During rheostat braking of D.C. series motors?

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asked Mar 20, 2018 by anonymous

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asked Mar 20, 2018 by anonymous

In case of conductively compensated D.C. series motors, the compensating winding is provided?

Last answer: In case of conductively compensated D.C. series motors, the compensating winding is provided in series with armature winding.

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asked Mar 20, 2018 by anonymous

In case of D.C. shunt motors the speed is dependent on back e.m.f. only because?

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In D.C. shunt motors as load is reduced?

Last answer: In D.C. shunt motors as load is reduced the speed will remain almost constant.

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asked Mar 20, 2018 by anonymous

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Regenerative method of braking is based on that?

Last answer: Regenerative method of braking is based on that back e.m.f. is equal to the applied voltage.

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asked Mar 20, 2018 by anonymous

In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to?

Last answer: In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to 25% of the previous value.

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asked Mar 20, 2018 by anonymous

The speed of a D.C. series motor is?

Last answer: The speed of a D.C. series motor is inversely proportional to the armature current.

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asked Mar 20, 2018 by anonymous

The direction of rotation of a D.C. series motor can be changed by?

Last answer: The direction of rotation of a D.C. series motor can be changed by interchanging field terminals.

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75 views 1 answer

asked Mar 20, 2018 by anonymous

When a D.C. series motor is connected to A.C. supply, the power factor will be low because of?

Last answer: When a D.C. series motor is connected to A.C. supply, the power factor will be low because of high inductance of field and armature circuits.

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asked Mar 21, 2018 by anonymous

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A.C. series motor as compared to D.C. series motor has?

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asked Mar 20, 2018 by anonymous

If a D.C. series motor is operated on A.C. supply, it will?

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asked Mar 25, 2018 by anonymous

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Last answer: A rheostat differs from potentiometer in the respect that it has higher wattage rating.

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asked Aug 6, 2017 by anonymous

what is Rheostat ?

Last answer: Rheostat is varible resistance device which gives large range variation in resistance generally used for operating electrical motors

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Which of the following motors can run on both AC and DC?

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asked Sep 3, 2019 by anonymous

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asked May 8, 2018 by anonymous

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asked Mar 15, 2018 by anonymous

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asked Mar 20, 2018 by anonymous

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Brake test on DC series motor

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asked Apr 29, 2018 by anonymous

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asked Mar 15, 2018 by anonymous

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asked Mar 15, 2018 by anonymous

Why a dc series motor has a high starting torque?

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Explain in brief how anti-lock braking system works

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asked Mar 22, 2018 by anonymous

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Write two applications of D.C. series motor.

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asked May 25, 2018 by anonymous

The widely used series-parallel system of speed control of d.c. series motors in traction work gives a speed

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asked May 22, 2020 by anonymous

Explain the necessity of starter for D.C. motor. State various types of D.C. motor starter.

Last answer: Necessity of Starter for D.C. Motor: Armature current is given by equation Ia = (V−Eb)/Ra i) If the motor is at standstill or rest, back emf Eb is zero (as Eb= ZNP/(60A), at start speed N ... . Types of D.C. motor starters: i) Two point starter ii)Three point starter iii) Four point starter

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asked Mar 26, 2018 by anonymous

The Eb/V ratio of a d.c. motor is an indication of its?

Last answer: The Eb/V ratio of a d.c. motor is an indication of its efficiency.

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asked Mar 26, 2018 by anonymous

The normal value of the armature resistance of a d.c. motor is?

Last answer: asked Mar 26, 2018 by anonymous The normal value of the armature resistance of a d.c. motor is?

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asked Mar 26, 2018 by anonymous

The counter e.m.f. of a d.c. motor?

Last answer: The counter e.m.f. of a d.c. motor helps in energy conversion.

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asked Mar 26, 2018 by anonymous

In a d.c. motor, unidirectional torque is produced with the help of?

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asked Mar 20, 2018 by anonymous

D.C. motor is to a drive a load which is almost nil for certain part of the load cycle...

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asked Mar 20, 2018 by anonymous

D.C. motor is to drive a load which has certain minimum value for most of the time and some peak value...

D.C. motor is to drive a load which has certain minimum value for most of the time and some peak value for short duration. We will select the?

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206 views 1 answer

asked Mar 20, 2018 by anonymous

When the armature of a D.C. motor rotates, e.m.f. induced is

Last answer: When the armature of a D.C. motor rotates, e.m.f. induced is back e.m.f.

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99 views 1 answer

asked Mar 20, 2018 by anonymous

If the speed of a D.C. shunt motor is increased, the back e.m.f. of the motor will?

Last answer: If the speed of a D.C. shunt motor is increased, the back e.m.f. of the motor will increase.

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111 views 1 answer

asked Mar 26, 2018 by anonymous

A d.c. motor can be looked upon as d.c. generator with the power flow?

Last answer: A d.c. motor can be looked upon as d.c. generator with the power flow reversed.

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asked Mar 20, 2018 by anonymous

Which D.C. motor has got maximum self relieving property ?

Last answer: Series motor has got maximum self relieving property.

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129 views 1 answer

asked Mar 20, 2018 by anonymous

If a D.C. shunt motor is working at full load and if shunt field circuit suddenly opens?

Last answer: If a D.C. shunt motor is working at full load and if shunt field circuit suddenly opens this will make armature to take heavy current, possibly burning it.

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103 views 1 answer

asked Mar 20, 2018 by anonymous

Torque developed by a D.C. motor depends upon?

Last answer: Torque developed by a D.C. motor depends upon magnetic field, active length of the conductor, current flow through the conductors, number of conductors, radius of armature.

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253 views 1 answer

anonymous · Answer 1 · 2018-03-20T21:27:48+0000

answered Mar 20, 2018 by anonymous

During rheostat braking of D.C. series motors motor is run as a generator.

commented Mar 20, 2018 by anonymous

Correct it If answer is wrong?

During rheostat braking of D.C. series motors?

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