Electrical Machines Slip rings of an induction motors are made of phosphor bronze. carbon. stainless steel. aluminium. phosphor bronze. carbon. stainless steel. aluminium. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Damper winding is used to increase the load current. both 1 and 2. decrease the load current. suppress the hunting. increase the load current. both 1 and 2. decrease the load current. suppress the hunting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : Interpoles in dc machines 1. reducearmature reaction effects in the interpolar region 2. have the same dimension as main polls 3. have their windings connected in series with the armature 4. have same number of turns as the armature 5. have the polarity same as that of the main pole ahead in a motor From these, the correct statements are 1, 2 and 3 1, 3 and 5 1 and 3 1, 2, 3 and 5 1, 2 and 3 1, 3 and 5 1 and 3 1, 2, 3 and 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a induction motor helps to reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. reduce the chance of crawling. reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. reduce the chance of crawling. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 2, 3 1, 3 2, 4 1, 4 2, 3 1, 3 2, 4 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of 3 - Φ IM, plugging means pulling the motor directly on line without a rotor. locking of rotor due to harmonics. starting the motor on load which is more than the rated load. interchanging two supply phases for quick stopping. pulling the motor directly on line without a rotor. locking of rotor due to harmonics. starting the motor on load which is more than the rated load. interchanging two supply phases for quick stopping. ANSWER DOWNLOAD EXAMIANS APP
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