EUTECH INSTRUMENTS 2-WIRE PHORP TRANSMITTER User manual

68X256901 Rev 1 10/99
EUTECH INSTRUMENTS
2-Wire pH or ORP Transmitter
Operating Instructions
1Preface
Thank you for purchasing the Eutech pH or ORP Transmitter.
This manual serves to explain the correct installation and operations of
the XTR Transmitters. Other Transmitters available individually are: pH,
ORP (REDOX), Conductivity, Dissolved Oxygen and Temperature.
•EC-PH-XTR;
•EC-ORP-XTR;
•EC-CON-XTR;
•EC-DO-XTR; and
•EC-TEMP-XTR.
The information presented in this manual is subject to change without
prior notice, as improvements are made to the product. While Eutech will
endeavor to try its best to inform the market, this does not represent a
commitment on the part of Eutech Instruments Pte Ltd.
Eutech Instruments does not accept any responsibility for damage or
malfunction of the unit due to improper installation or operation of the
Transmitter.
Copyright 1999 Eutech Instruments Pte Ltd. Version 1.0. All rights
reserved.
Eutech Instruments Pte Ltd. Blk 55 Ayer Rajah Crescent #04-14/24,
Singapore 139 949. Tel: [phone]; Fax: [phone]; e-mail:
[email protected]; Home page: http://www.eutechinst.com
2Introduction
The Transmitter is used for the continuous measurement of pH, ORP
(REDOX), Conductivity, Dissolved Oxygen or Temperature, in conjunction
with an appropriate sensor. Data output is via 4-20 mA current output.
The Transmitter is housed in a IP65 enclosure, with openings for input
and 4-20mA output.
3Diagram and Dimensions (in mm)
4Installation
Operating with one or several Transmitters:
Figure 1- Operating with 1 Transmitter
Figure 2- Operating with several transmitters
5Electrical Connections
NOTE: In electrically “noisy” environments, select ‘Symmetrical’ mode of
operation and connect a stainless steel rod (Potential Matching
Pin - PMP) as shown above. Ensure both the PMP and pH or
ORP electrodes are immersed into the solution, even when
performing calibration.
6Before Calibration
Remove cover of Transmitter and ensure that electrode is correctly
connected as above. Connect Amp meter to the 4/20mA output of
Transmitter (Appendix 1).
7pH Transmitter Calibration
1) Calibrate in pH 7.00 buffer first, and then in either pH 4 or pH 10.
2) First, immerse clean pH electrode into a container with fresh pH 7.0
buffer solution;

68X256901 Rev 1 10/99
3) Amp meter should read 12mA; if not, calibration is necessary;
4) Locate “Offset adjustment” trimmer; Using a fine screwdriver,
slowly turn trimmer till Amp meter reads 12mA;
5) For greater accuracy, adjust slope with pH 4 or 10;
6) Rinse probe in de-ionised water and immerse in either pH 4.01 or pH
10.01 buffer solution;
7) In pH 4.01, the output is 8.54mA;
8) In pH 10.01, the output is 15.44mA;
9) Using a fine screwdriver, slowly turn trimmer, marked ‘slope’, till Amp
meter reads correct mA value with respective buffer solutions.
10) Remember to disconnect Amp meter and close cover.
NOTE: For other buffer values, expected current output is based on:
mA = {(16/14) x buffer pH value} + 4mA
8ORP Transmitter Calibration
1) Prepare fresh Standard solutions, such as 255mV, 470mV.
2) Short ORP inputs and observe Amp meter display;
3) Amp meter should read 4mA; if not, calibration is necessary;
4) Locate “Offset adjustment” trimmer; Using a fine screwdriver,
slowly turn trimmer till Amp meter reads 4mA;
5) For greater accuracy, adjust the slope with Standard calibrating
solutions;
6) Rinse probe in de-ionised water and immerse in standard solution;
7) In 255mV solution, the output is 8.08mA;
8) In 470mV solution, the output is 11.52mA;
9) Using a fine screwdriver, slowly turn trimmer, marked ‘slope’, till Amp
meter reads correct mA value with respective Standard solutions.
10) Remember to disconnect Amp meter and close cover.
NOTE: For other Standard values, expected current output is based on:
mA = {(16/1000) x ORP value of Standard solution} + 4mA
9Specifications
Model ECPHXTR ECORPXTR
Range 0.00 – 14.00 pH 0 to +1000mV
Accuracy ±0.05 pH ±3 mV
Calibration Offset ±1pH
Slope 80 – 120%
Offset ±50mV
Slope 80 – 120%
Input Asymmetrical or Symmetrical (with Potential Matching
Pin)
Output 4-20 mA
Operating
Voltage DC 12 V to 24 V
Load 100 Ohms max. for 12 V;
600 Ohms max. for 24V
Housing 77 x 77 x 28 mm, field mountable
10 Appendix 1
Connecting Amp Meter for Calibration
Figure 3- Method One
Figure 4- Method Two
11 Ordering Information
pH
Item Cat Code
pH Transmitter ECPHXTR
Combination pH Electrode, General, integral 5m cable ECARTSO05B
Combination pH Electrode, w/PMP, integral 5m cable ECARGTSO05B
Dissolved Oxygen
Item Cat Code
Dissolved Oxygen Transmitter ECDOXTR
General Purpose D.O. probe, 0.5 – 40 ppm, Industrial,
integral 5m cable ECDOGEN
General Purpose D.O. probe, 0 – 10 ppm, Industrial,
integral 5m cable ECDOTPll
ORP
Item Cat Code
ORP Transmitter ECORPXTR
Combination Platinum ORP Electrode, w/PMP,
integral 5m cable ECHTPTTSO05B
Combination Gold ORP Electrode, w/PMP, integral
5m cable ECHTAUTTSO05B
Conductivity
Item Cat Code
Conductivity Transmitter ECCONXTR
2-Pin SS,k=1.0, integral 3m cable ECCONSEN46
Temperature
Item Cat Code
Temperature Transmitter ECTEMPXTR
Pt 100 probe, SS316 ECPT10001M or
ECPT10005M
Power Supply
Item Cat Code
120V Power Supply EC-120-XTR
220V Power Supply EC-220-XTR