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Installation and operating instructions -MVI 5, 15, 20, 50, 75, 100, 160, 225, 320, 450, 600, 750
Faults
Possible causes
Remedies
Pump does not run when the motor starter is
activated.
Supply failure or no power supply.
Check connections or restart the power
supply.
Main contacts in motor starter are not
making contact or the motor coils are
defective.
Reconnect or replace contacts or
magnetic coil.
Pump or auxiliary circuit protection fuses
blown.
Replace fuses.
Pump or piping system may be
obstructed causing a jam.
Clear the obstruction and restart pump.
Motor may have failed.
Replace the motor.
Motor protector or thermal relay has
tripped out.
Reset the motor or thermal protector.
Tripping of anti-dry running protection
(Provided by others).
Check the water level in the tank or the
water system pressure. If everything is in
order, check the protection device and its
connection cables.
Starter overload trips immediately when the power
is switched on.
Overload setting is too low.
Set the motor starter correctly.
The cable connection is loose or faulty.
Fasten or replace the cable connection.
Fuse is blown.
Replace fuse and try starting again.
Pump is jammed by an obstruction.
Check and clean obstruction from
system.
Contacts in overload are faulty.
Replace motor starter contacts.
The motor winding is defective.
Replace the motor.
Low voltage (Especially at peak time).
Check the power supply.
The pump starts but, after a short time, the thermal
protector trips out or the fuses blow.
The voltage is not within the motor’s
operating limits.
Check the operating conditions of the
pump.
The control panel is situated in an
excessively heated area or is exposed to
direct sunlight.
Protect the control panel from heat
sources and from the
sun.
A phase in the power supply is missing.
Check the power supply.
The pump starts up but, after a period of time, the
thermal protector trips.
Worn motor bearings causing motor to
overheat.
Replace motor bearings.
The pump’s delivery rate is higher
than the specified rate on the pump
nameplate.
Partially close the on-off valve located
discharge side until the delivery rate
returns to within the specified limits.
There are obstructions inside the pump
or pumping system.
Disassemble and clean the pump and
piping.
Less viscous liquids may cause the motor
to work too hard and overload the motor,
causing the motor to overheat.
Check the actual power requirements
based on the characteristics of the liquid
being pumped, and replace the
motor accordingly.
10. Faults, causes and remedies
WARNING! Electrical shock hazard!
Step 9:
Cross tighten the allen screws holding the
seal to the shaft to six ft-lbs. torque.
Step 10:
Lift the pump shaft and insert the shaft
spacer under the seal flange.
Step 11:
Install the coupling with the bottom
portion sitting on the top of the shaft spacer.
Install allen screws and loosely tighten all four of
them.
