Table 2-1. Direct Support Troubleshooting Guide (Continued)
TEST OR INSPECTION
5. Product high pressure light or horn does not work. (Ref. Schematic diagram FO-1, sheet 9, schematic lines 906-907 and
schemata diagram FO-1, sheet 10, schematic line 1012).
Refer to malfunctions 4 and 6 for additional troubleshooting procedures. Also, see light
test and alarm circuit troubleshooting.
Step 1. Shut down ROWPU and generator. Refer to electrical drawings in Appendix D and remove the wires from
A3X/A3Y and A2X/A2Y on relay K22. Check for continuity across each contact with the indicating plunger on
K22 (REF: Interconnection diagram FO-2, Sheet 6) out. Push the indicating plunger in and check that there is
no continuity across the contact. Normally open when plunger in.
If the continuity checks are not as noted above, replace relay K22 (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 wire (para. 2-20).
6. Product high pressure alarm is on and product pressure is less than 35 psig or alarm is not on and pressure is higher
than 45 psig.
Test product high pressure switch (PSH6) (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 water leakage. Set a multimeter 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 multimeter 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 39 to 41 psig.
(a) Replace the switch if there is internal leakage (para. 2-27).
(b) Adjust the switch to the correct setting if it does not actuate as described above. Remove the
adjustment cover and turn the adjuster clockwise to increase the actuation point, counterclockwise to
lower it (para. 2-29). If the switch is operating correctly, check the accuracy of the gauge which led to
(c) Replace the switch if it cannot be adjusted (para. 2-27).
7. Strainer high differential switch does not work. (Ref. Schematic diagram FO-1, sheet 9, lines 908-909).
This switch is factory set to open at 15 psig.
Refer to malfunctions 8 and 9 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 J24F (REF: Interconnection diagram FO-2, Sheet 14).
(a) Repair any loose or damaged wire (para. 2-18).
(b) Replace/repair connector J24 if faulty (para. 2-28).
(c) Replace PDSH1, if it shows an open circuit (para. 2-27).
Step 2. Shut down ROWPU and generator. Refer to electrical drawings in Appendix D and 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 K23(K2) (REF:
Interconnection diagram FO-2, Sheet 7). Remove the K1/K2 wires on K23 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).
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