Electrical Machines In a star - delta starting of an IM resistance is inserted in the rotor. line voltage is 57.7 % of stator voltage. applied voltage per stator phase is 57.7 % of a line volt reduced voltage is applied to the stator. resistance is inserted in the rotor. line voltage is 57.7 % of stator voltage. applied voltage per stator phase is 57.7 % of a line volt reduced voltage is applied to the stator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The slip of an induction motor during DC rheostatic braking is 2 + s. 2 - s. 1 - s. s. 2 + s. 2 - s. 1 - s. s. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 ,V 15 , kW 100 rpm shunt motor with armature resistance of 0.25 , W has a rated line current of 68 A and a rated field current of 2.2 A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8 A and a field current of 1.8 A is 36.36% increase 36.36% increase 36.36% decrease 18.18% increase 36.36% increase 36.36% increase 36.36% decrease 18.18% increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm and rotor input power is 2KW. Find the rotor copper loss? 40W 100W 60W 80W 40W 100W 60W 80W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4, 5 2, 3, 4 1, 2, 3 2, 3 ,5 2, 3, 4, 5 2, 3, 4 1, 2, 3 2, 3 ,5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In speed control of DC shunt motor by varying field flux, what may be the value of field regulator? 0.2 ohm 2 ohm. 10 ohm 100 ohm 0.2 ohm 2 ohm. 10 ohm 100 ohm ANSWER DOWNLOAD EXAMIANS APP