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Answer :

Single phase induction motor usually operates on 0.6 power factor lagging.

Related questions

Description : A capacitor-start single phase induction motor is switched on to supply with its capacitor replaced by an inductor of equivalent reactance value. It will?

Last Answer : A capacitor-start single phase induction motor is switched on to supply with its capacitor replaced by an inductor of equivalent reactance value. It will not start at all.

Description : Explain the working of a single phase capacitor start induction motor. 

Last Answer : Single phase capacitor start induction motor https://youtu.be/31lvvzU5Puc

Description : What is the slip (as a percentage) when a 6 pole single phase induction motor operating on 220 V and 60 Hz is rotating at speed of 1140 rpm? A) 60% B) 5% C) 10% D) None of these

Last Answer : What is the slip (as a percentage) when a 6 pole single phase induction motor operating on 220 V and 60 Hz is rotating at speed of 1140 rpm? A) 60% B) 5% C) 10% D) None of these

Last Answer : If a single phase induction motor runs slower than normal, the most likely defect is worn bearings.

Description : How does a single phase induction motor work?

Last Answer : As we know that single phase induction is not self started because for self started we require atleast two revolving field but single phase induction motor has only one. So we provide extra ... 1phase IM classified as split phase IM, capacitor start capacitor run, capacitor start induction run.

Description : explain the working of single phase induction motor.

Last Answer : Stator has two winding namely main winding and auxiliary winding.when single phase ac supply is given to the motor,its produces alternating field.this field cut by a cage rotor.so some emf ... due to this emf,rotor flux produced.the interaction between two fluxes produce torque.so rotor rotates.

Description : Single Phase Induction Motor

Last Answer : Single Phase Induction Motor Single phase induction motor is mostly used in home, office, shop and many single phase appliances like pumps,  ... torque and silent operation. It is uses where silent operation is required.

Description : The running winding of a single phase motor on testing with meggar is found to be ground. Most probable location of the ground will be?

Last Answer : The running winding of a single phase motor on testing with meggar is found to be ground. Most probable location of the ground will be at the slot edge where coil enters or comes out of the slot.

Last Answer : In a single phase motor the centrifugal switch disconnects auxiliary winding of the motor.

Description : SINGLE PHASE INDUCTION MOTORS MCQ

Last Answer : 101. After the starting winding of a single phase induction motor is disconnected from supply, it continues to run only on (a) running winding (b) rotor winding (c) field winding (d) compensating winding Ans: a ... motor is usually reduced by using (a) gearing (b) belts (c) brakes (d) chains Ans: a

Last Answer : Induction type single phase energy meters measure electric energy in kWh.

Description : State any four advantages of three phase induction motor. 

Last Answer : Advantages of three phase induction motor https://youtu.be/27OIOCKN05U

Description : Split phase induction motor

Last Answer : Split phase induction motor : There are two windings used in split phase induction motor. It is a type of single-phase induction motor. There are two winding one is called main winding and ... motor have low starting torque it is used for small fans, blowers, centrifugal pumps, grinders etc.

Description : The slip of 400 V, three phase, 4 -pole induction motor when rotating at 1440 rpm is 

Last Answer : The slip of 400 V, three phase, 4 -pole induction motor when rotating at 1440 rpm is 4 percent

Description : How is a three phase cage induction motor self starting?

Last Answer : Any type of induction motor is self starting. Because the reason for torqe production require two flux displaced by some angle theta.If theta is constant with time then torqe will be constant;if ... torqe also pulsating. In induction motor this angle theta is not pulsating.so it is self starting 

Description : What is mean by plugging in three phase induction motor?

Last Answer : Plugging in three-phase induction motor means interchanging of any two phases of a stator for quick stopping.

Description : how can we reverse the direction of rotation of three phase induction motor ?

Last Answer : The direction of rotation of three phase induction motor can be reversed by plugging i.e by changing any two out of three phases of the supply to the stator of the Induction motor terminal.

Description : speed control methods of three phase induction motor?

Last Answer : Speed control of three phase induction motor

Description : State suitable single phase motor for following applications: (i) Table fan (ii) Mixers and Grinders

Last Answer : Application Suitable Single Phase Motor Table Fan 1) Capacitor split phase motor 2) Capacitor start capacitor run motor Mixers and Grinders 1) Universal motor 2) A.C. Series motor

Description : Why is a capacitor used in a single phase motor and not in three phase motor ?

Last Answer : In 1-phase induction motor capacitor work is generate the auxiliary winding current than excite the main winding to rotor starts rotate. After rotor start rotating about 75% of their speed than auxiliary ... emf to start the motor.so,in 3-phase induction motor is self start induction motor.

Description : working principle of single phase motor

Last Answer : The Stator of single phase induction motor houses two windings  1. Main (Running) winding 2. Auxiliary (Starting ) winding Rotor of single phase induction motor is ... with starting winding or a capacitor may be permanently connected in series with Auxiliary (Starting ) winding.

Last Answer : Starting winding of a single phase motor of a refrigerator is disconnected from the circuit by means of a magnetic relay.

Description : An unexcited single phase synchronous motor is ?

Last Answer : An unexcited single-phase synchronous motor is reluctance motor.

Last Answer : The power factor of a single-phase induction motor is usually lagging.

Last Answer : A single-phase induction motor is inherently non-self-starting with low torque.

Description : The number of poles in a phase induction motor at 50 Hz and running at 1500 rpm will be?

Last Answer : The number of poles in a phase induction motor at 50 Hz and running at 1500 rpm will be 4.

Last Answer : The repulsion-start induction-run motor is used because of high starting torque.

Description : The disc of a single phase Induction-type energy meter makes 60 revolutions in 6 minutes. Meter Constant is 1200 rev/kWh. Power consumption in the load is (A) 1.2 kW (B) 1 kW (C) 600 W (D) 500 W

Last Answer : The disc of a single phase Induction-type energy meter makes 60 revolutions in 6 minutes. Meter Constant is 1200 rev/kWh. Power consumption in the load is 500 W

Description : In a single-phase induction motor, the operating direction is determined by the ________ A) Rotor B) Stator C) Starting circuit D) None of these

Last Answer : In a single-phase induction motor, the operating direction is determined by the Starting circuit

Description : In a single-phase induction motor when the rotor is stationary and voltage is applied to the stator, then (A) the flux is constant (B) the flux first decreases and then increases in ... increases and decreases in the opposite direction with the same magnitude (D) current flows through the rotor

Last Answer : In a single-phase induction motor when the rotor is stationary and voltage is applied to the stator, then the flux first decreases and then increases in the same direction

Last Answer : If starting winding of a single-phase induction motor is left in the circuit, it will draw excessive current and overheat.

Last Answer : Capacitor start motor has high torque in starting

Last Answer : Direction of rotation of a split phase motor can be reversed by reversing the connection of either running winding or starting winding.

Last Answer : In a split phase motor the starting winding is connected through a centrifugal switch.

Last Answer : In a capacitor start motor, the phase displacement between starting and running winding can be nearly 90°.

Last Answer : In a split phase motor, the running winding should have low resistance and high inductance.

Last Answer : The rotor slots, in an induction motor, are usually not quite parallel to the shaft because it helps in reducing the tendency of the rotor teeth to remain under the stator teeth.

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Description : The speed of a three-phase induction motor is controlled by variable voltage variable frequency control (i.e. keeping V/f constant). As the frequency is reduced, the slip at maximum torque  (1) Decreases (2) Increases (3) Remains constant (4) None of the above

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Description : Torque developed by a three-phase, 400V, induction motor is 100 N -m. If the applied voltage is reduced to 200-V, the d'veloped torque will be

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Description : A 400 V, 50 Hz three-phase induction motor rotates at 1440 rpm on full -load. The motor is wound for

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Description : In a split-phase induction motor, the resistance/reactance ratios of windings are such that (A) current in the auxiliary winding leads the current in the main winding (B) current in the ... (C) both windings develop the same starting torque (D) both windings develop high starting current

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Description : A 3-phase, 4-pole, 50Hz induction motor runs at a speed of 1440 rpm. The rotating field produced by the rotor rotates at a speed of ________ rpm with respect to stator field. (A) 1500 (B) 0 (C) 1440 (D) 60

Last Answer : 0

Description : An 8-pole, 50Hz, three-phase induction motor is running at 705rpm and has a rotor copper loss of 5kW. Its rotor input is (A) 5.06 kW (B) 0.3 kW (C) 100 kW (D) 83.33 kW

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Description : In a 3-phase slip-ring induction motor, the slip at some speed is 0.05. The speed is reduced by inserting an external resistance in the rotor circuit and the slip is 0.15. If the rotor winding resistance per phase is 0.2 Ω, the external resistance is (A) 0.2 Ω (B) 0.3 Ω (C) 0.4 Ω (D) 0.5 Ω

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Last Answer : Circuit Diagram: Waveforms:

Description : Single phase transformer

Last Answer : Single phase Transformer Transformer

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