Wilo Wilo-SiFire FIRST, Инструкция по установке и эксплуатации

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Faults, causes and remedies en
Installation and operating instructions Wilo-SiFire FIRST 75
standing the instructions in this manual. Never attempt to repair materials or equip-
ment without fully understanding its operation.
If personnel do not have sufficient knowledge of the product and the operating logic
required by the specific regulations for fire-fighting systems, or if they do not have the
necessary technical skills, contact Wilo for regular maintenance checks.
MAIN ELECTRIC PUMP
FAULT CAUSE REMEDIES
The motor does not start
Missing power supply Check the connections and the electrical panel
Short-circuit in the windings Check the windings in the workshop
Overload Check the sizing of the power supply line. Check that the
pump is not blocked
Switchgear failure/incorrect connec-
tions Check connections
Incorrect direction of rotation Reverse two feeding phases
Suction depth too high. Pump cavita-
tion Review calculations based on NPSHr value from pump
The pump, while operating, does not
deliver water or has a very low flow
rate/ delivery head. Piping and suction valves of unsuit-
able diameter. Pump cavitation Review calculations based on NPSHr value from pump
Air entering the suction line Check that there are no leakages in the suction line.
Check the distance between the suction units. If more
than one pump is installed, install anti-vortex plates
Partially/totally closed shut-off valves Open the suction and discharge valves
Worn pump Check and repair
Pump impeller blocked Check and repair
Suction strainer/clogged filters Check and repair
Worn pump and motor joint Check and repair
The motor does not reach the rated
speed See next item
Voltage too low at the ends of the
motor Check supply voltage, connections and cable cross-sec-
tions on the supply line
The motor does not reach the rated
speed Bad contacts in the power contactor
or starting device failure Check and repair
Phase failure Check line, connection and fuses
Uncertain contact in power cables Check the tightening of the terminals
Earthing or short-circuit at winding Dismantle the motor and have it repaired at the factory
Inability to operate under load after
start-up Insufficient sizing of the switch and
fuses of the power supply line Resize and replace
Insufficient voltage Check the power supply
Pump blocked Remove the rotating part and check
Presence of voltage on the motor
housing Exchange between line and ground
cables Correct connections
Wet or aged insulation Dry the motor or rewind it
Short-circuit between terminals and
outer housing Check the insulation between terminals and housing.
Overload for partially blocked pump Dismantle and check
Non-axis joint Align correctly
Ambient temperature higher than
40 °C Conditioning the environment
Abnormal heating of the external
surface of the motor Voltage below/above nominal value Check the upstream power supply
Lack of a phase Check power supply and fuses
Insufficient ventilation Check filters and ducts, resize