Operating Trouble - Wilo Sub TWU 3 Notice De Montage Et De Mise En Service

8 Operating trouble

trouble
The pump fails to
start or stops
The pump fails to
deliver or the
discharge flow is too
small
Pump starts too
often
If the fault cannot be remedied, please contact wilo customer services.
cause
Incorrect voltage or voltage
d)
drop
Open circuit in motor power
e)
cable
c) The motor protection trips out
d) Voltage too low
e) Suction strainer clogged
f) Wrong direction of rotation
(tree-phase motor)
d) No water in borehole, or
level too low
d) Differential on pressure
sensitive switch too small.
e) Electrodes incorrectly placed.
f) The bladder vessel is too small or
is insufficiently pressurized.
ENGLISH
Remedial action
Check the voltage during startin; if
d)
the cable cross section is too small,
the voltage drop may such that the
motor cannot function normaly
Measure the resistance
e)
phases. Refit the pump if necessary
and check the cable
Check the current setting on the
f)
thermal relay and compare it to the
indicated value.
Important: Do not insist if the relay trips
out repetedly (try to locate the cause) ;
forced operation of the unit could damage
the motor (by overheating) in a very short
time (about a minute).
b) Check the supply voltage at the
box.
b) Refit the pump ; inclog and clean.
c) interchange two phase wires at the box.
d) Check the level ; it must be at least
0,20m above the pump discharge (with
pump running).
d) Increase the stop/start difference.
e) Adjust the distance between them so
that the timt between the stopping and
starting of the pump is reasonable.
f) Check and adjust the pressures
(on/off)
Check the pressure in the vessel.
Add a vessel to increase capacity or
change a lager vessel
Subject to technical alternatives !
between
19 (40)