Answer / ashli

when a motor rotates a back emf(E) is induced in the
armature which will oppose the supply voltage(V).. E is
proportional to the speed ie at zero speed there ll be no
back emf.. the current thro' the armature is (V-E)/R; where
R is the armature winding resistance(small value). at the
instant of starting speed is zero and so the value of E.
thus the current = V/R becomes very high.. once it attain
speed E is generated and current falls down

Answer / prakash suhane

During start motor requires high torque to get rated speed.
Requirement of high starting torque leads to large back
E.M.F and t6o overcome this back EMF high current flows
during starting of motor. once motor reached its rated
speed current reduced as per load current on motor.

Answer / rambabu

During start motor requires high torque to get stating load
is zero.also this will given lower o/p voltege per RPM.but a
higher current per phase

Answer / chreamz

During starting time, the motor acts like a blocked rotor.
The flux created on the armature turn to oppose that of the
rotor. Hence the motor amperage rises far beyond the
rating. It's estimated that, during starting time of the
motor, Operating Current = 6 times Norminal Current.

Answer / gaju

what is ripple component in ac supply?

hai iam arunkumar. i have applied for an section enginner in rrb. i want lat 5 years solved question papers. if u have please sedn it to arun30682@gmail.com

0 Answers   RRB,

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12 Answers   ABB, Adani, Central Electricals, Electrical, HCL,

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