TM 10-4610-241-24
TO 40W4-13-42
Table 3-1. Direct Support Troubleshooting - continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
BACKWASH PUMP ASSEMBLY - continued
WARNING
High voltages in this equipment can cause serious injury or death. When applying power
during a test, take proper measures to ensure safety of personnel. Never work on
electrical equipment unless there is another person nearby who is familiar with the
operation and hazards of the equipment.
Step 6. Disconnect pump cable assembly at backwash pump motor and check it for continuity.
a.
If continuity exists, repair centrifugal pump. Refer to Paragraph 3-8.
b.
If continuity does not exist, repair pump cable assembly. Refer to Paragraph 3-7.
Step 7. Remove power at power source and check for continuity through control circuits as follows. Make
additional point-to-point checks as necessary to isolate fault to a specific component.
NOTE
To measure continuity through K6 contacts, it is necessary to close contacts by
physically raising handles on side of relay.
CB1
-
J8(P)
J9(P)
-
J9(D) and (W)
P9(W)
-
P8(W)
P9(D)
-
P8(D)
P9(P)
-
P8(P)
J8(D)
-
K2(2)
J8(W)
-
K2(3)
K2(2)
-
K2(A2) (See above note)
K2(A1)
-
K2(A2) (Required value is 90-120 ohms)
J1(N)
-
K2(A1)
a.
If switch S13 or S3 is open (switches ON), replace it. Refer to Paragraph 3-49.
b.
If continuity does not exist through CB9 (CB9 ON), replace CB9. 'Refer to Paragraph 3-53.
c.
If continuity does not exist through heater assembly, replace defective heaters (Paragraph 3-61) and
reset heater assembly.
3-80
