DC motors are stopped by opening the line switches and not by forcing the handle of the motor starter back to OFF position. This is due to occurrence of
Heavy sparking at the first stud of the starting resistance steps
A dc shunt motor is driving a constant torque load with normal excitation. If the filed current is halved then the motor will run at
A dc shunt motor is driving a mechanical load at rated voltage with normal excitation. If the load torque is increased to double of the normal one, the speed of the motor will