Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. Find the speed of stator magnetic field with respect to rotor? 30 rpm 1470 rpm 1500 rpm zero 30 rpm 1470 rpm 1500 rpm zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The stator frame in an induction motor is used to 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. protect the whole machine. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase slip-ring induction motor, brushes are connected to external star-connected resistors. 3 - Φ AC supply. DC supply. equalizing coils. external star-connected resistors. 3 - Φ AC supply. DC supply. equalizing coils. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ideal value of voltage regulation of a device is? ∞ 0 a positive finite value a finite negative value ∞ 0 a positive finite value a finite negative value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In double cage induction motor, the inner cage offers high resistance and high reactance. low resistance and high reactance. high resistance and low reactance. low resistance and low reactance. high resistance and high reactance. low resistance and high reactance. high resistance and low reactance. low resistance and low reactance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 1, 2, and 3 2, 3 and 4 1 and 3 1, 2 and 4 1, 2, and 3 2, 3 and 4 1 and 3 1, 2 and 4 ANSWER DOWNLOAD EXAMIANS APP
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