3P Induction Motors

The voltage applied to the stator of a three phase, 4 pole induction motor has a frequency of 50 Hz. The frequency of the emf induced in the rotor is 1.5 Hz. Determine the speed at which motor is running.

In a winding of a \(3\Phi\), 6 pole induction motor, the space angle between two consecutive phases is

A \(3\Phi\), 6 pole, 50 Hz induction motor develops 3.73 kW at 960 rpm. What will be the stator input if the stator loss is 280 watts?

If starting voltage of a SCIM is reduced to 50% of its rated vlue, torque developed is reduced by _ percent of its full load value.

A three-phase 4-pole 50 Hz induction motor has a rotor resistance of 0.020 ohm per phase and standstill reactance of 0.5 ohm per phase. Calculate the speed at which the maximum torque is developed.

A 50 Hp, 440 V, 3-phase, 60 Hz,6-pole squirrel cage induction motor is operating at full load and 0.8 p.f. The full load efficiency is 85% and the percentage slip is 5 %. Determine the full load torque.

The voltage applied to the stator of a three-phase, 4-pole induction motor has a frequency of 50 Hz. The frequency of the emf induced in the rotor is 1.5 Hz. Determine the speed at which motor is running.

The rotor of a 220 v, 60 Hz, 4-pole induction motor has a power input of 80 kW. It is observed that the rotor emf makes 90 cycles per minute, Calculate the rotor copper loss.

A six-pole three-phase 440-v, 60 HZ induction motor develops 10-HP at 1,150 rpm, the power factor being 80% lagging. Stator and core losses amount to 400 w and 350 w, respectively. Frictional losses amount to 0.5-hp. Calculate motor line current.

The rotor resistance of an 8-pole, 50 HZ, wound rotor induction motor is 0.5 Ω per phase The speed of the motor is 720 rpm at full load Determine the external resistance to be connected with the rotor circuit to reduce the speed to 680 rpm for full-load torque. 2 Ω

For an ac motor, the frequency is 60 Hz and the speed is 300 rpm. What is the number of poles?

A 7.5 HP, 500 v three-phase induction motor is developing its full-load output at 960 rpm. The starting torque is equal to the full-load torque. What will be the starting torque if the supply voltage fall to 400 volts?

A 50 HP, 440 v, 3-phase, 60 Hz, 6-pole squirrel cage induction motor is operating at full-load and 0.8 power factor. The full-load efficiency is 85% and the percentage slip is 5%. Determine the full-load torque.

A three-phase, 440 v, 50 Hz, 6-pole induction motor running at 950 rpm takes 50 kW at a certain load. The friction and windage loss is 1.5 kW and stator losses = 1.2 kW. Determine the output from the rotor.

If supply voltage is changed by 5% for a 3ɸ induction motor, its torque will have a change of

A six-pole, three-phase squirrel-cage induction motor is connected to a 60-cps supply. At full load, the rotor’s induced emf makes 72 complete cycles in 1 minute. Find the rotor speed.

A three- phase induction motor is taking 40 kW, the slip being 4 , stator losses amount to 800 watts, calculate the total power developed.

At a slip of 4% the maximum possible speed of 3Ø, 60HZ squirrel cage induction motor is

A three-phase induction motor having an input power of 30KW running at a slip of 4%. The stator loss is 1KW and friction and windage loss is 1.5KW. Determine the motor efficiency.

A 220 volt, 10 HP, 60 HZ, three-phase induction motor having four poles is operating at full-load slip of 3%. What is the frequency of the rotor current at full-load?