The following details are known about a 150 hp motor, 240 V, 500 rpm, dc shunt...

The following details are known about a 150 hp motor, 240 V, 500 rpm, dc shunt motor. Nominal full load current: 500 A Insulation class: H Weight: 3400 kg

Find

1.The total losses and efficiency at full load.

2.Calculate the approximate shunt filed exciting current if the shunt field causes 20% of the total losses.

3.Calculate the value of the armature resistance knowing that 50% of the total losses at full load are due to armature resistance.

4.With your calculated armature resistance, determine the counter-emf.

5.Determine the torque of the motor at full load.

6.The supply voltage is decreased to 200 V, approximate the speed at this supplied voltage.

Solutions

Expert Solution

Manojponduru answered 11 months ago

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