Troubleshooting - EBARA DL Instruction Manual

8

Troubleshooting

Trouble
Pump does not - Float movement is obstructed.
start, or starts - Power failure has occurred.
but immediately
stops.
- 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.
Operates, but - Prolonged dry operation has activated automatic
stops after a cut-off function.
while. - High liquid temperature has activated automatic
cut-off function.
Thermal - Liquid temperature is high.
protector - Pump is run in air for prolong time.
activates. - Overcurrent
Flood-sensing - Mechanical seal leaks.
device
activates.
- No longer serviceable.
Pumping not - Pump running in reverse rotation.
effected, or - Gate valve is damaged.
insufficient - Excessive voltage drop.
pumping - 60 Hz pump used with 50 Hz.
capacity. - 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.
Overcurrent - Excessive voltage imbalance between supply
occurs. 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.
Vibration - Pump running in reverse rotation.
excessive or - Foreign matter trapped in pump.
noise. - Piping resonating.
Cause
- Excessive imbalance in power supply
voltage.
- 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.
- Raise stop water level.
- Lower liquid temperature.
- Lower liquid temperature.
- Raise stop water level.
- Refer to the column for overcurrent.
- Replace the mechanical seal.
(Liquid quality and operation conditions need to
be reviewed.)
- Replace the mechanical seal.
- 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).
- 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.
- Obtain regular rotation (Refer to ６ -2. (2)).
- Disassemble pump and eliminate foreign matter.
- Make improvements in piping to stop resonance.
- 17 -
Remedy
EBARA
CORPORATION
.