Yokogawa EXA DC402 Dual-Channel Conductivity Analyzer - Manual (Page 74)

IM 12D08E02-01E
Appendix 2 11-1
11. APPENDIX 2 QUALITY INSPECTION
Quality
Inspection
Standards
DC402G
Converter for Conductivity or Resistivity
QIS 12D08E02-01E
1st Edition: Feb. 2007
2nd Edition: Sep. 2013
1. Scope
This inspection standard applies to the DC402G Converter for Conductivity or Resistivity.
2. Inspection Items
2.1 Insulation resistance test
* 2.2 Dielectric strength test
2.3 Current output test
2.4 Contact operation test
2.5 Temperature indication check
2.6 Resistance indication check
Note: Items marked with an asterisk (*) may only be confirmed by a test certificate.
3. Inspection Methods, Standards and Conditions

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 Sections 3.1.

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 converter, turn on the
power again, and enter the inspection mode to restart the tests.
3.1 Insulation Resistance Test
Apply 500 V DC between the power supply terminals shorted together (1 and 2) and the
protective earth terminal outside the case. The insulation resistance must be 100 MΩ or
greater.
3.2 Dielectric Strength Test
Apply 1400 V AC, an AC voltage of substantially sinusoidal waveform with a frequency of
50 Hz or 60 Hz, between the power supply terminals shorted together (1 and 2) and the
protective earth terminal outside the case, for at least 2 seconds. The insulation must
withstand this voltage. (The sensed current should be 15 mA.)
3.3 Current Output Test
Connect the testing circuit as shown Figure 1 and set the equipment as follows:
Decade resistance box 1 (temperature simulation input): 960.9 [Ω]
Decade resistance box 2 (conductivity simulation input): 160 [Ω]
The power supply voltage should be set in accordance with the specifications of the
converter.
User the following procedure to enter the inspection mode.
(1) Entering Service Code 87.
a. Press the [] key. The message display will show “SETP.”
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 [] key eight times. The data display will show “80” with the first digit of
8 flashing.