Fault Finding The Product - Grundfos CR 95 Installation And Operating Instructions Manual

8. Fault finding the product

DANGER
Electric shock
Death or serious personal injury
- Before starting any work on the product,
make sure that the power supply has
been switched off and that it cannot be
accidentally switched on.
WARNING
Corrosive liquids
Death or serious personal injury
- Wear personal protective equipment.
WARNING
Toxic liquids
Death or serious personal injury
- Wear personal protective equipment.
Fault
1. The motor does not
run when started.
2. The motor-protective
circuit breaker trips
immediately when the
power supply is
switched on.
3. The motor-protective
circuit breaker trips
occasionally.
4. The motor-protective
circuit breaker has
not tripped, but the
pump does not run.
20
Cause
a) Supply failure.
b) The fuses are blown.
c) The motor-protective circuit breaker
has tripped.
d) The thermal protection has tripped.
e) The main contacts in the motor-
protective circuit breaker are not
making contact or the coil is faulty.
f) The control circuit is defective.
g) The motor is defective.
a) One fuse is blown or the automatic
circuit breaker has tripped.
b) The contacts in the motor-protective
circuit breaker are faulty.
c) The cable connection is loose or
faulty.
d) The motor winding is defective.
e) The pump is mechanically blocked.
f) The motor-protective circuit breaker
setting is too low.
a) The motor-protective circuit breaker
setting is too low.
b) Low voltage at peak times.
a) Check 1a, 1b, 1d, 1e and 1f.
WARNING
Falling objects
Death or serious personal injury
- Keep the product in a stable and fixed
position when working on it.
CAUTION
Hot or cold liquid
Minor or moderate personal injury
- Wear personal protective equipment.
CAUTION
Hot or cold surface
Minor or moderate personal injury
- Make sure that no one can accidentally
come into contact with hot or cold
surfaces.
Remedy
Connect the power supply.
Replace the fuses.
Reactivate the motor-protective
circuit breaker.
Reactivate the thermal protection.
Replace the contacts or the
magnetic coil.
Repair the control circuit.
Replace the motor.
Replace the fuse or cut in the
circuit breaker.
Replace the motor-protective circuit
breaker contacts.
Fasten or replace the cable
connection.
Replace the motor.
Remove the mechanical blocking of
the pump.
Set the motor-protective circuit
breaker correctly.
Set the motor-protective circuit
breaker correctly.
Ensure a stable power supply.