1 Answer

Answer :

Series motor should not be started on no-load.

Related questions

Description : The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a firing delay angle, α and flux, Φ (A) directly proportional to α and Φ (B) ... proportional to α and inversely proportional to Φ (D) directly proportional to Φ and inversely proportional to α

Last Answer : The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a firing delay angle, α and flux, Φ directly proportional to α and inversely proportional to Φ

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Last Answer : In a battery, the difference between the no-load voltage and the measured voltage output is called Internal resistance

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Last Answer : A no-load test is performed on a transformer to determine magnetizing current and loss.

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Last Answer : Because if the load is increasing then the torque must also be increase. If not then the speed of motor will decrease.

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Description : 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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Last Answer : In a d.c. motor, the mechanical output power actually comes from electrical input power.

Description : 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.

Description : The mechanical power developed by the armature of a d.c. motor is equal to?

Last Answer : The mechanical power developed by the armature of a d.c. motor is equal to armature current multiplied by back e.m.f.

Description : 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.

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

Last Answer : The normal value of the armature resistance of a d.c. motor is 0.5.

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

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

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Description : In DC motor iron losses are occurred in?

Last Answer : In DC motor iron losses are occurred in the armature.

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

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

Last Answer : Shunt motors,  Series motors, Compound motors

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

Last Answer : If a D.C. shunt motor is working at no load and if shunt field circuit suddenly opens this will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses.

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Description : A three-phase synchronous motor connected to ac mains is running at full load and unity power factor. lf its shaft load is reduced by half and field current is held constant then its new power factor will be

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Last Answer : The speed/load characteristics of a universal motor is same as that of D.C. series motor.

Last Answer : A synchronous motor running with normal excitation adjusts to load increases essentially by increase in armature current.

Description : The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as?

Last Answer : The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as pull-in torque.

Last Answer : The coupling angle or load angle of synchronous motor is defined as the angle between the rotor and the stator poles of opposite polarity.

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Last Answer : If the load of the normally excited synchronous motor is increased the power factor will become lagging.

Description : The synchronous motor which works on leading power factor and does not drive any mechanical load is called?

Last Answer : The synchronous motor which works on leading power factor and does not drive any mechanical load is called synchronous condenser.

Description : In a synchronous motor which losses varies with load?

Last Answer : In a synchronous motor, copper losses varies with load.

Description : The synchronous motor will develop maximum power when the load angle is?

Last Answer : The synchronous motor will develop maximum power when the load angle is 900.

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Last Answer : No, in the synchronous motor the winding losses do not vary with load.

Description : As there is no back e.m.f. at the instant of starting a D.C. motor, in order to prevent a heavy current from flowing though the armature circuit?

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