Last Answer : The power factor of a single-phase induction motor is usually lagging.
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191 views
1 answer
asked
Mar 20, 2018
by
anonymous

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
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129 views
1 answer
asked
Apr 29, 2018
by
anonymous

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
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95 views
1 answer
asked
Apr 28, 2018
by
anonymous

Last Answer : If starting winding of a single-phase induction motor is left in the circuit, it will draw excessive current and overheat.
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235 views
1 answer
asked
Mar 20, 2018
by
anonymous

Last Answer : In a capacitor start single-phase motor, when capacitor is replaced by a resistance motor will continue to run in same direction.
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223 views
1 answer
asked
Mar 20, 2018
by
anonymous

Last Answer : In a shaded pole single-phase motor, the revolving field is produced by the use of shading coils.
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205 views
1 answer
asked
Mar 20, 2018
by
anonymous

Last Answer : The rotor developed by a single-phase motor at starting is zero.
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90 views
1 answer
asked
Mar 20, 2018
by
anonymous

Last Answer : If the capacitor of a single-phase motor is short-circuited the motor will not start.
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104 views
1 answer
asked
Mar 20, 2018
by
anonymous
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Last Answer : Single phase induction motor usually operates on 0.6 power factor lagging.
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127 views
1 answer
asked
Mar 20, 2018
by
anonymous

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.
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232 views
1 answer
asked
Mar 20, 2018
by
anonymous
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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.
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143 views
1 answer
asked
Mar 26, 2018
by
anonymous

Last Answer : The repulsion-start induction-run motor is used because of high starting torque.
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89 views
1 answer
asked
Mar 20, 2018
by
anonymous

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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150 views
1 answer
asked
Apr 28, 2018
by
anonymous

Last Answer : The starting winding of a single-phase motor is placed in stator.
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115 views
1 answer
asked
Mar 20, 2018
by
anonymous

Explain the working of a single phase capacitor start induction motor.
Last Answer : Single phase capacitor start induction motor https://youtu.be/31lvvzU5Puc
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398 views
2 answers
asked
Jul 30, 2019
by
anonymous

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
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126 views
1 answer
asked
Apr 29, 2018
by
anonymous

Last Answer : Reason is kinetic energy
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285 views
2 answers
asked
Mar 20, 2018
by
anonymous

Last Answer : If a single phase induction motor runs slower than normal, the most likely defect is worn bearings.
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170 views
1 answer
asked
Mar 20, 2018
by
anonymous

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.
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124 views
1 answer
asked
Mar 17, 2018
by
anonymous

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.
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187 views
1 answer
asked
Oct 24, 2017
by
anonymous

Last Answer : Capacitor start motor has high torque in starting
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135 views
1 answer
asked
Sep 13, 2017
by
anonymous

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.
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528 views
1 answer
asked
Aug 9, 2017
by
anonymous

Basic electrical engineering
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12 views
0 answers

Explain with neat circuit diagrams the procedures to perform no load and blocked rotor tests on three phase induction motor.
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133 views
0 answers
asked
Apr 16, 2020
by
anonymous

Explain the need and steps to conduct the reduced voltage running up test on the three phase induction motor.
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223 views
0 answers
asked
Apr 16, 2020
by
anonymous

State any four advantages of three phase induction motor.
Last Answer : Advantages of three phase induction motor https://youtu.be/27OIOCKN05U
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138 views
2 answers
asked
Jul 30, 2019
by
anonymous

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.
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230 views
1 answer
asked
Sep 20, 2018
by
anonymous

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
Last Answer : 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 Increases
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235 views
1 answer
asked
May 1, 2018
by
anonymous

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
Last Answer : 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 25 N -m
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422 views
1 answer
asked
Apr 29, 2018
by
anonymous

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
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362 views
1 answer
asked
Apr 29, 2018
by
anonymous

A 400 V, 50 Hz three-phase induction motor rotates at 1440 rpm on full -load. The motor is wound for
Last Answer : A 400 V, 50 Hz three-phase induction motor rotates at 1440 rpm on full -load. The motor is wound for 4 poles
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305 views
1 answer
asked
Apr 29, 2018
by
anonymous

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
Last Answer : In a split-phase induction motor, the resistance/reactance ratios of windings are such that current in the auxiliary winding leads the current in the main winding
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106 views
1 answer
asked
Apr 28, 2018
by
anonymous

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
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2.1k views
2 answers
asked
Apr 28, 2018
by
anonymous

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
Last Answer : An 8-pole, 50Hz, three-phase induction motor is running at 705rpm and has a rotor copper loss of 5kW. Its rotor input is 83.33 kW
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179 views
1 answer
asked
Apr 28, 2018
by
anonymous
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The torque developed by any 3-phase induction motor at 0.8 p.u. slip is (A) Full-load torque (B) unstable torque (C) starting torque (D) break down
Last Answer : The torque developed by any 3-phase induction motor at 0.8 p.u. slip is unstable torque
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3.1k views
1 answer
asked
Apr 28, 2018
by
anonymous

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
Last Answer : 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 0.3 Ω
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167 views
1 answer
asked
Apr 28, 2018
by
anonymous

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
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160 views
1 answer
asked
Mar 17, 2018
by
anonymous

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.
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155 views
1 answer
asked
Mar 3, 2018
by
anonymous

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.
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137 views
1 answer
asked
Oct 4, 2017
by
anonymous
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speed control methods of three phase induction motor?
Last Answer : Speed control of three phase induction motor
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364 views
2 answers
asked
Aug 9, 2017
by
anonymous

Explain the working principle of induction motor.
Last Answer : Working principle of induction motor: * When the motor is excited with three-phase supply, three-phase stator winding carries three-phase currents & produces a rotating magnetic field of constant magnitude and ... , which tend to move the rotor in the same direction as the rotating magnetic field.
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588 views
1 answer
asked
May 22, 2020
by
anonymous
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Explain the activities carried out during weekly maintenance of 3 ph. Induction motor.
Last Answer : Activities Carried out During Weekly Maintenance of 3 ph. Induction Motor: 1) Check belt tension. In cases where this is excessive it should immediately be reduces and in the case of sleeve ... and cooled by oil mist systems its important to check the oil mist flow paths/pressure components.
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163 views
1 answer
asked
May 7, 2020
by
anonymous

State the function of following parts in Induction motor. (i) Stator (ii) Slip rings
Last Answer : Name of part Function Stator 1) Stator frame supports the core, terminal box and protects the inner parts. 2) Stator core houses stator winding. 3) Stator winding ... ) Provides facility to connect external resistance to rotor circuit through brushes for starting and control.
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221 views
1 answer
asked
May 7, 2020
by
anonymous

List the energy conservation technique in induction motor.
Last Answer : Following are the list of energy conservation techniques in electrical motors: 1) Reduction in iron losses by using low loss silicon steel core material laminated to thinner dimension. 2) Using bigger length ... at light load. 13) By rewinding in induction motor 14) By motor survey
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1.1k views
1 answer
asked
May 3, 2020
by
anonymous

With a neat sketch give the working of shaded pole induction motor.
Last Answer : Explanation: It has squirrel cage rotor and salient pole stator. The stator poles are shaded partially by short circuited conductor band to create the phase difference between the fluxes emerging from shaded ... rotating magnetic field in the air-gap and torque is exerted on the squirrel cage rotor.
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265 views
2 answers
asked
Apr 27, 2020
by
anonymous

What will happen if the induction motor runs at synchronous speed ?
Last Answer : Since there is always slip present in rotor it cannot run at synchronous speed no current will be developed hence no torque will developed
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113 views
3 answers
asked
Aug 18, 2019
by
anonymous

Define Slip of Induction Motor.
Last Answer : Slip: It is the ratio of relative speed of rotor (difference between synchronous speed and rotor speed) to the synchronous speed of rotating magnetic field. Slip = (NS – N) / NS where , NS = synchronous speed, N = speed of rotor
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59 views
1 answer
asked
Aug 17, 2019
by
anonymous

Last Answer : Energy conservation technique in induction motor by minimizing idle and redundant running of motor: 1) Loss of energy as the no load power drawn is approximately about 12% to 16% of rated ... to unnecessary line losses. 4) Reduction in overall system energy efficiency over period of time.
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691 views
1 answer
asked
Sep 22, 2018
by
anonymous

State and explain any four factors governing selection of induction motor.
Last Answer : The factors governing the selection of Induction motor: 1) Load torque required at normal speed matches with available torque of motor. 2) Break down torque or pull out torque or maximum torque ... If selecting energy efficient motor the cost benefit analysis over the long run must be worked out.
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2.8k views
1 answer
asked
Sep 22, 2018
by
anonymous

Explain energy conservation technique “by improving power quality” for induction motor.
Last Answer : Energy conservation method in induction motor by improving power quality: Electrical energy can be conserved by improving the power quality. It can be achieved by avoiding voltage unbalance, maintaining ... losses can be minimized by using harmonic filter thus reducing the harmonics in the system.
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3.6k views
2 answers
asked
Sep 22, 2018
by
anonymous
