Yokogawa EXA PH202 2-Wire pH/ORP Analyzer - Manual (Page 113)

IM 12B07D02-01E
Appendix 12-1
12. APPENDIX 3 QUALITY INSPECTION
12-1. PH202G, PH202SJ 2-Wire pH/ORP Transmitter
Quality
Inspection
Standards
PH202G, PH202SJ
2-Wire pH/ORP Transmitter
QIS 12B07D02-01E
1st Edition: Feb. 2001（YK）
6th Edition: Mar. 2007（YK）
1. Scope
This inspection standard applies to the PH202G, PH202SJ 2-Wire pH/ORP Transmitter.
2. Inspection Items
2.1 Insulation resistance test
2.2 Current output test
2.3 Temperature indication check
2.4 pH indication check
2.5 ORP indication check
3. Inspection Methods, Standards and Conditions
z
Connect the testing circuit as shown in Figure 1. Allow the instrument to warm up for at least
5 minutes before conducting the tests. For the connections for the insulation resistance test,
follow the instructions in Section 3.1.
z
Performance tests should be done in the inspection mode where the tests from Section 3.3
through Section 3.5 take place in sequence and cannot be retraced. If the reconfirmation of
a test is needed, turn off the power to the transmitter, turn on the power again, and enter the
inspection mode to restart the tests.
3.1 Insulation Resistance Test
As for the PH202G, follow the instructions below.
(1) Apply 500 V DC between the power supply terminals shorted together (+ and –) and the
earth terminal (G). The insulation resistance must be 100 MΩ or greater.
(2) Apply 500 V DC between the input terminals shorted together (11 to 17) and the earth
terminal (G). The insulation resistance must be 100 MΩ or greater.
As for the PH202SJ, follow the instructions below.
(1) Apply 125 V DC between the power supply terminals shorted together (+ and –) and the
earth terminal (G). The insulation resistance must be 9.5 MΩ or greater.
(2) Apply 125 V DC between the input terminals shorted together (11 to 17) and the earth
terminal (G). The insulation resistance must be 100 MΩ or greater.
3.2 Current Output Test
Connect the instruments as shown in Figure 1, and set them as follows.
Connect a shorting bar between terminals LOW and IMP.
Decade resistance box: 921.6 :
Standard voltage/current source: 0 mV
DC source: 24 V DC
Use the following procedure to enter the inspection mode.
(1) Entering Service Code 87
a. Press the [
] key. The message display will show “
OUTP.”
b. Press the [NO] key until the message display shows “
SERV.”
c. Press the [YES] key. The data display will show “00” with the first digit of 0 flashing.
d. Press the [š] key eight times. The data display will show “80” with the first digit of 8 flashing.
e. Press the [>] key once. The data display will show “80” with the second digit of 0 flashing.