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?

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asked Mar 20, 2018 by anonymous

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

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

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

If we change the excitation of synchronous machine will it affect on motor speed?
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Synchronous motor always runs at which speed?

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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Damper winding in a synchronous motor

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Last Answer : Damper winding in a synchronous motor Serves to start the motor.

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The maximum reluctance power of a salient-pole synchronous motor having direct-axis reactance, 1.0 pu and

The maximum reluctance power of a salient-pole synchronous motor having direct-axis reactance, 1.0 pu and quadrature-axis reactance, 0.5 pu, and input voltage, 1.0 pu is (A) 0.25 pu (B) 0.5 pu (C) 1.0 pu (D) 1.5 pu
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The effect of increasing load on a synchronous motor running with normal excitation is

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Last Answer : The effect of increasing load on a synchronous motor running with normal excitation is Increase Ia, but decrease power factor

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A three-phase synchronous motor connected to ac mains is running at full load and unity power factor.

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Why synchronous motor Cannot start itself?

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

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

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what is the difference between synchronous and asynchronous motor?
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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.

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Last Answer : 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 474 V

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If the field winding of an unloaded salient pole synchronous motor is open circuited, the motor will?

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The speed of a D.C. shunt motor can be increased by?

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For the same H.P. rating and full load speed, following motor has poor starting torque?

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speed control methods of three phase induction motor?

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List different starting methods of three phase synchronous motor. Explain any one of them.

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asked May 7, 2020 by anonymous

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asked May 7, 2020 by anonymous

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List different torques in synchronous motor.
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asked May 7, 2020 by anonymous

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Slip-rings in a synchronous motor carry?

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The efficiency of a properly designed synchronous motor will usually fall in range?

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asked Mar 20, 2018 by anonymous

A synchronous motor has better power factor as compared to that of an equivalent induction motor...

A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because?
Last 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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asked Mar 20, 2018 by anonymous