2 orp measurement, Orp measurement – Yokogawa 2-Wire Dual Channel Transmitter/Analyzer FLXA21 User Manual
Page 6

<1. Wiring and Installation>
4
IM 12A01A02-12E
4th Edition : Sep. 3, 2013-00
1.3.2
ORP Measurement
The ORP measurement uses the same sensor input module as the pH measurement. It is not
uncommon to measure ORP as process variable and a pH Glass electrode as reference. This is
the case with rH measurement and with pH compensated ORP measurement.
Standard reference electrodes and an ORP/REDOX electrode are low impedance sensor inputs
Conventional ORP sensors are connected to the module as follows:
11 Temperature
12 Temperature
13 Reference
14 Solution ground
15 Metal (measure)
16 Shield
17 Shield
FLXA21
REF
TC
Liquid
Earth
ORP
For conventional ORP sensors, the jumpers are placed as illustrated:
16
15
19
17
13
18
14
12
11
PH
Input 1
Input 2
Metal sensor on Input 1.
Normal reference on Input 2.
pH Compensated ORP sensors are connected to the module as follows:
11 Temperature
12 Temperature
13 Glass
14 Solution ground
15 Metal
16 Shield
17 Shield
FLXA21
PH
TC
ORP
Liquid
Earth
For pH Compensated ORP sensors, the jumper is placed as illustrated:
16
15
19
17
13
18
14
12
11
PH
Input 1
Input 2
Metal sensor on Input 1.
pH glass (as reference) on Input 2.