# Full load current of an Induction motor is 20 Ampere. The no-load current may be expected to be:

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Full load current of an Induction motor is 20 Ampere. The no-load current may be expected to be: A) 25 Ampere to 28 Ampere B) 15 Ampere to 18 Ampere C) 11 Ampere to 14 Ampere D) 6 Ampere to 10 Ampere

Full load current of an Induction motor is 20 Ampere. The no-load current may be expected to be:  6 Ampere to 10 Ampere

## Related questions

The power factor of an induction motor under no load conditions will be close to (A) 0.2 lagging (B) 0.2 leading (C) 0.5 lagging (D) Unity

Under no load condition, if the applied voltage to an induction motor is reduced from the rated voltage to half the rated value,  (A) the speed decreases and the stator current increases (B) both the speed and the stator current decreases (C) the speed and the stator current remain practically constant (D) there is negligible change in the speed but the stator current decreases

The no~load current of a single phase induction motor is around _____% of full load current.  (1) 10 (2) 20 (3) 40 (4) 80

An induction motor having full load torque of 60 Nm when delta connected develops a starting torque of 120 Nm. For the same supply voltage if the motor is changed to star connection, the starting torque developed will be  A) 40 Nm B) 60 Nm C) 90 Nm D) 120 Nm

The type of single-phase induction motor having the highest power factor at full load is (A) shaded pole type (B) split-phase type (C) capacitor-start type (D) capacitor-run type

A 400 V, 15 kW, 4-pole, 50 Hz, Y-connected induction motor has full load slip of 4%. The output torque of the machine at full load is  (A) 1.66 Nm (B) 95.50 Nm (C) 99.47 Nm (D) 624.73 Nm

No-load test on a 3-phase induction motor was conducted at different supply voltage and a plot of input power versus voltage was drawn. This curve was extrapolated to intersect the y-axis. The intersection point yields  (A) Core loss (B) Stator copper loss (C) Stray load loss (D) Friction and windage loss

The frequency (fr) of the rotor current in an induction motor is given by the expression (s = slip, f = supply frequency)

The maximum torque of an induction motor is 200 kg-m at a slip of 12%. The torque at 6% slip would be (a) 100 kg-m (b) 160 kg-m (c) 50 kg-m (d) 40 kg-m

An 8-pole alternator runs at 750 rpm and supplies power to a 6-pole induction motor which has a full load slip of 3 percent. The full load speed of the induction motor will be: A) 1000 rpm B) 920 rpm C) 950 rpm D) 970 rpm

In a d.c. series motor, the torque developed is 20 Nm at 10A. If the load current is doubled, the new torque will be : -  a) 60 Nm b) 45 Nm c) 80 Nm d) 100 Nm

A large transformer operating at no load draws an exciting current Io of 5A, when the primary is connected to a 120 V, 60 Hz source. From a wattmeter test, it is known that iron losses are equal to 180 W. Calculate the reactive power absorbed by the core.  (A) 600 var (B) 572 var (C) 180 var (D) 360 var

The no-load current drawn by transformer is usually what per cent of the full-load current ?

The effect of increasing the length of air gap in an induction motor is to increase the (a) power factor (b) speed (c) magnetising current (d) air gap flux

The ratio of rotor output to rotor input in an induction motor is 0.96. The slip of the motor is (a) 0.04% (b) 4% (c) 6% (d) 12%

The no load speed of a d.c. shunt motor is 1140 rpm. At full load, the armature reaction weakens the main flux by 5% whereas the armature circuit voltage drops by 10%. The motor full load speed in rpm will be: (A) 1080 (B) 1203 (C) 1000 (D) 1200

In a single phase induction motor driving a fan load, the reason for having a high resistance rotor is to achieve (A) low starting torque (B) quick acceleration (C) high efficiency (D) reduced size

When the supply voltage to an induction motor is reduced by 10%, the maximum torque will decrease by about  A) 5% B) 10% C) 20% D) 40%

A d.c. shunt motor runs at no load speed of 1140 r.p.m. At full load armature reaction weakens the main flux by 5%. Whereas the armature circuit voltage drops by 10%. The full load speed of the motor is (a) 1200 r.p.m. (b) 1080 r.p.m. (c) 1040 r.p.m. (d) 1000 r.p.m.

A three phase induction motor is driving full -load torque which is independent of speed. If the line voltage drops to 90% of the rated value, % increase in motor copper losses  (a) 23% (b) -18% (c) 123% (d) None of these

A 50 Hz, 3—phase induction motor has a full load speed of 1440 rpm. The number of poles of the motor is:   (A)4 (8)6 (0)12  (D)8

The usual value of slip of a 3Φ induction motor at full load is about:  (A) 0.05 (B) 0.1 (C) 0.3 (D) 0.8

The reading of wattmeter in no load test of induction motor gives : (A) Friction and windage loss (B) Copper losses on no load in the stator (C) Core losses (D) Sum of all losses

A three phase, salient pole synchronous motor is connected to an infinite bus. It is operated at no load a normal excitation. The field excitation of the motor is first reduced to zero and then increased in reverse direction gradually. Then the armature current.  (A) Increases continuously (B) First increases and then decreases steeply (C) First decreases and then increases steeply (D) Remains constant

The actual speed of an induction motor is always • Less than synchronous speed • More than synchronous speed • Equal to synchronous speed • None of the above.

In a 2 kW, 200 V, 1000 rpm. DC series motor the torque at full load was found to be 0.3 N -m. The torque at half full load in N -m is :

A 400kW, 3 -phase, 440V, 50Hz induction motor has a speed of 950 rpm on full load. The machine has 6 poles. The value of slip for the machine will be (A) 0.06 (B) 0.10 (C) 0.04 (D) 0.05

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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Which statement out of the following is a wrong statement with regard to Induction motor? A) Auto-transformer starter is costlier to “direct on line” (DOL) starter B) DOL starter is used for motors up to 5 horse power only C) Auto transformer starter is used for motors up to 20 horse power only D) Star delta starter connects the motor first in delta at the time of starting then in star for running

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

The slip of an induction motor normally does not depend on  (A) rotor speed (B) synchronous speed (C) shaft torque (D) core-loss component

A 3-phase induction motor is driving a constant torque load at rated voltage and frequency. If both voltage and frequency are halved, following statements relate to the new condition if stator resistance, leakage reactance and core loss are ignored  1. The difference between synchronous speed and actual speed remains same 2. The airgap flux remains same 3. The ... . slip remains same Among the above, current statements are  (A) All (B) 1, 2 and 3 (C) 2, 3 and 4 (D) 1 and 4

The average power delivered to an impedance 4 − j 3 Ω by a current 5Cos(100πt + 100) Ampere is A) 44.2 W B) 50 W C) 62.5 W D) 125 W

A 220 V dc machine has an armature resistance o f 1-ohm. If the full load current is 20A, the difference in the induced voltage when the machine is running as a motor, and as a generator is

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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?

Suggest the energy conservation techniques in following cases : (i) Motor is running with 70% loaded condition. (ii) Motor is continuously loaded at 50%. (iii) Motor runs with 30% loaded condition but sometimes rises to 50% loading condition. (iv) Motor runs continuously under no-load condition.

The d.c. series motor should never be switched on at no load because?