Pentair P42B0007A2-01, Electronic Manual

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SECTION 13: Troubleshooting
Pump And Motor Problem Analysis (Continued)
Problem Possible Cause Check And Restore
Pu mp runs all the
time (continued)
Pump wear. 1. Check amperage - generally lower unless severe bearing damage has
occurred.
2. Verification may require removal of pump for service and visual
inspection.
Electric shock. Gr ounded wiring
or motor.
1. PROCEED WITH CAUTION!
2. Remove rings and other jewelry from hands before working with live
power circuits.
3. Wear insulated boots and gloves.
4. Disconnect the power, check with ohmmeter.
5. Progressively check wire at each splice point (or obvious damage
point).
6. When ground disappears, the fault is behind the point of discovery.
7. Check motor leads to motor shell with cable splice removed to
determine if ground fault is in motor or supply cable.
Moisture. Protect motor, motor starter and control devices from condensation or
direct water spray.
Am meter reads high
on two leads, zero
on the 3rd.
Th ree phase
motor “single
phasing”.
1. One power lead is not live or online.
2. Check with local utility company to see if having problems.
3. Check local power installation for transformer problems.
4. Will not be able to observe this condition very long. Very destructive to
motor windings. Motor stator will soon be destroyed if single phasing
protection is not installed.
5. This problem usually requires a replacement motor.
6. Determine source, install or replace protective gear.
Ov erload trip –
ammeter reads high
on all leads.
Bi nding or
dragging.
1. High volume of sand or other abrasives in well. Check by observing
water output.
2. Severe damage to motor thrust bearing due to cavitation or abrasives.
Usually very noisy.
3. Damage to motor control system.
Po wer supply
problems.
1. Check with voltmeter while pump is running for ±10% voltage
variance.
2. Extreme grounding of motor or supply cable. Check with ohmmeter
or megohmmeter.
3. Poor wiring connections. Check splice, and terminal screws for
looseness. Watch for discolored cable.
Troubleshooting