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If the centrifugal switch does not open at 70 to 80 percent of synchronous speed of motor, it would result in?

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If the centrifugal switch does not open at 70 to 80 percent of synchronous speed of motor, it would result in damage to the starting winding.

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Centrifugal switch disconnects the auxiliary winding of the motor at about what percent of synchronous speed?
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Answer :

Centrifugal switch disconnects the auxiliary winding of the motor at about 70 to 80 percent of synchronous speed.

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In case of a reluctance motor, when the load is increased so that it cannot maintain synchronous speed the motor will run as induction motor.

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If we change the excitation of synchronous machine will it affect on motor speed?

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Why the speed of synchronous motor is constant?

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Synchronous motor always runs at which speed?

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The synchronous speed of an 8 pole induction motor supplied power from a 50 Hz source will be ?

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A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The net Voltage across armature resistance at the time of plugging will be

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Answer :

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In synchronous motor, does the winding losses vary with load?

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Answer :

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

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In variable speed motor?
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Answer :

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Damper winding in a synchronous motor

Answer :

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The speed of a D.C. motor can be controlled by varying  1. Its flux per pole 2. Resistance of armature circuit 3. Applied voltage 4. All of the above

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Answer :

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Answer :

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speed control methods of three phase induction motor?

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The effect of increasing load on a synchronous motor running with normal excitation is (A) Increase both its Ia and power factor. (B) Decrease Ia, but increase power factor. (C) Increase Ia, but decrease power factor (D) Decrease both Ia and power factor.

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Why synchronous motor Cannot start itself?

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What is the principle of synchronous motor?

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What is the use of synchronous motor?

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Can we make power factor of synchronous motor leading by adjusting its excitation?
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Answer :

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what is the difference between synchronous and asynchronous motor?

Answer :

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Why does the speed of a DC shunt motor decrease as the load increases?

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If the synchronous motor, properly synchronised to the supply is running on no load and is having negligible loss then?
Description :

Answer :

If the synchronous motor, properly synchronised to the supply is running on no load and is having negligible loss then the stator current will be zero.

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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) inversely proportional to α and Φ (C) directly proportional to α and inversely proportional to Φ (D) directly proportional to Φ and inversely proportional to α

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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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Answer :

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The maximum torque which a synchronous motor will develop at rest for any angular position of the rotor, at rated stator supply voltage and frequency, is known as?

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asked Mar 20, 2018 by anonymous
If the load of the normally excited synchronous motor is increased the power factor will?
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If the load of the normally excited synchronous motor is increased the power factor will?

Answer :

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

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asked Mar 18, 2018 by anonymous
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If the field of synchronous motor is under excited, power factor will be?

Answer :

If the field of synchronous motor is under excited, power factor will be lagging.

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A synchronous motor running with normal excitation adjusts to load increases essentially by increase in?
Description :

Answer :

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

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asked Mar 20, 2018 by anonymous
Hunting in synchronous motor cannot be due to?
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Hunting in synchronous motor cannot be due to?

Answer :

Hunting in synchronous motor cannot be due to windage friction.

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asked Mar 18, 2018 by anonymous
The damping winding in synchronous motor is generally used to?
Description :

The damping winding in synchronous motor is generally used to?

Answer :

The damping winding in synchronous motor is generally used to provide starting torque and prevent hunting.

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asked Mar 18, 2018 by anonymous
A synchronous motor has better power factor as compared to that of an equivalent induction motor...
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A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because?

Answer :

A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because stator supply is not required to produce magnetic field.

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