Nederman 14550128, Инструкция по эксплуатации

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NCF EN
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Table 7-1: Malfunctions and causes
Problem Cause Solution
Fan does not start No electrical connection Check that the motor and/or command inverter is connected to the
electrical power supply line and is correctly powered
Motor malfunction Check internal connections and motor components and replace if
necessary
No connection between
command inverter and motor
Check for correct connection between inverter and motor
Command inverter malfunction Check internal inverter circuits and components and replace if
necessary
Power absorption much lower
than design value
Rotation speed too low Increase rotation speed
Openings or ducting partially
blocked
Eliminate obstruction
Check the position of regulation organs
Impeller partially blocked Eliminate obstruction
Resistance pressure of system
higher than design value
Check the resistance pressure value of the system
Fluid density lower than
intended value
Check the fluid density value
Too high power absorption Rotation speed too high Reduce rotation speed
Resistance pressure of system
lower than design value
Check the resistance pressure value of the system
Incorrect impeller rotation
direction
Check impeller rotation direction and orientation
Pre-rotation of air in opposite
direction to fan rotation
Check minimum installation distances (paragraph 5.1.1) or correct
orientation of intake with pre-distributors
Fluid density higher than
intended value
Check the fluid density value
Power supply to motor with
voltage lower than shown on
identification plate
Check for correct voltage of power supply to motor
Defects in motor windings Check for correct motor operation
Insufficient pressure Rotation speed too low Increase rotation speed
Fluid density lower than
intended value
Check the fluid density value
Air flow greater than intended
value
Check the resistance pressure value of the system
Pulsating operation Instability of air flow Check operating field envisaged by operating curve
Fluctuations in flow due to other
fans operating in parallel
Check for correct installation on system
Intake air turbulence created by
system near intake opening
Check minimum installation distances.