Electrical Machines In a loaded DC generator, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will deteriorate with fall of terminal voltage. deteriorate with rise in terminal voltage. improve with fall of terminal voltage. improve with rise in terminal voltage. deteriorate with fall of terminal voltage. deteriorate with rise in terminal voltage. improve with fall of terminal voltage. improve with rise in terminal voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Direct-on-line (DOL) starters are not suitable for starting large DC motors, because the motor may run away. the motor may not start. the starting torque becomes low. the starting current will be enormously high. the motor may run away. the motor may not start. the starting torque becomes low. the starting current will be enormously high. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed regulation of a DC motor is given as (NfL − NnL)/NnL. NnL/NfL. NnL − NfL. (NnL − NfL)/NfL. (NfL − NnL)/NnL. NnL/NfL. NnL − NfL. (NnL − NfL)/NfL. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two of supply terminals to a 3 - Φ induction motor get interchanged during re-connection after normal maintenance. When switched on the supply, the motor will rotate in the same direction as before maintenance. not start at all. rotate in direction opposite to that before maintenance. get heated and damaged. rotate in the same direction as before maintenance. not start at all. rotate in direction opposite to that before maintenance. get heated and damaged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The results of a slip test for determining direct axis (Xd) and quadrature axis (Xq) reactances of a star connected salient pole alternator are given below Phase values: Vmax = 108 V ; Vmin = 96 V Imax = 12 A ; Imin = 10 A Hence the two reactances will be Xd = 9.6Ω and Xq = 9Ω Xd = 10.8Ω and Xq = 8Ω Xd = 9Ω and Xq = 9.6Ω Xd = 8Ω and Xq = 10.8Ω Xd = 9.6Ω and Xq = 9Ω Xd = 10.8Ω and Xq = 8Ω Xd = 9Ω and Xq = 9.6Ω Xd = 8Ω and Xq = 10.8Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor has the highest power factor at full load? Resistance split phase Capacitor run Capacitor start Shaded pole Resistance split phase Capacitor run Capacitor start Shaded pole ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS