Electrical Machines Iron losses in a DC machine are independent of variation in speed and voltage. load. speed. voltage. speed and voltage. load. speed. voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a loaded DC motor, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will improve and the speed falls. improve and the speed rises. deteriorate and the speed rises. deteriorate and the speed falls. improve and the speed falls. improve and the speed rises. deteriorate and the speed rises. deteriorate and the speed falls. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which 1 - Φ motor does operate at high power factor? Capacitor start. Shaded pole. Capacitor run. Split phase. Capacitor start. Shaded pole. Capacitor run. Split phase. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The application that need frequent starting and stopping is lifts and hoists. jaw crushers. paper mills. blowers. lifts and hoists. jaw crushers. paper mills. blowers. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 3, 5 1, 4, 6 1, 2, 5 1, 2, 6 1, 3, 5 1, 4, 6 1, 2, 5 1, 2, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A separately-excited DC generator, running at rated speed, has 6 volts across its armature terminals with no field current. When field winding is excited with one ampere, the voltage builds up to 250 V at no load. In case field current is reduced to zero, with the speed remaining unaltered, the armature terminal voltage would be zero more than 6 V less than 6 V 6 V zero more than 6 V less than 6 V 6 V ANSWER DOWNLOAD EXAMIANS APP