT ▼

Parameter Selection Screen (Ch 1 Buffer) MENU SELECT ▼

Parameter Selection Screen (Ch 1 Set-Up) MENU SELECT ▼

Parameter Selection Screen (Ch 1 Status) MENU SELECT ▼

Configure/ Trim Menu MENU SELECT ▲..... To return to the Home screen

3.2.2 Chloride Ion Channel 2 Menu Structure


Home Screen MENU SELECT ▲

pH Manual Mode Screen MENU SELECT ▲

Parameter Selection Screen (Ch 2 Status) MENU SELECT ▲

Parameter Selection Screen (Ch 2 Set-Up) MENU SELECT ▲

Parameter Selection Screen (Ch 2 Buffer) MENU SELECT ▲

To channel 3 MENU SELECT ▼….. To return to the Home screen

3.2.3 pH or NH4+

Channel 3 Menu Structure



Parameter Selection Screen (Ch 3 Status) MENU SELECT ▲

Parameter Selection Screen (Ch 3 Set-Up) MENU SELECT ▲


Contrast (adjustment screen) MENU SELECT ▼….. To return to the Home screen

Page 10 HYDRA NO3--N

3.2.4 Graphical Display Screen

This Graphical Display is only available in the Channel 1 menu. It is located one screen down from the

Home Screen. It displays a user assigned output value, for example, 4-20 mA1 vs. time. The Graphical

Display variables of; which Output is displayed and what Time interval is used is configured in the

Channel 1 Set-Up Menu. See Section 3.2.6, below, for more information on the Set-Up Menu.

3.2.5 Buffer Menu

The Buffer Menus are Calibration Menus. To access the Buffer Menu the cursor must be flashing in front

of the “Ch X Buffer” line. Simultaneously press both of the Horizontal CALIBRATE keys to enter the

Calibration screens. The calibration is structured for a two point calibration.

The first calibration “1 NO3-N” is the “zero point” calibration. This sets a base millivolt value to a specific

ion concentration. The concentration is adjustable to suit the measurement range, see procedure

below. When adjusting a value first move the cursor to the largest integer to be adjusted, perform the

adjustment and then move to the next lower value. When a calibration is performed the Cal line will

display the millivolt value associated with calibration standard solution. The Cal value can be reset to 0

millivolts by “entering” the Cal line.

The second calibration screen is the “slope, mV/ppm” calibration. This calibration should use a standard

solution that is at least 10X the concentration of the solution used in the first calibration. Scroll down to

the “2 NO3-N” line and enter the value of the standard solution and the Cal line will display the new

slope, mV/ppm. Follow the same procedure for calibration of Channels 2 & 3.


Ch1 Buffer

◄ CALIBRATE ► (enter the calibration menu by pressing

both ◄► simultaneously)

1 NO3-N 4.00 ppm

Cal .0 mV

◄ CALIBRATE ►(enter line, zero pt. Cal 1)

Sensor should be in the Cal 1 solution. (example 5 ppm)

1 NO3-N 4.00 ppm

Cal 393.5 mV

To set Calibration Sol. Value use the CALIBRATE ◄ or ► to

move cursor. Use the ▲or▼ to adjust the integer value.

1 NO3-N 5.00 ppm

Cal 393.5 mV

Wait for reading to stabilize….

MENU SELECT ▼ (accept Calibration)

1 NO3-N 5.00 ppm

Cal 393.5 mV

MENU SELECT ▼ (move to Cal line)

1 NO3-N 5.00 ppm

Cal 393.5 mV

MENU SELECT ▼(move to Cal 2, Slope)

Remove sensor, rinse and place in Cal 2 solution

2 NO3-N 00.0 ppm

Cal 29.6 mV/dec

◄ CALIBRATE ► (enter screen)

2 NO3-N 00.0 ppm

Cal 29.6 mV/dec

To set Calibration Sol. Value use the CALIBRATE ◄ or ► to

move cursor. Use the ▲or▼ to adjust the integer value.

2 NO3-N 50.0 ppm

Cal 29.6 mV/dec

Wait for reading to stabilize….

MENU SELECT ▼ (accept Calibration)

2 NO3-N 50.0 ppm

Cal 29.2 mV/dec

CALIBRATE ▼ (return to Home Screen)

HYDRA NO3--N Page 11

3.2.6 Set-Up Menu

The Setup menu allows the various parameters to be configured for the user’s requirements. Each

Channel has a Set-Up Menu that includes the parameters associated with that specific Channel. The

Graphical Display, 4-20 mA Outputs, Alarm Relays and Timers are all configured in the Setup Menu. Ion

selective electrodes have unique Iso-Potential points, the mV value/ concentration point where changes

in temperature have no effect. This value is supplied with each specific ion electrode and must be

entered in the “isopot” entry line below. This provides the analyzer with the base point for temperature

compensation.


Ch1 Setup ◄ CALIBRATE ► (enter the screen)

Plot 4-20 1

Sample .1 m

MENU SELECT ▼

(the “4-20 1” indicates the displayed value, variable)

Plot 4-20 1

Sample .1 m

MENU SELECT ▼

(the Sample time is 0.1 minutes, variable)

4mA1 .0 ppt OUTPUT SET-UP

20mA1 999.9 ppt

◄ CALIBRATE ► (enter 4mA line)

4mA1 .0 ppt

20mA1 999.9 ppt

To adjust the value use the CALIBRATE ◄ or ► to move

cursor. Use the ▲or▼ to adjust the integer value.

4mA1 00.1 ppb

20mA1 999.9 ppt

MENU SELECT ▼ (accept the Value)

4mA1 00.1 ppb

20mA1 999.9 ppt

MENU SELECT ▼

4mA1 00.1 ppb

20mA1 999.9 ppt

◄ CALIBRATE ► (enter 20mA line)

4mA1 00.1 ppb

20mA1 999.9 ppt



4mA1 00.1 ppb

20mA1 100 ppm


4mA1 00.1 ppb

20mA1 100 ppm

MENU SELECT ▼

(4-20 is now set to 0.100 ppb to 100 ppm)

2 On > .0 ppt RELAY SET-UP

2 Off < .0 ppt

◄ CALIBRATE ► (enter Relay Set Point)

2 On > .0 ppt

2 Off < .0 ppt



2 On > 10.00 ppm

2 Off < .0 ppt


2 On > 100.0 ppm

2 Off < .0 ppt

MENU SELECT ▼

2 On > 10.00 ppm

2 Off < .0 ppt

◄ CALIBRATE ► (enter Relay Hysteresis Point)

2 On > 10.00 ppm

2 Off < .0 ppt



2 On < 10.00 ppm

2 Off > 11.00 ppm

MENU SELECT ▼ (accept the Value) ** Whether the relay is

a High or Low Alarm is determined by the Off value **


2 On < 10.00 ppm (Low Alarm

2 Off > 11.00 ppm example)

2 On > 10.00 ppm (High Alarm

2 Off < 9.500 ppm example)

MENU SELECT ▼(If the NO3--N drops below 10.0 ppm the

contact closes until it is higher than 11 ppm. If the Off value

is set to 9.5 ppm then the contact will switch to a High

Alarm, closing at 10.0 ppm and re-opening below 9.5 ppm.)

Timer 1: periodic

←Clock

◄ CALIBRATE ►

Per 0d00 :00 :00 Cleaning Timer

Now 0 00 :00 :00 (Per sets the time

On 0 00 :00 :00 between cleaning

Off 0 00 :00 :00 cycles)

◄ CALIBRATE ►

(Set the Period to 1 hour then every hour the Now Clock

will reset to 0:00:00 and trigger the On Timer which is set at

0:00:00, starting the cleaning cycle.)

Per 0d00 :00 :00

Now 0 00 :00 :00

On 0 00 :00 :00

Off 0 00 :00 :00


cursor. Use the ▲or▼ to adjust the integer value, 30 min

then MENU SELECT ▼ (accept the Value)

MENU SELECT ▼, MENU SELECT ▼, MENU SELECT ▼

Per 0d00 :30 :00

Now 0 00 :00 :00 (Set the Off time

On 0 00 :00 :00 at 30 seconds)

Off 0 00 :00 :30

◄ CALIBRATE ► (enter the Off line, the duration of the

cleaning cycle) To adjust the value use the CALIBRATE ◄ or

► to move cursor. Use the ▲or▼ to adjust the integer

value, then MENU SELECT ▼ (accept the Value)

Timer 2: oneshot↑

←timer 1←clock

◄ CALIBRATE ►

4-20 mA hold time after cleaning cycle, (CT + 1 minute)

Now 0 00 :00 :00 Manual Mode Timer

On 0 00 :00 :00 (Hold Function)

Off 0 00 :01 :30 (Set at 1 min 30 sec)

MENU SELECT ▼, MENU SELECT ▼, ◄ CALIBRATE ►



Cl coef .004

Cl comp Off

MENU SELECT ▼ NO3 electrode selectivity ratio for Cl-

(NO3 ppm) – 0.004(Cl- ppm) = NO3 –N concentration

Cl coef .004

Cl comp Off

MENU SELECT ▼ Cl- compensation should be Off for

Calibration and On for Measurement

TC .333 %/°C

Isopot 20.0 mV

MENU SELECT ▼ Temperature Compensation (no adjustments needed)

TC .333 %/°C

Isopot .0 mV ** Mandatory **

◄ CALIBRATE ► (Enter Iso-Potential Entry line)

**Iso-Potential value supplied with each electrode**

TC .333 %/°C

Isopot 20.0 mV



TC .333 %/°C

Isopot 187.0 mV


MENU SELECT ▼

Noise Filter 5 CALIBRATE ▼ (return to Home Screen)

3.2.7 Status Menu

The Status menu displays the actual uncompensated millivolt value from the sensor, very handy

information for troubleshooting. The day and time, hours: minutes: seconds, are also displayed.


Ch1 Status ◄ CALIBRATE ► (enter screen)

Fri 09:11:28 MENU SELECT ▼

Input 364.2 mV CALIBRATE ▼ (return to Home Screen)


3.2.8 Configuration and Trim Menu

The Configure/Trim menu provides access to the menus used to assign parameters, define functions and

trim input and output signals. This group of menus should rarely be needed as the instrument was

configured at the factory before testing and shipment. The basic structure is as follows. See the “System

22 Configuration Manual” for details about these menus, available at www.ecdi.com.


Configure/Trim ◄ CALIBRATE ► (enter screen)

Passwords MENU SELECT ▼(allows menus to be password protected)

Default Display MENU SELECT ▼(defines Home Screen)

4-20 assign MENU SELECT ▼(Assigns parameter/function to mA output)

Manual Mode MENU SELECT ▼(Allows manual control of mA outputs)

Relay assign/Test MENU SELECT ▼(Assigns triggering parameter to a relay)

PID Assign MENU SELECT ▼(Assigns PID to a PV)

PWM Assign MENU SELECT ▼(Assigns Pulse Width Modulation to a PV)

Clock and timers MENU SELECT ▼(Sets Clock function, assigns Timers)

Logic Gates MENU SELECT ▼(assigns AND/OR gates)

Ion Species MENU SELECT ▼(Sets Ion Measured)

General MENU SELECT ▼( Not Used)

°C/°F & Temp Cal MENU SELECT ▼( allows temperature trim/cal, choose °C/°F)

4-20 Trim/Test MENU SELECT ▼(allows mA trim)

Millivolt Trim CALIBRATE ▼ (return to Home Screen)

3.3 OUTPUTS

The Standard C-22 HYDRA Analyzer has two 4-20 mA outputs. The default configuration has “mA 1”

configured for NO3-N, 4-20 mA = .100 ppb to 50 ppm and “mA 2” is configured for pH, 4-20 mA = 2-12

pH. To reconfigure the outputs see Section 3.2.6, Set-Up Menu, above.

The Outputs, mA 1 and mA 2, are held at the “Last Value” by Timer 2 during the Air Blast Cleaning Cycle.

The Outputs return to live readings one minute after the cleaning cycle ends. Timer 2 is a “one-shot”

timer triggered by Timer 1. When Timer 1 triggers, it starts Timer 2 which is set to run for a period of

time equal to the cleaning time plus one minute.

3.3.1 Manual Mode (4-20 mA Hold Function)

The % Output is displayed on the Home Screen for the NO3-N output, mA 1, and one screen above the

Home Screen for the pH % Output, mA 2.

The outputs can be set for manual control by simultaneously pressing both horizontal CALIBRATE keys

when the cursor is in front of the % Output line. An “M” will be displayed in front of the % Output value.


The Output will remain frozen at the last value until the Manual Mode is turned off. The Manual Mode

hold function is commonly used to freeze the outputs during maintenance and calibration cycles. While

in Manual Mode the Output can be adjusted between 0 and 99.9% using the CALIBRATE keys, very

useful for troubleshooting loop communication problems.

To exit Manual Mode press the left CALIBRATE arrow, ◄, three times and the “M” will disappear, the

Output will return to a live reading.

3.4 CONTACTS-Alarm Relays

3.4.1 Standard Configuration

Relay 1 is configured to control the Air Blast Spray Cleaner. It is triggered by Timer 1. Timer 1 is

configured as a periodic timer. The default setting for the period is 15 minutes with the duration set at

30 seconds. The period and duration of the cleaning cycle is user configurable and dependent on the

application. For water going to the clarifier an adequate cleaning cycle may be, every two hours for 15

seconds, where incoming water to an aeration basin may require a 30 second cleaning cycle every 15

minutes.

The Now clock is an arbitrary timer. The Period determines the amount of time that must pass before

the Now clock resets to 00 hours, 00 minutes and 00 seconds, 00: 00: 00. The On time is the start time

and it is set at 00: 00: 00, so every time the clock resets Relay 1 is triggered. The Off time sets the

duration of Timer 1 and is set at 00: 00: 30, thirty seconds. (See Section 3.2.6 above)

To Change how often the Spray Cleaner actuates, change the Per line to the desired period. The display

is set for days, hours: minutes: seconds, 0d00: 00: 00.

To Change the duration of the Cleaning cycle change the Off line. If the duration is changed from the

default value of 30 seconds then the Manual Mode Timer should be adjusted to allow the sensor to

stabilize after the cleaning cycle. Adjust Timer 2; Off line; to the new Clean Time (CT) + 1 minute.

Relay 2 is configured as a high alarm triggering at 10.0 ppm NH4+-N. The value can be changed in the Set-

Up Menu as shown in Section 3.2.6. Changing the > sign to a < sign in the On line changes the set point

from a high to a low alarm. This can also be accomplished by setting the Off value higher than the On

value which forces an automatic sign change. The Off value is the hysteresis point that the PV has to

correct to before the relay disengages.

3.4.2 One AC10 with Two HYDRAs

When two HYDRA Analyzers are connected to one AC10 Air Blast Spray Cleaning System then one C22

Analyzer becomes the MASTER and the other C22 Analyzer is a SLAVE.

3.4.2.1 Master Configuration

Relay 1 is configured as a high alarm triggering at 10.0 ppm NO3-N. The value can be changed in the Set-

Up Menu as shown in Section 3.2.6. Changing the > sign to a < sign in the On line changes the set point

from a high to a low alarm. This can also be accomplished by setting the Off value higher than the On


value which forces an automatic sign change. The Off value is the hysteresis point that the PV has to

correct to before the relay disengages.

Relay 2 is configured to trigger the Digital Input (Aux In) of the SLAVE analyzer. This initiates the Manual

Mode function of the SLAVE analyzer, placing the mA outputs in a Last Value Hold (Bumpless).

Relay 3 is configured to control the Air Blast Spray Cleaner. It is triggered by Timer 1. Timer 1 is

configured as a periodic timer. The default setting (Set Up Menu) for the period is 15 minutes with the

duration set at 30 seconds. This triggers a cleaning cycle every 15 minutes alternating between the

MASTER and the SLAVE units, so each HYDRA sensor is cleaned every 30 minutes. (see Relay 4

below)The period and duration of the cleaning cycle is user configurable and dependent on the

application. For water going to the clarifier an adequate cleaning cycle may be, every two hours for 15

seconds, where incoming water to an aeration basin may require a 30 second cleaning cycle every 15

minutes.

The Now clock is an arbitrary timer. The Period determines the amount of time that must pass before

the Now clock resets to 00 hours, 00 minutes and 00 seconds, 00: 00: 00. The On time is the start time

and it is set at 00: 00: 00, so every time the clock resets Relay 1 is triggered. The Off time sets the

duration of Timer 1 and is set at 00: 00: 30, thirty seconds. (See Section 3.2.6 above)

To Change how often the Spray Cleaner actuates, change the Per line to ½ the desired period. The

display is set for days, hours: minutes: seconds, 0d00: 00: 00.

To Change the duration of the Cleaning cycle change the Off line. If the duration is changed from the

default value of 30 seconds then the Manual Mode Timer should be adjusted to allow the sensor to

stabilize after the cleaning cycle. Adjust Timer 2; Off line; to the new Clean Time (CT) + 1 minute.

Relay 4 is configured to control the diverter valve which alternates the Air Blast between the two

sensors. It is triggered by Timer 2. Timer 2 is configured as a periodic timer. The default setting (Set Up

Menu) for the period is 30 minutes with the duration set at 30 seconds. The Period of Timer 2 must be

twice the Period of Timer 1 and have the same duration.

3.5 ION SELECTIVE FEATURES

The Hydra C22 analyzer has several features unique to Ion Selective Electrode measurements,

Isopotential and Interfering Ion Correction. The measurement range of the sensors is from some ppb

level to some ppm level, XXX ppb – XXX ppm, not the traditional 0 – XXX common to most

measurements, there is no zero value. This is most evident when configuring the 4-20 mA outputs.

3.5.1 The Isopotential point

Isopot in the menu is the mV value of the specific sensor where changes in the temperature of the

solution do not change the output of the sensor. This is the base point for temperature compensation

correction. Most pH electrodes have an isopotential near pH 7, but each type of Ion Selective electrode

has a unique isopotential value. Each NO3- and Cl- electrode is supplied with an Isopot that must be

entered in the respective Set-Up Menu.


3.5.2 Chloride Ion Interference Correction

Chloride ions and Nitrate ions have a similar ionic size and the same electrical charge. If Chloride ions are

present in the measured solution then they will cause a positive Interference on the Nitrate Ion

Measurement. The corrections for the Interfering Ions are in the Cl coef and Cl comp screen in the Set-

Up menu. The Cl coef, Chloride ion selectivity, is the correction factor, ppm NO3-/ppm Cl

-;

Example: (250 ppm Cl-) x (0.010 ppm NO3

-/ ppm Cl

-) = 2.5 ppm NO3

-

With the Cl coef set at 0.010 (100 Cl-/ NO3

-) then 50 ppm Chloride ion would cause the Nitrate

measurement to read 0.5 ppm high. When the Cl comp line is On the C22 Analyzer uses the Chloride ion

concentration from the Chloride Ion Electrode and the Cl coef factor to calculate the amount of

interference on the Nitrate Ion Electrode and subtracts it from the measured nitrate value before

displaying the NO3-N value.


4.0 START UP

The HYDRA Analyzer and Sensor was assembled and tested at the factory before shipment. The sensor

was then disconnected from the analyzer, cleaned and packaged for shipment. The HYDRA C22 analyzer

is configured as shown below and should be ready to use aside from any changes the user may wish to

make to the Outputs, Cleaning Timers and Alarm Set points.

Complete all of the steps in Section 2 INSTALLATION (above) before proceeding further. These steps

include:

1. Install the Analyzer in a suitable environment.

2. Determine an installation method and representative sample point for the sensor.

3. Connect the Air Blast Spray Cleaner tube to a solenoid controlled air supply, 1-4 bar (15-60 psig).

4. Wire the Power, Outputs, Contact Relays and the HYDRA Sensor to the HYDRA C22 Analyzer.

Familiarize yourself with the MENU Structure of the HYDRA C22 Analyzer, Section 3 (above).

4.1 SET-UP AND CONFIGURATION

The HYDRA C22 analyzer is configured as shown below. Changes to the default configuration can be

easily made as described in Section 3 above.

4.1.1 Set Up Menus

Ch 1 Setup Menu Settings Settings

Plot 4-20 1

Sample .1 m

4mA1 0.100 ppb

20mA1 50.00 ppm

2 On > 10.00 ppm

2 Off < 9.500 ppm

Timer 1 : periodic

Per 0d00 :30 :00

Now 0 00 :00 :00

On 0 00 :00 :00

Off 0 00 :00 :15

Timer 2 : oneshot↑ Now 0 00 :00 :00

On 0 00 :00 :00

Off 0 00 :01 :15

Cl coef 0.004

Cl comp On

TC .333 %/°C

Isopot XXX.X mV

Nitrate Ion value

Noise filter 5


TC .333 %/°C

Isopot XXX.X mV

Chloride Ion value

Noise filter 5



4mA 2.00 pH (0.1 ppb)

20mA 12.00pH(50 ppm)

pH or (ppb/ppm NH4+)

Noise filter 5

4.1.2 Set Up Menu, MASTER/SLAVE

Master


Plot 4-20 1

Sample .1 m

4mA1 0.1 ppb

20mA1 50.00 ppm

1 On > 10.00 ppm

1 Off < 9.500 ppm

Timer 1 : periodic

Per 0d00 :15 :00

Now 0 00 :00 :00

On 0 00 :00 :00

Off 0 00 :00 :30

Timer 2 : periodic Per 0d00 :30 :00

Now 0 00 :00 :00

On 0 00 :00 :00

Off 0 00 :00 :30


On 0 00 :00 :00

Off 0 00 :01 :30

Cl coef 0.10

Cl- comp On

TC .333 %/°C

Isopot XXX.X mV

Equilib 9.24 pH

Dissoc 1.000 On

Noise filter 5


TC .333 %/°C

Isopot XXX.X mV

Noise filter 5


4mA 2.00 pH

20mA 12.00 pH

Noise filter 5

Slave


Plot 4-20 1

Sample .1 m

4mA1 0.1 ppb

20mA1 50.00 ppm


Ch 1 Setup Menu,

cont’d

1 On > 10.00 ppm

1 Off < 9.500 ppm


On 0 00 :00 :00

Off 0 00 :01 :30

Cl coef 0.10

Cl- comp On

TC .333 %/°C

Isopot XXX.X mV

Equilib 9.24 pH

Dissoc 1.000 On

Noise filter 5


TC .333 %/°C

Isopot XXX.X mV

Noise filter 5


4mA 2.00 pH

20mA 12.00 pH

1 On > 7.50 pH

1 Off < 7.40 pH

Noise filter 5

4.1.3 Configure and Trim Menu

The Configure and Trim is configured as shown be and does not require any adjustments.

Menu Settings

Passwords No Pass Words (not configured)

Default display 0 (not configured)

4-20 assign 4-20 1 : Ch1 PV

4-20 2 : Ch3 PV

Manual Mode Ch1 man mode on: 4-20 1

Initial ch1 manual setting: Bumpless

Ch1 auto entry: timer 2

Ch2 man mode on: nothing


Ch2 auto entry: unused

Ch3 man mode on: 4-20 2



Relay assign/test Relay 1 timer 1

Relay 2 Ch1 PV

(Relays 3-8 set to missing)

PID Assign PID A unused

PID B unused


Clock and timers Clock: Software

Hide Clock N

Hide Rate Y

Hide Flash N

Man trig OK Y

Timer 1: periodic

Timer2: oneshot↑

Retriggerable N

Resettable N

Trig 2 timer 1

(Timers 3-8 unused)

Logic gates All unused

Ion Species Ch1 ion NO3-N

Ch2 ion Cl-

General No Menu

°C/°F & temp cal 1 Trim °C .0

Unit 200.0 °C

4-20 Trim/Test (not configured)

Millivolt trim (not configured)

4.1.4 Configure and Trim Menu, MASTER/SLAVE

MASTER

Menu Settings



4-20 assign 4-20 1 : Ch1 PV

4-20 2 : Ch3 PV







Relay assign/test Relay 1 Ch1 PV

Relay 2 timer 2

Relay 3 timer 1

Relay 4 timer 2

PID Assign PID A & B unused


Hide Clock N

Hide Rate Y

Hide Flash N

Man trig OK Y

Timer 1: periodic

Timer 2: periodic


Timer3: oneshot↑

Retriggerable N

Resettable N

Trig 2 AND A

Logic gates AND Gate A

In Timer 1

In Timer/2

OR Gates A, B, C Not Used

AND Gate B, C Not Used


Ch2 ion Cl-

General No Menu


Unit 200.0 °C



SLAVE

Menu Settings



4-20 assign 4-20 1 : Ch1 PV

4-20 2 : Ch3 PV







Relay assign/test Relay 1 Ch 1 PV

Relay 2 Ch 2 PV

(Relays 3-8 set to missing)

PID Assign PID A unused

PID B unused


Hide Clock N

Hide Rate Y

Hide Flash N

Man trig OK Y

Timer 1: oneshot↑

Retriggerable N

Resettable N

Trig 2 Ext /1

(Timers 3-8 unused)

Logic gates All unused


Ch2 ion Cl-


General No Menu


Unit 200.0 °C



4.2 CALIBRATION

The HYDRA Nitrate Analyzer was calibrated at the factory using the Two Point Calibration described

below. The sensor was assembled and placed beaker of equilibration solution for 8-12 hours before

starting the calibration. The Chloride Ion and Nitrate Ion electrodes sensing membranes require several

hours to properly hydrate/ equilibrate to the measured solution. The calibration sets the zero potential

and slope for each of the sensors into the analyzers memory.

Since the factory calibration characterizes the complete measurement system the initial user calibration

should only require a standardization of the Nitrate Ion Electrode once the HYDRA has equilibrated to

the process solution.

The Factory Calibration and all subsequent calibrations should be performed in the following sequence:

1. Temperature Calibration

2. Chloride Electrode calibration in 1 ppm (or 10 ppm) and 100 ppm solutions (2 point)

3. Nitrate Electrode calibration in 1 ppm (or 10 ppm) and 100 ppm solutions (2 point)

Calibration checks should be performed weekly by comparison to a grab sample or immersing the

HYDRA sensor into a standard solution with known pH, Cl- and NO3

--N values. Performing a Single Point

Calibration will eliminate any offset found in the calibration check. Continuous drifting of the Chloride or

Nitrate ion reading may indicate the electrode needs to be replaced. (See Section 6 Trouble Shooting

below)

Two Point Calibration is required whenever an electrode is replaced, pH, Chloride or Nitrate. Two Point

Calibrations are also recommended every two months to verify the response of the electrodes is greater

than 50 mV/decade.

4.2.1 Recommended Materials

pIon Calibration Solutions

1. 1 ppm Cl-, 500 ml (Part# 2010453)

2. 100 ppm Cl-, 500 ml (part# 2010454)

3. 1 ppm NO3--N, 500 ml (Part# 2010451)

4. 100 ppm NO3--N, 500 ml (part# 2010452)

pH Calibration Solutions (optional)

1. pH 4.01, 500 ml (Part # 2010100) or 1.00 ppm NH4-N (Part # 2010445)

2. pH 7.00, 500 ml (Part # 2010101) or 100 ppm NH4-N (Part # 2010446)

Accessories


1. 1 liter plastic beakers

2. Distilled Water for rinsing

3. Calibrated thermometer with 0.1 °C graduations

4. Stir plate with magnetic stir bars.

4.2.2 Temperature Calibration

Place the HYDRA sensor in a beaker of water so that the bottom 3 inches (7.6 cm) of the body is

immersed. Allow the sensor to equilibrate for 10 minutes. Verify the displayed temperature agrees with

the thermometer. If not, then adjust the temperature in the Configure/Trim > °C/°F & temp cal > 1 Trim

°C menu to agree with the thermometer. This calibration was performed in the factory calibration but it

is advisable to perform a temperature check every 2-3 months.

4.2.3 Single point Calibration

Single Point Calibrations are used to standardize the sensor’s reading to a known value typically to

eliminate errors caused by drift or large changes in the makeup of the measured solution. A Single Point

Calibration adjusts the base potential of the sensor by shifting the response curve to a higher or lower

level but it does not affect the slope (mV/ppm) of the curve.

Single point calibration is available for each of the measured parameters in the appropriate Buffer

Menu, Channel 1 Buffer for the NO3--N, Channel 2 Buffer for the Cl

- and Channel 3 Buffer for pH or NH4

+.

(See the Single Point Calibration Screen table below)

Immerse the front end of the sensor into a container of the calibration solution, enter the value of the

calibration solution or the value derived from a grab sample into the “1 (ion) xxx ppm” line of the

Buffer menu as described in Section 3.2.5 above. Accept the reading when stable by pressing either of

the MENU SELECT keys. The lower line in the menu, the Cal line will show the new mV value associated

with the entry.

***Important Note for Nitrate Calibrations*** When using the 1 ppm and 100 ppm NO3--N calibration

solutions to calibrate the HYDRA C22 analyzer the chloride ion compensation, the “Cl comp” line in the

Channel 1 Setup menu should be turned on, it is on by default.

If the Single Point Calibration is the first point in a Two Point Calibration it is customary to use the

solution with the lowest value for the single point calibration. There are no restrictions on the value

entered in the “1 (ion) xxx ppm” line of the Buffer menu; it can be higher or lower than the value in line

2 of the menu. For the pH calibration the zero point is set with pH 7.0 calibration buffer and the slope is

set with the pH 4.01 calibration buffer.

Single Point Calibration Screens

Channel Screen Recommended Solution

Ch1 Buffer (NO3-N) 1NO3-N 1.000 ppm

Cal 460.0 mV

1.0 ppm NO3-N (Part# 2010451)

or Grab Sample value

Ch2 Buffer (Cl-) 1Cl- 1.000 ppm

Cal 165 mV

1.0 ppm Cl (Part# 2010453)



Ch3 Buffer (pH) 1 pH 7.00 pH

Cal 3.1 mV

pH 7.0 Buffer (part# 2010101)


Ch3 Buffer (NH4-N) 1NH4-N 1.000 ppm

Cal 320.0 mV

1.0 ppm NH4-N (Part# 2010445)


4.2.4 Two point Calibration

The second point of a Two Point Calibration sets the slope of the sensor, the mV per decade. The slope is

calculated by comparing the millivolt values and ppm values in the “1NO3-N 1.00 ppm” line to the

values in the “2NO3-N 100 ppm” line of the Buffer Menu. The concentration of the solution used for

the second point should be at least 10 times higher than the value used in the first point of the

calibration. The recommended calibration standards for both the nitrate ion and chloride ion

calibrations are 1 ppm and 100 ppm. Perform a two point calibration whenever an electrode is replaced.

After completing the single point calibration, see section 4.2.3 above, rinse the sensor with distilled

water and gently dab it dry with a paper towel or soft tissue. Carefully rinsing the sensor prevents errors

in the calibration due to carryover from the first solution. Place the sensor in the second solution, either

the pH 4.01 buffer or one of the 100 ppm solutions and wait for the reading to stabilize before accepting

the value. See section 3.2.5 above for further instruction.

4.2.5 Chloride Ion Compensation

Chloride ions have a positive interference on the Nitrate Ion Electrode, the nitrate reading is higher than

the actual value. The Chloride Ion Compensation, Cl comp, adjusts the measured nitrate ion

concentration using the measured chloride concentration and the interference/selectivity value, the Cl

coef, and subtracts the resulting amount from the Nitrate Ion Signal. The Cl coef value in the NO3-N Set

Up screen allows the interference ratio to be adjusted as needed. The default setting is Cl coef = .004

which is 250 chloride ions produce the same signal as 1 nitrate ion, Ks = 0.04 would change the

correction to 25:1. The 0.004 correction factor is good for most solutions with levels of chloride greater

than 50 ppm.

Each Chloride Ion Electrode should have similar characteristics but adjustments are necessary when the

chloride electrode is replaced or when low levels of chloride are present in the solution. If the nitrate ion

concentration is less than expected when compared to a grab sample measurement then adjust the Cl

coef value to a smaller value. Adjusting from 0.004 > 0.002 for example would increase the chloride to

nitrate ion ratio from 250:1 to 500:1 thereby slightly increasing the displayed nitrate ion concentration

by subtracting less in the compensation. See section 3.2.6 above.


5.0 MAINTENANCE

5.1 MAINTENANCE SCHEDULE

The HYDRA sensor requires little maintenance since most of the required cleaning is accomplished by

the Air Blast Spray Cleaner. Determining the proper cleaning cycle and duration for the application will

keep the front end of the sensor clean for extended periods but weekly inspection of the sensing end is

recommended.

Weekly calibration checks versus a grab sample are recommended to minimize any drift in the sensor.

Once the stability of the sensor has been established in the process, the time between calibration

checks can be adjusted. A calibration check must occur at least once per month.

The HYDRA should be checked monthly in calibration solutions for proper span of both the Nitrate and

Chloride electrodes. The electrodes start life with a span in the 55 mV/decade range and drop off into

the 40 mV/decade range as they age. Readings below 40 mV/decade indicate the electrode should be

replaced. Depending on the characteristics of the water being measured the Ion Selective electrodes

should last 3-6 months.

5.2 CLEANING THE SENSOR

The HYDRA sensor can be rinsed with water and wiped with a soft brush or cloth to remove most

coatings. DO NOT clean the Chloride or Nitrate ion electrodes with a stiff brush or vigorous wiping as the

sensing membrane is easily scratched or torn. DO NOT use alcohols or organic solvents to clean the

sensor, the Nitrate electrode will be irreparably harmed. The sensor can be soaked in a weak detergent

solution to remove oily coatings or dilute HCl, 2-3%, for 15 minutes to help remove stubborn coatings.

The pH, Chloride ISE and HYDRA housing can be cleaned in a more rigorous manner since the plastic

body, Chloride ISE and glass membrane are more durable than the Nitrate Ion Selective Electrode.

5.3 REPLACING THE ELECTRODES

The three electrodes, Nitrate, Chloride and pH are easily replaceable by simply removing the electrode

guard, screwing out the old sensor and screwing in the new one using the supplied installation tool.

Make sure no water gets inside the sensor when removing the electrodes. Water will cause the internal

electronics to fail. If the electronics are compromised the complete HYDRA sensor must be replaced.

The nitrate electrode, the chloride electrode and pH electrodes are combination electrodes. The

reference electrodes are combined to a single signal which is used for all the measurements.

Apply a thin film of o-ring lubricant to the o-rings on the electrode before installing it into the sensor

housing. Use the supplied electrode installation tool to remove or install electrodes into the sensor. The

use of pliers or other tools is not recommended as they may crack the electrode housing.


6.0 TROUBLESHOOTING

Problem Possible Cause Remedy

NO3--N Reading Low Dirty Coated electrode Clean sensor:

Soak in 2% HCl for 5 minutes to

remove algae or

Rinse with weak detergent 10-15

seconds solution to remove oils

Soak in tap water for 30 minutes

after either cleaning method.

Increase frequency of the air

blast cleaner, See Section 4.1.1

Old Expired NO3 ISE Perform two point calibration,

the slope > 40 mV/decade if not

replace NO3 Sensor

Inaccurate Chloride

compensation

Verify Chloride ISE reading with

single point calibration

Adjust Cl coef (see section 4.2.5)

NO3--N Reading High Nitrate Sensor has drifted Perform a single point

calibration.

Low or No Chloride ion

Compensation

Verify Cl comp is ON

Verify Chloride ISE reading with

single point calibration

Adjust Cl coef (see section 4.2.5)

Interfering Ions Present in

Sample

Influx of interfering ions causing

error, wait for ions to clear the

process, Iodide, Bromide, HS-,

Chlorate, Chlorite, Carbonate,

Bicarbonate, Nitrite

No Response to Changing Nitrate Bad Electrode Visually inspect membrane for

cuts, if torn replace electrode

Remove the electrode examine

for breakage, torn o-rings,

corrosion or moisture, if any of

these issues are present then,

Switch out old electrode with a

new electrode, check response,

if good recalibrate the HYDRA

Bad Sensor Switch out old electrode with a

new electrode, check response,

if still bad examine electrode

tube for signs of moisture.

If present remove sensor from

installation and allow the sensor

to dry out. Retest with a new

electrode, if it still fails return it

to the factory for refurbishment.


7.0 ENGINEERING DOCUMENTATION

7.1 SPECIFICATIONS

Sensor

A Three Electrode system with spray cleaner, Nitrate ISE (NO3-- N) is the primary measurement. The

Chloride ISE is used to compensate the NO3- signal. An optional pH electrode is available for pH

measurement. The Sensor is waterproof with an ingress rating of IP 68.

Measurement Range

NO3-- N: 0.1 to 1000 ppm

Operating Temperature

0° C to 40° C (32° F to 104° F)

Min/Max Flow Rate

Minimum 0.1 m/s

Maximum 3.0 m/s

Wetted Materials

PVC, PES, PVDF, PTFE, Viton, Glass, 316 SS

Accuracy

± 3% of reading, dependent on Calibration

Response Time

T90 1 minute

Electrode Life

ISEs: 4- 6 months, typical

pH electrode: 6-12 months, typical

C22 Analyzer

Measurements

Nitrate: 0.01 to 1000 ppm as NO3-- N

Chloride: 0.01 to 1000 ppm

pH: 0 to 14 pH or NH4+: 0.1 to 1000 ppm

Temperature: 0° C to 100° C (32° F to 212° F)

Compensation

Chloride: 0.1 to 1000 ppm

Display

2.5” X 1.75” backlit LCD, 4 lines of Text & Graphical

Enclosure

NEMA 4X, LxWxD: 5.7” x 5.7” x 7

Outputs

(2) 4-20 mA maximum load 800 ohms @ 24 VDC

Configured: 0.1 to 20 mg/l NO3-- N; and 0 – 14 pH or 0.1 to 20 mg/l NH4

+

Optionally up to (4) 4-20 mA outputs


Input Power

110/220 VAC @ 50/60 Hz

Alarm Relay Ratings

(2) SPDT 230 VAC/5A or 30 VDC/5A resis0ve max.

Relay (1) Spray Cleaner, Relay (2) Alarm

Optionally up to (8) Relays

7.2 OUTLINE & DIMENSIONAL DRAWING

7.2.1 Hydra Sensor Dimensions

7.2.2 C-22 Dimensions

Panel Mount Dimensions and Cut-out Pattern


Wall Mounting Dimensions, Screw Hole Pattern

7.2.3 Sun Shield


7.3 WIRING DIAGRAM

7.3.1 Sensor Color Coded Diagram

The White wire is either the pH signal or Ammonium signal on the option 3 electrode designs.

7.3.2 Instrument – Terminal Layout/Connections


8.0 ORDERING INFORMATION

The HYDRA Nitrate Analyzer is a complete measurement system including the C22 analyzer/controller

(p/n 16LA2221.LA00) and the multiple parameters HYDRA Sensor (p/n 1290030-3). The Nitrate Ion

measurement is fully compensated for the effects of changes in the Chloride ion concentration in the

measured solution. The sensor features an Air Blast Cleaner that minimizes maintenance in the dirtiest

applications.

8.1 PART NUMBERS/MODEL NUMBERS

Part No. Model and Product Description

1290030-3 HYDRA NO3-N Sensor,

Complete, NO3, Cl-, pH, Temp, Spray Cleaner head and 30 ft. cable

1290030-4 HYDRA NO3-N Sensor, (No pH Sensor)

Complete, NO3, Cl-, Temp, Spray Cleaner head and 30 ft. cable

1290030-5 HYDRA NO3-N Sensor,

Complete, NO3-, Cl

-, NH4

+, Temp, Spray Cleaner head and 30 ft. cable

16LA2221.L100 HYDRA C22 NO3-N Analyzer, Standard

Cl- compensated & pH, (2) 4-20 mA output, 0.1 – 50 ppm NO3-N and (2) relays

16LA2221.L1L0 HYDRA C22 NO3-N Analyzer, SLAVE


16LA2421.L1K0 HYDRA C22 NO3-N Analyzer, MASTER


16L02221.L000 HYDRA C22 NO3-N Analyzer, Standard

Cl- compensated, no pH, (2) 4-20 mA output, 0.1 – 50 ppm NO3-N and (2) relays

16L02221.L0L0 HYDRA C22 NO3-N Analyzer, SLAVE


16L02421.L0K0 HYDRA C22 NO3-N Analyzer, MASTER


16LB2221.LT00 HYDRA C22 NO3-N Analyzer, Standard, Cl- compensated, NH4+, (2) 4-20 mA

outputs, 0.1 - 20 ppm NO3--N, 0.1 - 20 ppm NH4+ and (2) relays

16LB2221.LTL0 HYDRA C22 NO3-N Analyzer, SLAVE, Cl- compensated, NH4+, (2) 4-20 mA outputs,

0.1 - 20 ppm NO3--N, 0.1 - 20 ppm NH4+ and (2) relays

16LB2421.LTK0 HYDRA C22 NO3-N Analyzer, MASTER, Cl- compensated, NH4+, (2) 4-20 mA

outputs, 0.1 - 20 ppm NO3--N, 0.1 - 20 ppm NH4+ and (4) relays

8.2 ACCESSORIES

Part No. Accessories Description

1000254-XX Immersion Assembly, 1 ½” Slip x 45°, 1 ¼” NPT sensor connection and 1 ½” Slip x Cable feed through Elbow End Cap, XX= Length in ft.

1000254-99 Immersion Assembly, 1 ½” Slip by 45° 1 ¼” NPT sensor connection and 1 ½” Slip x Cable feed through Elbow End Cap, Fittings Only , User supplied Pipe (1 ½” Pipe)

2000255-1 2” Handrail Swivel Mounting Bracket

2010451 Nitrate Calibration solution, NO3-N, 1 ppm (500 ml)

2010452 Nitrate Calibration solution, NO3-N, 100 ppm (500 ml)

2010453 Chloride Calibration solution, 1 ppm (500 ml)

2010454 Chloride Calibration solution, 100 ppm (500 ml)


2010100 pH 4 Buffer Calibration solution (500 ml)

2010101 pH 7 Buffer Calibration solution (500 ml)

2010445 Ammonium Calibration solution, NH4-N 1 ppm

2010446 Ammonium Calibration solution, NH4-N 100 ppm

1000260-1 Sun Shield with Pole Mounting Hardware (Vertical Pole)

1000260-2 Sun Shield with Rail Mounting Hardware (Horizontal Rail)

1000300-1 4-20 mA USB Data Logger

8.3 SPARE PARTS

Part No. Spare Parts Description

2005086.VIT Nitrate Electrode Cartridge (recommended spare)

2005008.VIT Chloride Electrode Cartridge (recommended spare)

2005145.VIT pH Electrode Cartridge (recommended spare)

2005084.VIT Ammonium Electrode Cartridge (recommended spare)

3300854-1 Replacement Spray Nozzle

3501078-1 PVC Front Sensor Guard

3500007 Electrode Replacement Tool

Documents

Hydra Nitrate Manual B1814 - Electro-Chemical Devices Nitrate Manual F14.pdf · 2. Check the contents of the shipping container with the items and quantities shown on the packing