Troubleshooting Chart - Grundfos SP Instrucciones De Instalación Y Funcionamiento

9.3 Troubleshooting chart

Problem Possible cause/how to check
1. Pump does a)
not run.
b)
c)
d)
e)
f)
g)
20
No power at pump control panel.
How to check:
Check for voltage at control
panel.
Fuses are blown or circuit
breakers are tripped.
How to check:
Remove fuses and check for
continuity with ohmmeter.
Motor starter overloads are burnt
or have tripped out (three-phase
only).
How to check:
Check for voltage on line or load
side of starter.
Starter does not energize
(three-phase only).
How to check:
Energize control circuit and check
for voltage at the holding coil.
Defective controls.
How to check:
Check all safety and pressure
switches for operation.
Inspect contacts in control
devices.
Motor and/or cable are defective.
How to check:
Turn off power. Disconnect motor
leads from control box.
Measure the lead-to-lead
resistances with the ohmmeter
(Rx1). Measure lead-to-ground
values with ohmmeter (Rx100K).
Record measured values.
Defective capacitor
(single-phase only).
How to check:
Turn off the power, then
discharge capacitor. Check with
an ohmmeter (Rx100K).
When meter is connected, the
needle should jump forward and
slowly drift back.
Possible remedy
If no voltage at control panel, check
feeder panel for tripped circuits.
Replace blown fuses or reset circuit
breaker. If new fuses blow or circuit
breaker trips, the electrical installation
and motor must be checked.
Replace burnt heaters or reset.
Inspect starter for other damage.
If heater trips again, check the supply
voltage and starter holding coil.
If no voltage, check control circuit.
If voltage, check holding coil for short
circuits. Replace bad coil.
Replace worn or defective parts.
If open motor winding or ground is
found, pull pump from the well and
recheck values at the surface.
Repair or replace motor or cable.
If there is no ohmmeter needle
movement, replace the capacitor.