English (GB)
25
9. Fault finding the product
Before attempting to diagnose any fault, read and
observe the safety instructions in section 8.1 Safety
instructions and requirements.
Observe all regulations applying to pumps
installed in potentially explosive
environments.
Make sure that no work is carried out in
potentially explosive atmosphere.
Before attempting to diagnose any fault,
- make sure that the fuses have been
removed or the main switch has been
switched off
- make sure that the power supply cannot
be accidentally switched on
- make sure all rotating parts have
stopped moving.
Fault Cause Remedy
1. The pump does not start.
The fuses blow, or the
motor-protective circuit
breaker trips immediately.
Caution: Do not start again!
a) Power supply failure, short
circuit or earth leakage in the
power cable or the motor
windings.
Have the power cable and motor
checked and repaired by a qualified
electrician.
b) Wrong type of fuse. Install fuses of the correct type.
c) The impeller is blocked by
impurities.
Clean the impeller.
d) The air bells, the float switches
or the electrodes are out of
adjustment or defective.
Readjust or replace the air bells,
float switches or electrodes.
2. The pump starts, but the
motor-protective circuit
breaker trips after a short
while.
a) Low setting of the thermal relay
in the motor-protective circuit
breaker.
Set the relay in accordance with the
specifications on the nameplate.
b) Increased current consumption
due to large voltage drop.
Measure the voltage between two
motor phases.
Tolerance: - 10 %/+ 6 %.
Reestablish correct voltage supply.
c) The impeller is blocked by
impurities. Increased current
consumption in all three
phases.
Clean the impeller.
d) The impeller clearance is
incorrect.
Readjust the impeller.
See section 8.5 Adjusting the
impeller clearance, fig. 12.
3. The pump's thermal switch
trips when the pump has
been running for some time.
a) The liquid temperature is too
high.
Reduce the liquid temperature.
b) The liquid viscosity is too high. Dilute the liquid.
c) Wrong electrical connection. (If
the pump is star-connected to a
delta connection, the result will
be very low undervoltage).
Check and correct the electrical
installation.
4. The pump operates at
below-standard
performance and increased
power consumption.
a) The impeller is blocked by
impurities.
Clean the impeller.
b) The direction of rotation is
wrong.
Check the direction of rotation. If it
is not correct, interchange two
phases in the power cable. See
section 4.3 Direction of rotation.
5. The pump operates but
delivers no liquid.
a) The outlet valve is closed or
blocked.
Check the outlet valve and open
and/or clean it, if necessary.
b) The non-return valve is
blocked.
Clean the non-return valve.
c) There is air in the pump. Vent the pump.
6. The pump is blocked. a) The grinder system is worn. Replace the grinder system.
To Next Page
Loading...
Need help?
General
