Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? 120N / P Hz. 120 / PN Hz. PN / 2 Hz. 120P / N Hz. 120N / P Hz. 120 / PN Hz. PN / 2 Hz. 120P / N Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The air gap between the yoke and armature is dc machine is kept very small to avoid over heating. to achieve a stronger magnetic field. All of these to avoid locking of the armature. to avoid over heating. to achieve a stronger magnetic field. All of these to avoid locking of the armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following speed control of DC motor the speed obtained is below than the rated speed? Armature circuit resistance control. Field resistance control. Any of above. Armature voltage control. Armature circuit resistance control. Field resistance control. Any of above. Armature voltage control. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The field system of an alternator is usually excited 250 / 250 V DC. 3 - Φ, 50 Hz and 400 V. 110 / 220 V AC. 230 V AC. 250 / 250 V DC. 3 - Φ, 50 Hz and 400 V. 110 / 220 V AC. 230 V AC. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC motor is laminated to reduce the eddy current loss. to reduce the hysteresis loss. to reduce the inductor. to reduce the mass. to reduce the eddy current loss. to reduce the hysteresis loss. to reduce the inductor. to reduce the mass. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Air core transformer as compared to iron core transformer, has less magnetic core loss. no magnetic core loss. more magnetic core loss. more copper loss. less magnetic core loss. no magnetic core loss. more magnetic core loss. more copper loss. ANSWER DOWNLOAD EXAMIANS APP