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EVMS/EVMSL
８ Troubleshooting
Trouble
The motor is damaged.
Power supply abnormality.
Motor won't turn.
Motor growls and
Rotating parts in contact. Rust. Burning.
won't turn
Foreign material caught in the contacting surfaces.
Pump not primed.
Gate valve is closed or half open.
Reverse rotation direction.
Pump speed too low.
* Motor has wrong number of poles.
* 60 Hz pump used in 50 Hz power supply area.
* Voltage drop has occurred.
Impeller is clogged with foreign matter.
Piping is clogged with foreign matter.
Foot valve and/or strainer is clogged with foreign
Pump operates,
but no water is
matter.
discharged.
Air is being sucked in.
Water is not
Foot valve or end of suction piping is not properly
discharged at the
submerged in the water.
rated capacity.
Leakage from discharge piping.
Impeller is corroded.
Impeller is worn.
Wear ring is worn.
Large loss in the piping.
Suction head is too high for the pump.
Discharge head is too high for the pump.
High fluid temperature or volatile fluid.
Cavitation.
Not primed sufficiently.
Water is
Air is being sucked in.
discharged,
Air is trapped inside the suction piping.
but stops.
Suction head is too high for the pump.
Voltage has dropped or phase imbalance is large.
* Head is low. Too much water flow.
* 50 Hz pump in a 60 Hz region.
Overload (over
Head is too low. Discharge capacity is too high.
current) occurs.
Bearing is damaged.
Rotating parts in contact. Shaft is bent.
Fluid specific gravity, viscosity is too great.
Bearing is damaged.
Bearing heats up
Pump is operated for prolonged period at shut-off
pressure.
Bearing is damaged.
Discharge capacity is too high.
Impeller is clogged with foreign matter.
Pump vibrates.
Reverse rotation direction.
Loud operation
Pump is operated for prolonged period at shut-off
noise.
pressure.
Rotating parts in contact. Shaft is bent.
Cavitation.
Piping vibrates.
Mechanical seal is damaged.
More leakage from
the shaft seal.
Suction pressure is too high.
Cause
- 20 -
Remedy
Repair the motor.
Inspect and repair.
Manually rotate. Re-assemble. Have repaired by a
specialist workshop.
Remove the foreign material.
Prime the pump.
Open the gate valve.
Check the rotation arrow, and correct the wiring.
* Consult nameplate data and replace motor with
correct one.
* Consult nameplate data and replace correct pump.
* Check the power supply.
Remove the foreign material.
Remove the foreign material.
Remove the foreign material.
Inspect, repair suction piping and shaft seal.
Extend suction piping so that foot valve / end of
piping to be submerged at least 2 times deeper than
the diameter of the piping.
Inspect, repair.
Check the fluid, change material.
Replace the impeller.
Replace wear ring.
Review the plan.
Review the plan.
Review the plan.
Consult with EBARA.
Sufficiently prime the pump.
Inspect, repair suction piping and shaft seal.
Refit the piping.
Review the plan.
* Consult nameplate and replace motor with correct
one.
* Consult nameplate and replace correct pump.
Turn down discharge valve to adjust to prescribed
capacity.
Replace bearing.
Consult with EBARA.
Review the plan.
Replace bearing.
Stop shut-off pressure operation.
Replace bearing.
Turn down discharge valve to adjust to prescribed
capacity.
Remove the foreign material.
Check the rotation arrow, and correct the wiring.
Stop shut-off pressure operation.
Consult with EBARA.
Consult with EBARA.
Rectify the piping.
Replace mechanical seal.
Review the plan.
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