Fault Finding; Disposal; Warning - Grundfos DW series Montage- Und Betriebsanleitung

9. Fault finding

Warning

Make sure that all power supplies have
been switched off and that all rotating
parts have stopped moving before
attempting to diagnose any fault.
Fault
1. Motor does not start. Fuses
blow or motor starter trips
immediately. Caution: Do not
start again!
2. Pump operates, but motor
starter trips after a short while.
3. Pump operates at
below-standard performance
and power consumption.
4. Pump operates, but gives no
liquid.

10. Disposal

This product or parts of it must be disposed of in an
environmentally sound way:
1. Use the public or private waste collection service.
2. If this is not possible, contact the nearest
Grundfos company or service workshop.
10
Cause
a) Supply failure; short-circuit;
earth-leakage fault in cable or
motor winding.
b) Fuses blow due to use of
wrong type of fuse.
c) Impeller blocked by impurities. Clean the impeller.
d) The electrodes are dirty or
defective.
a) Low setting of thermal relay in
motor starter.
b) Increased current
consumption due to large
voltage drop.
c) Impeller blocked by impurities.
Increased current
consumption in all three
phases.
d) For pumps running automatic
operation, the non-return
valve may be defective.
a) Impeller blocked by impurities.
b) Wrong direction of rotation.
c) The electrodes are dirty or
defective.
a) The electrodes are dirty or
defective.
Subject to alterations.
Remedy
Have the cable and motor checked
and repaired by a qualified
electrician.
Install fuses of the correct type.
Clean or replace the electrodes.
Set the relay in accordance with
the specifications on the
nameplate.
Measure the voltage between
motor phases. Tolerance: ± 10 %.
Clean the impeller.
Replace the non-return valve
Clean the impeller.
Check the direction of rotation and
possibly interchange two phases,
see section 7.1 Direction of
rotation.
Clean or replace the electrodes.
Clean or replace the electrodes.