WNF/U/2016
16/34
tel. (22) 751 95 50
www.venture.pl
fax. (22) 751 22 59
Appendix - C (EXAMPLES OF DEVICE FAULTY WORKING)
SYMPTOMS
POSSIBLE REASON
Excessive vibration or
noise
Used or damaged impeller
Fan levelled in wrong way
Dirt accumulated on impeller caused loss of balance;
Impeller loss of balance
Parts rubbing;
Damage or wear of bearings;
Damage of measurement system, that is responsible for signalization of excessive vibration.
Deformed motor shaft;
Loose of impeller fix screw, impeller is loose on motor shaft;
Loss of balance of motor impeller or damage of motor (wear/damage of bearing)
Motor overload
•Rubbing between fan impeller and housing;
•Damage or wear of bearings;
•Damage of motor windings (overheat, insulation degradation, insulation breakdown etc.);
•Damage of switch or security system;
•Failure of one of supply phases;
•Exceeding of maximum motor speed;
•Too low flow
Failed fan start-up
•Rubbing between fan impeller and housing or foreign body (e.g. tool left after installation);
•Failure of one of supply phases;
•Failure of start-up system, e.g. Y/D
•Reset of security devices has not been made, wrong security device
•Motor connected in wrong way or damaged
Too low supply voltage
Protective devices
activation during fan
work and overheating
•Excessive start-up time
•Motor overload
Motor launching done too often (thermal protection – if applied or overheating)
Improper set of protection system e.g. in system with PTC or thermocontact sensors (if applied)
•Improper cross-section of power supply wires
•Lack of sufficient motor cooling eg. dirt placed on motor cooling impeller (thermal protection – if applied or
overheating)
Too low flow
Damage of device
Too low power supply frequency
Obstacles in ventilation installation
Damaged bearings
INTRODUCTION
