Wilo -FireSet UL FM Notice De Montage Et De Mise En Service page 60

Faults
Pumps not ready for operation sud -
denly started
Presence of voltage on motor
housing
Unusual overheating of motor's
exterior
Main pump starts before jockey
pump
Main pump starts immediately, with
inhibition indicator in position 1
Sudden speed drop
Magnetic noise, sudden whistling
Mechanical noise
Pump/motor bearings overheating
Unusual vibrations
Motor does not stop after using
stop button
Installation and operating instructions Wilo-FireSet UL FM
Causes
Incorrect sizing of power line
Insufficient voltage
Pump sizing
Contact between live conductor and
earth
Humid or old Insulation
Short-circuit between terminals and
external housing
Pump overload
Coupling out of axis
Ambient temperature higher than 40°C
Voltage higher/lower than nominal
value
Phase failure
Insufficient ventilation
Sliding between stator and rotor
Unbalanced voltage on three-phases
Pressure switch on main pump cali -
brated at a higher value than the jockey
pump
Pressure switch calibrated at a lower
value than the system pressure
Water level in priming tank too low
Instantaneous overload/foreign part in
pump
Single-phase operation
Voltage drop
Motor winding or short-circuit
Friction between stator and rotor
Loosened bolts
Loosened screws in fan cover cap/cou -
pling cover cap
Sliding between fan and motor, and
between coupling and coupling cover
cap, etc.
Foreign parts in motor or pump
Coupling not aligned
Bearings little oiled/worn/broken
Bearings damaged
Insufficient lubrication
Pump and motor not aligned
No vibration-damping sleeve devices
on the unit
Pump in cavitation
Too much air in water
Bearings, pump /motor shaft worn
Pump/motor coupling are worn
Pump and motor not aligned
This is normal if the system pressure is
not restored
Switchgear failure
Electromagnet for stopping diesel
pump switchgear failure
Remedies
Check and replace.
Check power supply.
Remove the rotating parts, then check the siz -
ing.
Correct connections.
Dry the motor or rewind it.
Check insulation between terminals and hous -
ing.
Dismantle and check.
Align correctly.
Ventilate the space.
Check upstream power supply.
Check power supply and fuses.
Check strainers and pipes. Resize.
Repair or change the motor.
Check power supply.
Check pressure switch settings.
Check pressure switch settings.
Increase the pressure level in the installation.
Check level of priming tank.
Dismantle the pump.
Check supply and fuses
Check supply
Dismantle the motor, then repair or change it.
Dismantle the motor, then repair or change it.
Check and tighten them.
Check and tighten them.
Ensure the correct distance and reassemble.
Dismantle and remove.
Realign.
Lubricate or replace them.
Replace them.
Lubricate again.
Realign.
Install or repair them.
Review the sizing of the installation.
Make sure that there are no leaks in the suction
line. Check the distance between the suction
points if several pumps have been installed. Fit
anti-vortex plates.
Replace.
Replace.
Realign pump and motor.
Stop the automatic mode, then stop the pump.
Turn off the switchgear, then check.
Use the fuel lever on which the electromagnet
works manually
English
19