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10 Causes for malfunctioning
Problems
Probable causes
Remedies
1. The electropump does not
start
1.1. The selector switch is set to the OFF position.
1.2. The motor is not powered.
1.3. The automatic control devices (level gauge,
etc.) are not enabling the equipment.
1.1. Turn to the ON position.
1.2. Check if the fuses have burnt out or if the circuit
protecting relay has activated.
Check tightness of the terminals.
Check if the equipment is receiving power.
1.3. Wait for the operating conditions to be restored or
check the efficiency of the monitoring devices.
2. The fuses blow at start up.
2.1. Fuses of inadequate size.
2.2. Unit rotor jammed.
2.3. Damaged power supply cable or junction
(short circuit).
2.4. Insufficient electrical insulation
2.1. Replace with fuses suited to the power draw of the
motor.
2.2. Send the unit to the authorised assistance centre.
2.3. Change the cable or repeat the connection.
2.4. Use an ohmmeter to check the insulation resistance
according to the values given in chapter 5.5. If
necessary contact the authorized service centre.
3. The overload relay trips after
just a few seconds of
working.
3.1. Full voltage is not reaching all motor phases.
3.2. Current absorption is unbalanced with at least
one phase with current higher than the rated
value.
3.3. Current absorption is abnormal.
3.4. Relays set incorrectly.
3.5. Unit rotor jammed.
3.6. The supply voltage does not correspond to
that of the motor.
3.1. Check integrity of the electrical equipment.
Check tightness of the terminal block.
Check power supply voltage.
3.2. Check the unbalance on the phases according to the
procedure given in paragraph 7.2 “Starting the
motor”. If necessary send the motor to the authorised
service centre.
3.3. Check accuracy of the star or delta connections.
3.4. Check that the setting amperage is correct
3.5. Send the unit to the authorized service centre.
3.6. Change the motor or power supply.
4. The overload relay trips after
just a few minutes of
working.
4.1. Relay set incorrectly.
4.2. Mains voltage is too low.
4.3. Current absorption is abnormal on the phases
with a value higher than the nominal value.
4.4. The electropump is not turning freely due to
friction points.
4.5. The electropump fails to turn freely due to high
sand content.
4.6 The electropump is locked.
4.6. Electrical panel temperature high.
4.1. See 3.4.
4.2. Contact the Electricity Board.
4.3. See 3.2.
4.4. Send the motor to the authorised assistance centre.
4.5. Reduce the flow rate by means of the sluice valve
4.6. Send the pump to the authorized service centre.
4.6. Protect the electrical control panel from the sun and
heat sources.
5. The electric pump delivers at
a decidedly poor flow rate.
5.1. The motor turns in the wrong direction.
5.2. Air intaken from the suction mouth or pump
operating in cavitation conditions.
5.3. The check valve is blocked in a partially closed
position.
5.4. Worn electropump.
5.5. Water exits from delivery pipes.
5.6. Suction chamber locked due to material inside
the well.
5.1. Invert two of the three phases
5.2. Increase the delivery bowl head.
5.3. Disconnect the pump from the pipe and check. Send
the pump to an authorized service centre if necessary.
5.4. Send the pump to an authorized service centre.
5.5. Check the pipes are ok and the flange seals are
installed and well clamped.
5.6. Clean the pump
6. Although it operates, the
electric pump delivers
absolutely no water
6.1. Pump unprimed owing to insufficient head.
6.2. The check valve has blocked in the closed
position.
6.3. Closed sluice valve.
6.4. Excessively worn electropump.
6.1. See point 5.2.
6.2. See point 5.3.
6.3. Adjust the sluice valve
6.4. See point 5.4.
7. The electropump is too noisy
and vibrates
7.1. Incorrect rotating sense.
7.2. Plant installed incorrectly.
7.3. Water containing a high amount of gas.
7.4. worn shaft and guide bearing
7.1. See point 5.1.
7.2. See point 5.2.
7.3. See point 5.2.
7.4. See point 5.4.
EN
