Vents VPQ 710, User Manual, Page: 14 / 20

14
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Prior to performing any technical maintenance and repair disconnect the fan from the electric mains and wait until its rotating parts
come to a complete stop.
While performing technical maintenance:
• Check the grounding screw terminals and electric connectors for proper tightness and tighten them up if necessary.
• Check the casing fastening screws for tightness and tighten them up if necessary.
• Check the bolt connecting the motor shaft to the hub for proper tightness and tighten it up if necessary.
• Check the fan impeller for contamination and clean it up if necessary. To clean the impeller, remove the side cover.
Technical maintenance must be carried out at least once a year.
DISCONNECT THE UNIT FROM POWER SUPPLY BEFORE
ANY MAINTENANCE OPERATIONS!
AVOID LIQUID SPILLS ON THE MOTOR! DO NOT USE AGGRESSIVE SOLVENTS AND
SHARP OBJECTS FOR CLEANING!
PRIOR TO COMMENCING ANY TECHNICAL MAINTENANCE PUT UP A PROHIBITORY
SIGN ON THE FAN STARTING PANEL:
“DO NOT SWITCH ON! MEN AT WORK!”
POSSIBLE MALFUNCTIONS AND THEIR ELIMINATION
Problem Possible reasons Elimination
The fan will not start. No power supply. Check the mains switch. Check the electrical connections
against the wiring diagram.
Jammed motor. Carefully check the fan impeller for possible seizure and
eliminate it, if necessary. If the impeller is in order, replace
the electric motor.
The switching equipment
activates upon fan start-up.
Short circuit in the fan or the electric circuit between
the fan and the switching equipment.
Eliminate the cause of a short circuit.
Excessive current consumption due to an overload in
the electric mains.
Eliminate the cause of excessive current consumption.
Improper fan starting method. Use a soft starter or frequency converter to start the motor
(see "Asynchronous Electric Motor Starting Methods"
in the "Connection to power mains" section)
.
Improper switching equipment. Re-select the switching equipment in accordance with the
current regulations and equipment specifications.
The installed switching equipment is of poor quality
or its actual performance falls short of the rated values
stated by the manufacturer.
Re-select the switching equipment by choosing a unit
which successfully passed commutation and load tests
and has a technical compliance certificate. The selection
should be limited to the top five foreign switching
equipment manufacturers.
TECHNICAL MAINTENANCE