Answer / rahul

of course it will not run..coz an AC motor(sync or ind)
needs rotating magnetic field which is possible to get only
if dc supply is rotating. Sync motor has arm on stator. So
no rotating field. And induction m/c run on Electromagnetic
induction principle which is not possible with dc coz ckt
saturates in dc(similar to transformer). So there can be
heavy heating followed by damage;

Answer / kapil bahadure

When AC motor motor connect on dc suplly then magnetic flux
of stater widing not cut with rotor conductor by air gap.&
not produced rotating magnetic field.then not rotate ac
motor in this condition.
Dc suplly produced to only constant magnetic field.rotating
magnetic field requried to ac motor.so not run ac motor on
dc suplly.

Answer / mahavir jagdev

Passing DC current through the stator windings of an AC motor (I presume it to be a 3-phase one and all the three phases will have DC current passing) is like passing current through copper wires with very low resistance. Depending on the DC voltage applied and the stator resistor and it's insulation strength, either the DC source will get short circuited and if the fuse is of a larger rating then the stator winding will burn out. DC current will not produce any rotating magnetic field. Some what like what we call single phasing in 3 phase motors, when the stators burn out if one phase goes off and the rotor gets locked to the lack of the rotating magnetic field.

Answer / onkar wadkar

when we given dc supply to single phase induction motor,the
single phase motor has two windings 1)stator wdg2)rotor wdg
when we have gave dc supply then in case of single phase
induction ind motor the stator side ckt acts as a purely
restive then max vtg get get dropped across the wdg and
their is no flux linkages according to the faradays law of
electromagnetic induction,and hence no emf gets induced and
consequently the motor will not start...and it results into
damage the winding of the motor...

Answer / joy mohadani

if we apply dc in ac motor is not rotating after few sec(due to inertia of the motor).but after few sec it will stop.we know that in d.c (steady) time period(t) is tense to infinity.so frequency is zero.torque is also depend upon the frequency of the motor.torque is also zero.speed falls to zero.X=2*3.14*f=0.so in motor no reactance part.path is short ckted.after a few sec motor will over heated and damaged

Answer / vikas

simply it will not run because there is no commutator in the ac machines (other than universal motor witch is commutator ac motor). so there is no choice of producing the alternating or rotating flux in the rotor or stator. constant flux will only produce which leads no rotation no back emf so according to lenz law winding may damage (over heat and burn) by drawing excess current from the supply terminals.

Answer / periyasamy.n

The a supply there is no resistance to limit the field current
, in ac only impedance will be presented it doesn't reduce the current value so the windings are damaged. Also ac will not produce the flux , so the motor does not run

Answer / nitin, s.u.k.

When we apply a d.c. source to a a.c. motors then a steady
magnetic field is developed in stator which does not
produce a rotating magnetic flux to rotate the rotor.

Answer / ajit singh

motor will not run because there is no carbon brush in ac
ac motor to change dc into ac

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