Electrical Machines A large series motor is never started without some mechanical on it because otherwise it will Develop excessive speed and damage itself. Draw too much current. Produce sparking at brushes. Open fuse or circuit breaker. Develop excessive speed and damage itself. Draw too much current. Produce sparking at brushes. Open fuse or circuit breaker. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 400 / 200 V, Y - Y connected wound rotor induction motor has 0.06 Ω rotor resistance and 0.3 Ω standstill reactance per phase. To make the starting torque equal to maximum torque of the motor the additional resistance required 0.78 Ω. 0.45 Ω. 0.66 Ω. 0.24 Ω. 0.78 Ω. 0.45 Ω. 0.66 Ω. 0.24 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of DC Shunt Motor electromagnetic torque developed is Proportional to the armature current. Inversely proportional to the armature current. None of above. Proportional to the square of armature current. Proportional to the armature current. Inversely proportional to the armature current. None of above. Proportional to the square of armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase slip-ring induction motor, brushes are connected to 3 - Φ AC supply. external star-connected resistors. DC supply. equalizing coils. 3 - Φ AC supply. external star-connected resistors. DC supply. equalizing coils. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If residual magnetism of a shunt generator is destroyed accidentally it may be restored by connecting its shunt field to a DC source. to earth. in reverse. to an AC source. to a DC source. to earth. in reverse. to an AC source. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines R1 is the resistance of the primary winding of the transformer. The turn ratio in terms of primary to secondary is K. Then the equivalent resistance of the primary referred to secondary is R1 /K² R1 /K K×R1 K²R1 R1 /K² R1 /K K×R1 K²R1 ANSWER DOWNLOAD EXAMIANS APP
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