TM 10-4610-232-34
Table 2-1. Direct Support Troubleshooting Guide (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
9.
Raw water pump runs but Iight does not come on. Light test okay. (Ref. Schematic diagram FO-1, sheet 1, schematic
line 163).
Shut down ROWPU and generator. Refer to electrical drawings in Appendix D. Remove the #2B wire from PL8 (REF:
Interconnection diagram FO-2, Sheet 11). Remove the #231 wire from MS3 (REF: Interconnection diagram FO-2,
Sheet 10). Check continuity, point-to-point, from K12(A1X) (REF: Interconnection diagram FO-2, Sheet 6) to PL8
(wire #269). Check continuity from T1(X2) (REF: Interconnection diagram FO-2, Sheet 10) to PL8 (wire #2 B).
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace LTK1 (REF: Interconnection diagram FO-2, Sheet 7) if its contact is open (para. 2-23).
(c) Replace PL8 if all the continuity checks are okay (para. 2-22).
10. Raw water pump motor starter (MS3) does not pull In (Ref. Schematic diagram FO-1, sheet 6, schematic lines 619-621,
control circuits; schematic diagram FO-1, sheet 5, schematic 532-534, power circuits).
Shut down ROWPU and generator. Remove the motor starter coil wires. Use a multimeter and check resistance across
the coil connections. It should be near zero.
Replace the coil if resistance is infinity (open) or shorted (para. 2-25).
11. Raw water pump motor starter (MS3) pulls in but does not run. (Ref. Schematic diagram FO-1, sheet 6, schematic lines
619-621, control circuits; sheet 5, schematic lines 532-534, power circuits).
Step 1. Shutdown ROWPU and generator. Turn circuit breaker CB4 (REF: Interconnection diagram FO-2, Sheet 10)
off and disconnect connector P21 (REF: Interconnection diagram FO-2, Sheet 16) from the control panel.
Use a multimeter and check continuity across each pair of motor control contractors. Manually engage the
starter contacts during testing. The reading should be zero.
Replace the motor starter contactor if any pair is open (para. 2-25).
Step 2. Remove the contactor block from the starter and check for burned, arced over contacts.
Replace the motor starter contactor if they are damaged (para. 2-25).
12. Raw water pump motor starter auxiliary contact does not operate correctly. (Ref. Schematic diagram FO-1, sheet 6,
schematic line 620 and sheet 11, schematic line 1107).
Shut down ROWPU and generator. Refer to the electrical drawings in Appendix D. Remove the wires from the
auxiliary contact. Use a multimeter and check for correct operation when the starter contacts are manually engaged
and when they are open,
(a) If the hold-in contact (line 620) does not operate correctly, replace the starter (para. 2-25).
(b) If the control contact (line 11 07) does not operate correctly, replace the auxiliary contact block (para.
2-25).
CIRCUIT BREAKERS 440 VAC.
A circuit breaker will not reset.
NOTE
This procedure does not apply to the distribution or raw water pump circuit breakers.
Refer to individual troubleshooting for those breakers.
Shut down ROWPU and reset the circuit breaker.
(a) Replace the circuit breaker if it does not stay set (para. 2-24).
(b) Refer to individual circuit troubleshooting for the breaker if it stays set with no power on the system.
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