Troubleshooting - caprari K+ Serie Betriebs- Und Wartungsanleitung

29. TROuBLEShOOTING

Faults
1. The electric pump fails to
start
2. The electric pump starts,
but the overload relay
activates.
3. The pump fails to give the
right head.
4. The pump fails to deliver
the correct flow rate.
caprari S.p.a.
K.M150N.. / K.M100N.. / K.W100N.. / K.d200N.. / K.M200P.. / K.d250P..
Probable causes
1.1. Motor not powered.
1.2. Selector switch in the OFF position.
1.3. Thermic relay activated.
1.4. The fuses have burnt out owing to an excessive
overload.
1.5. Phase missing.
1.6. The thermic probe circuit of the motor is open or the
connections have not been made correctly.
2.1. Full voltage is not reaching all phases of the motor.
2.2. The thermal relay value setting is too low.
2.3. Low/missing motor insulation.
2.4. Unbalanced power draw on the phases.
2.5. The impeller may be clogged, jammed or
damaged.
2.6. Pumped fluid excessively viscious and/or dense.
3.1. The intake or delivery sluice valve is partially
closed or clogged.
3.2. The check valve is partially clogged.
3.3. The intake/delivery pipe is clogged.
3.4. The pump turns in the wrong direction.
3.5. The pump head has diminished.
3.6. There are leaks from the system in the pumping
station.
4.1. The pump has become unprimed by an air pocket.
4.2. Clogged pump or pipes.
4.3. The minimum level gauge may have jammed in the
closed position.
4.4. Control selectors in the wrong position.
4.5. Possible wear on the wet side.
4.6. Sluice valve closed, or check valve blocked.
Remedies
1.1. Check whether the fuses have burnt out or
whether a circuit protecting relay has activated.
1.2. Select the ON position.
1.3. Identify and eliminate the causes. Check the
setting. Reset the thermic relay.
1.4. Identify the cause and replace the fuses.
1.5. Eliminate the cause. Check the line
connections.
1.6. Check that the thermal probe circuit is not broken,
or make the correct connections.
2.1. Check the condition of the fuses in the electrical
equipment.
2.2. Check the setting and correct it if necessary.
2.3. Switch off the motor power supply and check the
motor insulation.
2.4. Check the power draw on the phases. The
maximum unbalance must not exceed 5%. Having
ascertained an unbalance, contact a specialized
workshop.
2.5. If the previous inspections have failed to identify
the fault, remove the electric pump from the tank and
check whether the impeller has jammed.
2.6. Check whether the pump/motor combination is
correct.
3.1. Open or release the sluice valves.
3.2. Release the valve. If there is an external lever,
move this backwards and forwards several times.
3.3. Pump clear water to flush, or pump water at high
pressure through the pipes using a hose.
3.4. Electric pumps operating at low rotation speeds
may turn in the opposite direction with only a little
noise or vibration (particularly KCW models). Check
that the motor is turning in the right direction.
3.5. Check the total head with a pressure gauge when
the pump is operating. Compare the value with that
given in the instruction manual or, even better, with
a previous reading. If the pump has been in service
for some time and the head has dropped, remove the
pump and check for wear or if the impeller is clogged.
3.6. Check and repair any damage.
4.1. Switch off the electric pump for a few minutes
and then start it again.
4.2. Inspect the pump, pipes and tank in that order.
4.3. Check that the minimum level sensor is
unobstructed.
4.4. Set the selectors in the right positions.
4.5. Overhaul the pump.
4.6. Open the sluice valve or release the check
valve.
GB
33