Fluke Biomedical 875 Victoreen - Manual (Page 34)

Maintenance, Calibration, and Troubleshooting
Troubleshooting
5
5-3
Test Procedure TP876A-1-108
Factory test procedure, rm electronic
alignment of the 876A-1 dix A.
5.3 Troubleshoo
The 875 High-Range Co r has been assembled
y techniques and with parts selected for the reliability required in a nuclear application. Any repairs
safety-
m.
ircuit boards must be returned to
There are two self-contained system tests avai inment Monitor 875, the Channel Test and
the ECS Test. In both ca
desired output.
mportant di Test and the ECS Test: the former applies an input
the readout module (that is, to the first electronic circuit in the Containment Monitor); however, it does
plates,
libration section is also recommended for
If
4. lfunction exists in the fail/safe circuitry.
Essentially, the Ch ntally verifies all
o
1.
ircuit
4. Alarm circuits
6.
TP876A-1-108, contains this information necessary to perfo
-108 Readout Module. This procedure is included in Appen
ting
ntainment Monitor is safety-related equipment. The monito
b
made to the detector or readout (other than replacement of parts listed in Section 5) may void the
related rating. The troubleshooting procedure that follows is a guide to isolating a fault in the syste
Replacement of parts is at the printed circuit board level only. Printed c
Fluke Biomedical for service.
lable in Conta
ses, the procedure is to put a known input into the system, and to look for the
fference between the Channel There is an i
to
not test the detector or the cables connecting the detector to the readout module. In addition, the Channel
Test applies a DC voltage, whereas the ECS Test applies a ramp voltage to the detector
monitoring the resultant current into the readout module.
The digital multimeter mentioned in Table 5-1 of the ca
troubleshooting.
the ECS Test gives a favorable result, the following conditions exist:
1. The detector cannot have any appreciable malfunction.
2. The cables must have continuity.
3. The ECS board and power supply board must be operative.
It is highly improbable that any ma
5. The amplifier, meter and alarm circuitry must be operative.
annel Test verifies only #5 of the above. However, in doing so, it incide
f the power supplies except the high voltage power supply.
For clarity, troubleshooting is divided into six divisions:
Power supplies
2. Input c
3. Meter circuit
5. ECS board
Overall fail circuitry