Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by s2. sf. sf / 2. f / s. s2. sf. sf / 2. f / s. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical on it because otherwise it will Open fuse or circuit breaker. Produce sparking at brushes. Draw too much current. Develop excessive speed and damage itself. Open fuse or circuit breaker. Produce sparking at brushes. Draw too much current. Develop excessive speed and damage itself. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The main purpose of providing tertiary winding in a three phase transformer is to interconnect three voltage systems. to suppress harmonic and unbalance in voltage. None of these to carry extra load. to interconnect three voltage systems. to suppress harmonic and unbalance in voltage. None of these to carry extra load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To control the speed of an induction motor, the supply frequency is reduced by 10%. For the same magnetizing current to remain constant, the supply voltage must be increased by 10% increased by 20% reduced by 10% reduced by 20% increased by 10% increased by 20% reduced by 10% reduced by 20% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase slip-ring induction motor, brushes are connected to 3 - Φ AC supply. DC supply. external star-connected resistors. equalizing coils. 3 - Φ AC supply. DC supply. external star-connected resistors. equalizing coils. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor is used in grinders? Split phase IM. Capacitor start capacitor run IM. Capacitor start IM. Synchronous motor. Split phase IM. Capacitor start capacitor run IM. Capacitor start IM. Synchronous motor. ANSWER DOWNLOAD EXAMIANS APP
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