EBARA DL - Troubleshooting

EBARA
CORPORATION
.
- 17 -
8
Troubleshooting
Trouble
Cause
Remedy
Pump does not
start, or starts
but immediately
stops.
- Float movement is obstructed.
- Power failure has occurred.
- Excessive imbalance in power supply
voltage.
- Excessive voltage drop.
- Phase interruption.
- Faulty connection in power circuits.
- Error in control circuit wiring.
- Blown fuse.
- Faulty magnet switch.
- Level switches are malfunctioning or faulty.
- Electrical leakage breaker activated.
- Foreign matter trapped in pump.
- Motor burned out.
- Motor bearings worn out.
- Mechanical seal locked.
- Remove the obstructions.
- Contact electric power company.
- Contact electric power company.
- Contact electric power company.
- Check wiring connections and magnetic switch.
- Check power circuits.
- Correct wiring error.
- Replace with fuse of correct capacity.
- Replace with item of correct specification.
- Replace or repair.
- Perform repair at location of leakage.
- Eliminate foreign matter.
- Replace or repair.
- Replace or repair.
- Replace or repair.
Operates, but
stops after a
while.
- Prolonged dry operation has activated automatic
cut-off function.
- High liquid temperature has activated automatic
cut-off function.
- Raise stop water level.
- Lower liquid temperature.
Thermal
protector
activates.
- Liquid temperature is high.
- Pump is run in air for prolong time.
- Overcurrent
- Lower liquid temperature.
- Raise stop water level.
- Refer to the column for overcurrent.
Flood-sensing
device
activates.
- Mechanical seal leaks.
- No longer serviceable.
- Replace the mechanical seal.
(Liquid quality and operation conditions need to
be reviewed.)
- Replace the mechanical seal.
Pumping not
effected, or
insufficient
pumping
capacity.
- Pump running in reverse rotation.
- Gate valve is damaged.
- Excessive voltage drop.
- 60 Hz pump used with 50 Hz.
- Discharge head too high.
- Piping loss too large.
- Water level too low, air drawn in.
- Discharge pipe leaking.
- Discharge pipe clogged.
- Foreign matter in suction inlet.
- Pump interior clogged with foreign matter.
- Impeller(s) worn out.
- Obtain regular rotation (Refer to ６ -2. (2)).
- Inspect and repair.
- Contac electric power company.
- See nameplate for frequency.
- Rethink system plan.
- Rethink system plan.
- Raise water level or lower pump’s position.
- Inspect and repair.
- Unclog pipe.
- Remove foreign matter.
- Disassemble pump and eliminate foreign matter.
- Replace impeller(s).
Overcurrent
occurs.
- Excessive voltage imbalance between supply
phases.
- Excessive voltage drop.
- Phase interruption.
- 50 Hz pump used with 60 Hz.
- Pump running in reverse rotation.
- Head too low. Water flow rate too high.
- Foreign matter trapped in pump.
- Motor bearing worn out.
- Contact electric power company.
- Contact electric power company.
- Check connections and magnet switch.
- See nameplate for frequency.
- Obtain regular rotation (Refer to ６ -2. (2)).
- Turn down the gate valve. If there is no gate
valve, replace the pump with the lower head
pump.
- Disassemble pump and eliminate foreign matter.
- Replace or repair.
Vibration
excessive or
noise.
- Pump running in reverse rotation.
- Foreign matter trapped in pump.
- Piping resonating.
- Obtain regular rotation (Refer to ６ -2. (2)).
- Disassemble pump and eliminate foreign matter.
- Make improvements in piping to stop resonance.