Eutech Instruments 2-WIRE PHORP TRANSMITTER User Manual

EUTECH INSTRUMENTS

2-Wire pH or ORP Transmitter

Operating Instructions

4 Installation

Operating with one or several Transmitters:

Figure 1 - Operating with 1 Transmitter

1 Preface

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:

[e-mail]; Home page: http://www.eutechinst.com

2 Introduction

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.

3 Diagram and Dimensions (in mm)

Figure 2 - Operating with several transmitters

5 Electrical 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.

6 Before 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).

7 pH 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;

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

8 ORP 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

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
General Purpose D.O. probe, 0 – 10 ppm, Industrial,

integral 5m cable

ORP

Item Cat Code

ORP Transmitter ECORPXTR
Combination Platinum ORP Electrode, w/PMP,

integral 5m cable
Combination Gold ORP Electrode, w/PMP, integral

5m cable

ECDOGEN

ECDOTPll

ECHTPTTSO05B

ECHTAUTTSO05B

9 Specifications

Model ECPHXTR ECORPXTR

Range 0.00 – 14.00 pH 0 to +1000mV
Accuracy
Calibration

± 0.05 pH ± 3 mV

Offset ±1pH

Slope 80 – 120%

Offset ±50mV

Slope 80 – 120%

Input Asymmetrical or Symmetrical (with Potential Matching

Pin)
Output 4-20 mA
Operating

DC 12 V to 24 V

Voltage
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

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

Figure 3 - Method One