Fault Finding Chart; Bmp Hp Feed Pump - Grundfos BMPX Serie Instrucciones De Instalación Y Funcionamiento

18. Fault finding chart

18.1 BMP hp feed pump

Warning
Before starting work on the BMP hp feed pump, make sure that the electricity supply has been switched off and that
it cannot be accidentally switched on.
Fault Cause
1. The pump stops during a) No water supply.
operation.
2. The pump does not run. a) The fuses are blown.
b) The motor starter overload unit has tripped
c) The magnetic coil in the motor starter/
d) The control circuit has cut out or is defective. Check the control circuit and the contacts in the
e) The motor/supply cable is defective.
3. The pump runs, but a) No or insufficient water supply at the pump
gives no water nor
develops any pressure.
b) The piping system or pump is choked up.
c) The prefilter is clogged.
d) The pump is worn.
e) Wrong direction of rotation.
4. The pump runs at a) The pump is partly blocked by impurities.
reduced capacity.
b) The pump is defective.
c) The prefilter is clogged.
d) The motor speed is too low.
12
The low-pressure switch has cut out.
The level switch has cut out.
out.
contactor is defective (not cutting in).
suction port.
Remedy
Check that the low-pressure switch functions normally
and is adjusted correctly.
Check that the minimum inlet pressure is correct. If not,
check the feed pump.
Check the water level in the water tank.
After a cut-out, the cause of a possible short-circuit
must be found.
If the fuses are blown, check whether the motor starter
has been set correctly or is faulty.
If the fuses are hot when they are replaced, check that
the load of the individual phases does not exceed the
motor current during operation. Identify the cause of the
load.
If the fuses are not hot immediately after the cut-out, the
cause of a possible short-circuit must be identified.
Possible fuses in the control circuit must be checked
and defective fuses must be replaced.
Reset the starter overload. See also sections
9.2.2 Motor protection and 11. Start-up and operation.
Replace the coil. Check the coil voltage.
monitoring devices (low-pressure switch, level switch,
etc.).
Check motor and cable. See section 9. Electrical
connection.
Check that the inlet pressure during operation is at least
0 bar. See section 5. Technical data.
Restart the pump as described in section 11. Start-up
and operation.
Check the piping system and pump.
Clean the prefilter.
Replace the wear parts. Contact Grundfos Service.
See section 11. Start-up and operation.
Dismantle, clean and check the pump.
Replace defective parts. Contact Grundfos Service.
Replace defective parts. Contact Grundfos Service.
Clean the prefilter.
Check the electricity supply.
Contact the electricity supply authorities, if necessary.
If a frequency converter is used, adjust the speed.