Yokogawa DO202 2-Wire Dissolved Oxygen Analyzer - Manual (Page 70)

IM 12J05C01-01E
Appendix 2-5
A-2-2. DO202S 2-Wire Dissolved Oxygen Transmitter
Quality
Inspection
Standards DO202S
Dissolved Oxygen Transmitter
QIS 12J05C01-21E
1st Edition: Feb. 2007
1. Scope
This inspection standard applies to the DO202S Dissolved Oxygen Transmitter.
2. Inspection Items
2.1 Insulation resistance test
* 2.2 Dielectric strength test
2.3 Current output test
2.4 Temperature indication check
* 2.5 Galvanic indication check
* 2.6 Polarograph indication check
Note: Items marked with an asterisk (*) may only be confirmed by a test certificate.
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, and for the connections for the dielectric strength test,
follow the instructions in Section 3.2.
z
Performance tests should be done in the inspection mode where the tests from Section 3.3
through Section 3.6 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
(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 18) and the earth
terminal (G). The insulation resistance must be 100 MΩ or greater.
3.2 Dielectric Strength Test
Apply 600 V AC, an AC voltage of substantially sinusoidal waveform with a frequency of 50 Hz
or 60 Hz, between the terminals shown below, for at least 2 seconds. The insulation must
withstand this voltage. (The sensed current should be 10 mA.)
(1) Between the power supply terminals shorted together (+ and –) and the earth terminal (G)
(2) Between the input terminals shorted together (11 to 18) and the earth terminal (G)
(3) Between the input terminals shorted together (11 to 18) and the power supply terminals
shorted together (+ and –)
3.3 Current Output Test
Connect the testing circuit as shown Figure 1 and set the equipment as follows:
Decade resistance box: 1019.5 Ω
DC generator 1: 0 μA
DC generator 2: 0 μA
DC source: 24 V DC
User the following procedure to enter the inspection mode.