A 220 V shunt motor develops a torque of 54 N-m at armature current of 10 A. The torque produced when the armature current is 20 A, is?

2 Answers

Answer :

A 220 V shunt motor develops a torque of 54 N-m at armature current of 10 A. The torque produced when the armature current is 20 A, is 108 N-m.

Answer :

Armature torque, Ta=PØZIa/2πA

So Ta1/Ta2=Ia1/Ia2

Ta2=Ta1*Ia2/Ia1

       =54*20/10

        =108

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