Electrical Machines If starter is not used with large DC motor for starting, it will damage the armature and commutator. all of above. draw a starting current many times its rated full load current. provide execessive voltage drop in line. damage the armature and commutator. all of above. draw a starting current many times its rated full load current. provide execessive voltage drop in line. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a short circuit test on a transformer is performed at 25 V, 50 Hz, the drawn current is I1. If the test is performed by 25 V and 25 Hz and power drawn current is I2, then I1 = I2 None of these I1 > I2 I1 < I2 I1 = I2 None of these I1 > I2 I1 < I2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ward-Leonard system for controlling the speed of a DC motor is used where The speed in both the direction is required. Very fine speed control over the whole range from zero to normal speed is required. The accuracy in speed control is required. All of above. The speed in both the direction is required. Very fine speed control over the whole range from zero to normal speed is required. The accuracy in speed control is required. All of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The stator frame in an induction motor is used to protect the whole machine. ventilate the armature. provide return path for the flux. hold armature stamping in position. protect the whole machine. ventilate the armature. provide return path for the flux. hold armature stamping in position. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a standard frequency the machine operates at a particular speed known as any of the above. slip speed. synchronous speed. normal speed. any of the above. slip speed. synchronous speed. normal speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the mechanical power developed by a DC series motor is maximum? Back emf is equal to applied voltage. None of above. Back emf is equal to half the applied voltage. Back emf is equal to zero. Back emf is equal to applied voltage. None of above. Back emf is equal to half the applied voltage. Back emf is equal to zero. ANSWER DOWNLOAD EXAMIANS APP