Electrical Machines A 3 - Φ, 4 pole IM is supplied from a 50 Hz source. Calculate rotor frequency when rotor runs 600 rpm? 35 Hz. Can be determined. 20 Hz. 30 Hz. 35 Hz. Can be determined. 20 Hz. 30 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The output voltage of a DC generator is E = V + Ra. E = V + IaRa. E = V – IaRa. E = V + Ia. E = V + Ra. E = V + IaRa. E = V – IaRa. E = V + Ia. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators, the brushes remain in contact with conductors which lie under south pole. lie in the inter polar gaps. there is no hard and fast rule for this. lie under north pole. lie under south pole. lie in the inter polar gaps. there is no hard and fast rule for this. lie under north pole. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? PN / 2 Hz. 120N / P Hz. 120 / PN Hz. 120P / N Hz. PN / 2 Hz. 120N / P Hz. 120 / PN Hz. 120P / N Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The oscillation in a synchronous motor can be damped out by oscillation cannot be damped. running the motor on leading power factors. providing damper bars in the rotor pole faces. maintaining constant excitation. oscillation cannot be damped. running the motor on leading power factors. providing damper bars in the rotor pole faces. maintaining constant excitation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor when started on no load does not accelerate up to full speed but runs at 1/7th of the rated speed. The motor is said to be cogging. plugging. locking. crawling. cogging. plugging. locking. crawling. ANSWER DOWNLOAD EXAMIANS APP