Answer / zahid noor

This question is wrong, it should be what causes ARE
RESPONSIBLE FOR burning of ELECTRICAL motor.
The answer is Motors are burnt due to over heating of
windings, insulation failure,bearing/bush wear & tear, lack
of maintenance like greasing in rotating DE & NDE side ,
under voltage, over voltage & above all due to lack of
protection relays ie if bimetallic over load relays with
proper setting as per running load & Full load current of
motor is provided, motor can not burnt & it will trip on
any abnormal condition.

Answer / jesus

-Lack of maintenance.
-If the AC power applied is higher than the parameters
already specified for that specific motor.

Answer / vikash gupta

in case of ac e=-N d(phi)/dt
when in ac motor we applied dc,since in dc, fulx is always
constant,so rate of change of flux w.r.t. time is zero.so
there is no back emf which limits the extremly high
current,that's why due to high current AC Electrical Motor
is burnt.

Answer / yuvi

Most common reasons
1. Mechanical failure (lubrication, bearings and bushes
etc,.)
2. Insulation failure

Some more reasons I could think of
1. Abuse of the motor (use of ordinary motor like a heavy
duty motor)
2. Improper starters used, frequent restarting of motors.
3. Low quality power supply or wrong type of power source
(DC, 3phase etc.,)

Answer / guest

over voltage,bearing damage, misalignment to the load

Answer / bibek

I think motor burns due to lack of maintenance.bearing problem.wrong stator. Wrong O/L relay protection..,,Single phasing..If it is a sleepring motor the another cause is open circuit ROTOR.

Answer / ramesh

over load if protection is not given

Answer / varun tripathi

1 lack of maintenance. bearings quality,focous on zero-2 motor assembly,
2 check no load amp.& compare with on load amp. it is in range as name
plate .check mech. s/m healthy
3 long servicing renderd of motors. also affect its insulation, rotors strips etc.
4 protection of relay with sute range.& power factor 0.8 = or greater
,supply voltage as need spcification

Answer / dipen dalsaniya

due to the lack of maintenance motor burnt out
over heating,insulation failure

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