Electrical Machines Ward Leonard control provides speed control below rated speed. above rated speed. in both direction. in one direction only. below rated speed. above rated speed. in both direction. in one direction only. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt motor has external resistance Ra and Rf in the armature and field circuits respectively. Armature current at starting can be reduced by keeping Rf maximum and Ra minimum Ra minimum and Rf minimum Ra maximum and Rf minimum Ra maximum and Rf maximum Rf maximum and Ra minimum Ra minimum and Rf minimum Ra maximum and Rf minimum Ra maximum and Rf maximum ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the mechanical power developed by a DC series motor is maximum? None of above. Back emf is equal to applied voltage. Back emf is equal to half the applied voltage. Back emf is equal to zero. None of above. Back emf is equal to applied voltage. Back emf is equal to half the applied voltage. Back emf is equal to zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of DC motor Both back emf as well as line current increase. Back emf falls and line current increase. Both back emf as well as line current fall. Back emf increase but line current falls. Both back emf as well as line current increase. Back emf falls and line current increase. Both back emf as well as line current fall. Back emf increase but line current falls. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC motors are stopped by opening line switches and not by forcing the handle of the motor starter back to OFF position. This is due to occurance of None of these. Heavy sparking at the first stud of starting resistance steps. Both of above. Heavy sparking at brushes. None of these. Heavy sparking at the first stud of starting resistance steps. Both of above. Heavy sparking at brushes. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If terminal voltage of one 1000 rpm shunt motor is reduced to half the speed of the motor will be 2000 rpm 250 rpm 500 rpm 1000 rpm 2000 rpm 250 rpm 500 rpm 1000 rpm ANSWER DOWNLOAD EXAMIANS APP