TM 10-4610-232-34
Table 2-1. Direct Support Troubleshooting Guide (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Step 1. Shut down ROWPU and generator. Refer to electrical drawings in Appendix D. Remove the wires from
A3X/A3Y and A2X/A2Y on relay K21(REF: Interconnection diagram FO-2, Sheet 6). Check for continuity
across each contact with the indicating plunger of K21 out. Push the indicating plunger in and check that
there is no continuity across the contact.
If the continuity checks are not as noted above, replace relay K21(para. 2-23).
Step 2. Check the wires that were removed in step 1 for looseness or damage at their preceding connections.
Repair any loose or damaged wires (para. 2-20).
3. Feed high pressure alarm is on at less than 900 psig, or, is not on and system pressure Is more than 960 psig.
Test feed high pressure switch (PSH5) (REF: Interconnection diagram FO-2, Sheet 14) for accuracy. Disconnect P24
(REF: Interconnection diagram FO-2, Sheet 14) from the pressure switch panel. Disconnect the pressure sensing line
from the switch. Remove the cover on the switch and tag/remove the wires from the pressure switch. Check for
internal leakage, Set a multi meter to the Ohms x 1 scale and attach the leads to the switch terminals that the wires were
on. Connect a dead-weight tester or another known calibrated pressure control device to the switch pressure (or inlet)
port. The multi meter should read zero resistance with no pressure on the inlet pressure port. Slowly apply pressure to
the switch. The switch should open on an increasing pressure of 940 to 960 psig.
(a) Replace the switch if there is internal leakage (para. 2-27).
(b) Replace the switch if testing indicates it is actuating outside of the listed limits above (para. 2-27).
(c) Refer to pressure gauge troubleshooting if the switch is actuating within the listed limits above.
4. Product high pressure switch does not work. (Ref. Schematic diagram FO-1, sheet 9, schematic lines 905-906).
NOTE
This switch is factory set to open at 40 psig.
NOTE
Refer to malfunctions 5 and 6 for further troubleshooting procedures.
Step 1. Shutdown ROWPU and generator. Refer to the electrical schematic Appendix D. Check continuity, point-to-
point, from J24A to J24E (REF: Interconnection diagram FO-2, Sheet 14).
(a) Repair any damaged or loose wires (para. 2-28).
(b) Replace/repair connector J24 if faulty (para. 2-28).
(c) Replace PSH6 (REF: Interconnection diagram FO-2, Sheet 14), if it shows an open circuit (para, 2-27).
Step 2. Shut down ROWPU and generator. Refer to electrical drawings in Appendix D. Check continuity, point-to-
point, from transformer T1(X1) (REF: Interconnection diagram FO-2, Sheet 10) to J11A (REF: Interconnection
diagram FO-2, Sheet 9). Repeat the procedure from T1(X2) to relay K22(K2) (REF: Interconnection diagram
FO-2, Sheet 6). Remove the K1/K2 wires on K22 before testing.
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace circuit breaker CB7 or CB10 (REF: Interconnection diagram FO-2, Sheet 8) if either is open
(para. 2-23). Normally closed.
(c) Replace emergency stop PB3 (REF: Interconnection diagram FO-2, Sheet 11) if open (para. 2-22).
(d) Replace/repair connector J11 if faulty (para. 2-21).
Step 3. Check continuity, point-to-point, from J11E to K22(K1). Depress the indicating plungers on K6 (REF:
Interconnection diagram FO-2, Sheet 7) and K22 when testing continuity across their contacts.
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace/repair connector J11 if faulty (para. 2-21).
(c) Replace relay K6 or K22 if their set of contacts does not show continuity when the indicating plunger is
depressed (para. 2-23).
(d) Replace relay K22 if all the continuity checks are good (para. 2-23).
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