O&M Manual
5
Common Faults and Answers
1. What to do if fan running current is higher than specified
a) Check electrical
--Make sure supply voltage are as accordance to what is specified in the
name plate
--Make sure impeller is running in the correct rotation
--Make sure all electrical phases have constant supply for 3 phase motor
--Make sure all electrical terminals are tightened
--Make sure capacitor is correct and functioning for single phase motor
--Make sure resistance of motor winding is constant [measure (U1,U2),
(V1,V2), (W1,W2)] for 3 phase motor
--Make sure all connection are as per our electrical diagram given
c) Check for fan vibration
--Check that fan is running smoothly and not shaking vigorously
--Check that centrifugal impeller is not rubbing against the casing or inlet cone
d) Make sure inlet or outlet air passage is not blocked
2) What to do if fan cannot run
a) Check that there is incoming electrical supply to the motor
If no supply voltage across the motor
--Check the MCB, overload, thermistor is not open circuit
--Electrical panel circuit is functioning properly
b) Check that termination is correct at the motor
c) Check that capacitor is correct and is in working condition for single
phase motor
d) Check that fan impeller is smooth turning
e) Check that motor windings is OK as mentioned above
