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 79
FAULT CAUSE REMEDIES
Thermal protection triggered Check the configuration of the power supply line. Check
that the pump is not blocked, check the pressure switch
calibration and the pre-charge of the autoclave tank
Switchgear failure/incorrect connec-
tions Check
Change the direction of rotation Reverse two feeding phases
The pump does not deliver water or
has a very low flow rate or delivery
head Suction depth too high. Pump cavita-
tion Review calculations based on NPSHr value from pump
Piping and suction valves of unsuitable
diameter. Pump cavitation Review calculations based on NPSHr value from pump
Air entering the suction line Check that there are no leaks in the suction line
Partially/totally closed shut-off valves Open the suction and discharge valves
Worn pump Check and repair
Pump impeller blocked Check and repair
Clogged filters Check and repair
The motor does not reach the rated
speed See next item
The motor does not reach the rated
speed Voltage too low at the ends of the
motor Check supply voltage, connections and cable cross-sec-
tions on the supply line
Uncertain contacts in the power con-
tactor 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 Check the electrical 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
Abnormal heating of the external
surface of the motor Ambient temperature higher than
40 °C Conditioning the environment
Voltage below/above nominal value Check the upstream power supply
Lack of a phase Check power supply and fuses
Unbalanced voltages on the three
phases Check the power supply
Sudden loss of speed
Instantaneous overload/foreign body
in the pump Disassemble the pump
Single-phase operation Check power supply and fuses
Voltage drop Check the power supply
Magnetic noise,
sudden whistle
Short-circuits in the motor winding Have it repaired at the factory
Slip between stator and rotor Have it repaired at the factory
Loose bolts Check and tighten
Fan cover screws loosen Check and tighten
Swipe between fan and motor cover Ensure correct distance and reassemble
Mechanical noise
Foreign bodies in the motor or pump Dismantle and remove