Homa H 163 Series, Original Instruction Manual

Page: 15 / 40

15
10. Fault Finding Chart
Before maintenance or repair disconnect the pump
from the power supply to avoid accidental starting of the
pump!
Fault Cause Remedy
Motor does not start.
Fuses blow or motor
starter trips out im-
mediately.
Caution:
Do not start again!
•
Supply failure;
short-circuit; earth-
leakage; fault in
cable or motor
winding
•
Have the cable
and motor
checked and re-
paired by a quali-
fied electrician
•
Fuses blow due to
use of wrong type
of fuse
•
Install fuses of
the correct type
•
Impeller blocked by
impurities
•
Clean the impel-
ler and pump
housing
•
Level switch out of
adjustment or de-
fective
•
Check the level
switch
Pump operates, but
motor starter trips
out after a short
while •
Low setting of
thermal relay in mo-
tor starter
•
Set the relay in
accordance with
the specifications
on the pump label
•
Increased current
consumption due to
large voltage drop
•
Measure the volt-
age between two
motor phases.
Tolerance: ± 10%
(± 5% for explo-
sion-proof
pumps)
•
Impeller blocked by
impurities. In-
creased current
consumption in all
three phases
•
Clean the
impeller
Pump operates at
below-standard •
Impeller blocked by
impurities
•
Clean the
impeller
performance and
power consumption •
Wear of impeller
and suction cover
•
Adjust suction
cover again or
replace impeller
and suction cover
•
Wrong direction of
rotation (only 3 Ph-
pumps)
•
Check the direc-
tion of rotation
and possibly in-
terchange two
phases (see sec-
tion 6.4)
Pump operates, but
gives no liquid •
Discharge valve
closed or blocked
•
Check the dis-
charge valve and
possibly open
and/or clean
•
Non-return valve
blocked
•
Clean non-return
valve
•
Air in pump
•
Vent the pump