Single Gas Instrument Service Manual
Page 10
Bacharach, Inc.
Instruction
0019-9166
2.5 Printed Circuit Board (P.C.B.) Replacement
Figure 2-4.
Sensor & Motor
Wiring Diagram
Equipment Needed (Refer to Section “5.0 Replacement Parts” for Part
Nos.):
•
Phillips-head screwdriver, No. 1
•
Printed Circuit Board (P.C.B.)
Procedure:
1. Open the case as described in Section “2.1 Opening the Case.”
2. Unplug the motor connector from the P.C.B.
3. Unplug the sensor connector from the P.C.B.
NOTE:
(For SO
2
& CO Sensors only) If the Sensor is not going to
be immediately plugged into the new P.C.B., place a shorting wire
between sensor terminals R and S.
4. Remove the Switch Covers from the old P.C.B. and place them on the new
P.C.B., then replace the old P.C.B. with the new one.
5. Plug the motor connector into the P.C.B.
6. Remove the shorting wire from sensor terminals R & S (if installed); then
plug the sensor connector into the P.C.B.
7. Close the case as per Section 2.2 Closing the Case.”
8. Calibrate the Sensor with the new P.C.B. as per Section “3.0 Sensor Calibra-
tion.”
9. Discard the old P.C.B.
