Electrical Machines In IM the rotor lamination can be ________________ than stator laminations. sipper. thicker. rotor can not have any laminations. thinner. sipper. thicker. rotor can not have any laminations. thinner. 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 4 1, 2, and 3 1 and 3 2, 3 and 4 1, 2 and 4 1, 2, and 3 1 and 3 2, 3 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Neglecting all losses, the developed torque (T) of DC separately excited motor, operating under constant terminal voltage is reduced to its output power (P) as T ∝ √P. T is independent of P. T2 ∝ P3. T ∝ P. T ∝ √P. T is independent of P. T2 ∝ P3. T ∝ P. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ induction motor draws an current of 50 A from mains when starts by direct switching. If an auto transformer with 60 % tapping is used for starting the current drawn from the mains will be 36. 80. 50. 18. 36. 80. 50. 18. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A three phase 400 V, 6 pole, 50 Hz, squirrel cage induction motor is running at a slip of 5%. The speed of stator magnetic field with respect to rotor magnetic field and speed of rotor w.r.t stator magnetic field are zero , - 50 rpm. 1000 rpm, - 50 rpm. zero, 950 rpm. 1000 rpm, 950 rpm. zero , - 50 rpm. 1000 rpm, - 50 rpm. zero, 950 rpm. 1000 rpm, 950 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the reason for stationary armature essential in alternators above 5 KVA? Collecting of large current is simple. Operating cost is less. All of these Insulation requirement is less. Collecting of large current is simple. Operating cost is less. All of these Insulation requirement is less. ANSWER DOWNLOAD EXAMIANS APP