English (GB)
19
10.1 Megging
Megging of an installation incorporating SQ/SQE
pumps is not allowed, as the built-in electronics may
be damaged. See fig. 13.
Fig. 13
3.
The pump runs at
reduced capacity.
a)
The drawdown is larger than
anticipated.
Increase the installation depth of the pump,
throttle the pump or replace it by a smaller
model to obtain a smaller capacity.
b)
The valves in the discharge pipe
are partly closed/blocked.
Check and clean/replace the valves,
if necessary.
c)
The discharge pipe is partly
choked by impurities (ochre).
Clean/replace the discharge pipe.
d)
The non-return valve of the pump
is partly blocked.
Pull out the pump and check/replace the
valve.
e)
The pump and the riser pipe are
partly choked by impurities
(ochre).
Pull out the pump. Check and clean or
replace the pump, if necessary. Clean the
pipes.
f)
The pump is defective.
Repair/replace the pump.
g)
Leakage in the pipework.
Check and repair the pipework.
h)
The riser pipe is defective.
Replace the riser pipe.
i)
Undervoltage has occurred.
Check the power supply.
4.
Frequent starts
and stops.
a)
The differential of the pressure
switch between the start and stop
pressures is too small.
Increase the differential. However, the stop
pressure must not exceed the operating
pressure of the pressure tank, and the start
pressure should be high enough to ensure
sufficient water supply.
b)
The water level electrodes or level
switches in the reservoir have not
been installed correctly.
Adjust the intervals of the electrodes/level
switches to ensure suitable time between
the cutting-in and cutting-out of the pump.
See installation and operating instructions
for the automatic devices used. If the
intervals between stop/start cannot be
changed via the automatics, the pump
capacity may be reduced by throttling the
discharge valve.
c)
The non-return valve is leaking or
stuck half-open.
Pull out the pump and clean/replace the
non-return valve.
d)
The supply voltage is unstable.
Check the power supply.
e)
The motor temperature gets too
high.
Check the water temperature.
Fault Cause
Remedy
T
M
02
06
89
50
0
0
C
C
U
U
U
PE
N
L
C
C
