TM 10-4610-232-34
Table 2-1. Direct Support Troubleshooting Guide (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
8.
Step 17. Check resistance across the K10 coil (K1-K2). It should be close to zero.
(a) If the resistance is infinity or if it is zero, replace relay K10 (para. 2-23).
(b) If the resistance check on K10 is okay, replace relay LK1 (para. 2-23).
(c) Return the ROWPU to service and check operation of phase 1.
Step 18. Shut down ROWPU and generator. Refer to electrical drawings in Appendix D and remove wire #2A from
K11. Check continuity, point-to-point, from CB9 (wire #264) to relay K10(A1X). (Schematic line 704.) Depress
the indicating plunger on relay K2 during the test of its contact.
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace relay K2 if its contact is closed when the indicator plunger is out or if it is open when the
plunger is in (para. 2-23).
(c) Replace relay K15 if its contact is open (para. 2-23).
(d) Replace pressure switch PSL8 if it is open (para. 2-20).
Step 19. Check continuity, point-to-point, from relay K10(A1X) to relay K11(K1). Repeat the procedure from
transformer T1(X2) to relay K11 (wire #2A). Depress the indicating plunger on relays K10 and K2 when
checking their individual contacts. Remove wire #268 from PB16 before testing.
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace relay K10 if its contact is closed when the indicator plunger is out or if it is open when the
plunger is in (para. 2-23).
(c) Replace relay K2 if its contact is closed when the indicator plunger is out or if it is open when the
plunger is in (para. 2-23).
(d) Replace relay K11 if all the checks in steps 18-19 are okay (para. 2-23).
Backwash cycle phase 2. (Ref. Schematic diagram FO-1. sheet 7, schematic lines 721-729) (TDK2 setting 1 minute 36
seconds).
Step 1. Shutdown the ROWPU. Open the control panel. Restore power to the control panel, Turn off the raw water
pump circuit breaker CB4 and the boost pump circuit breaker CB5 (REF: Interconnection diagram FO-2,
Sheet 10). Disconnect the backwash chlorine pump, connector J45 (REF: Interconnection diagram FO-2,
Sheet 15). Set the control panel up in system “BACKWASH” and push “INITIATE”. Check that the indicating
plunger on relay K11 (REF: Interconnection diagram FO-2, Sheet 6) goes in at the end of phase 1 of the
backwash cycle.
If the plunger on K11 is not in, refer to backwash circuit phase 1 troubleshooting.
Step 2. Check that the inner pointer on time TDK2 (REF: Interconnection diagram FO-2, Sheet 8) is moving toward
zero.
If it is not moving, go to step 15.
Step 3. Remove connector J46 (REF: Interconnection diagram FO-2, Sheet 15) from the backwash air solenoid valve.
Check for 110-120 VAC across J46A and J46B.
If voltage is not present, go to step 5.
Step 4. Check P46 (REF: Interconnection diagram FO-2, Sheet 15) and the cable for damage.
(a) Replace/repair connector P46 if damaged (para. 2-18).
(b) Replace the backwash air solenoid valve SV6 (REF: Interconnection diagram FO-2, Sheet 15) if there
is no connector damage (para. 4-51 of TM 10-4610-232-12).
Step 5. Remove connector P16 (REF: Interconnection diagram FO-2, Sheet 15) from the control panel. Check for
110-120 VAC across J16N and J16P (REF: Interconnection diagram FO-2, Sheet 9).
If voltage is not present, go to step 13.
Step 6. Check for continuity and shorts from P16N to J46A and from P16P to J46B.
Replace/repair the connectors and cable as necessary (para. 2-18).
Step 7. Check that the indicating plunger on K13 (REF: Interconnection diagram FO-2, Sheet 6) is in.
If the plunger is out, go to step 12.
Step 8. Check for 110-120 VAC across J16D and J16E.
If voltage is not present, go to step 14.
Step 9. Reconnect J/P16 and check for 110-120 VAC at the chlorine backwash pump connector J45A and J45B.
If voltage is not present, go to step 11.
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Change 1
