Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.512. 0.443. 0.649. 0.573. 0.512. 0.443. 0.649. 0.573. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The damper windings also called the squirrel cage windings or damper grids consists of short-circuited copper bars embedded in the field pole faces. both (A) and (B). are provided in a synchronous motor to make it self starting. are provided on the stator for improving power factor. consists of short-circuited copper bars embedded in the field pole faces. both (A) and (B). are provided in a synchronous motor to make it self starting. are provided on the stator for improving power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines How can the synchronous speed of a 3 - Φ IM be varied? By varying the supply frequency. Both (A) and (B). By varying number of poles. By varying supply voltage. By varying the supply frequency. Both (A) and (B). By varying number of poles. By varying supply voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - φ induction motor running at full load which of these parameters is stationary with respect to the stator mmf wave? Both rotor and stator winding. Rotor mmf wave. Stator winding. Rotor winding. Both rotor and stator winding. Rotor mmf wave. Stator winding. Rotor winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Voltage regulation of transformer is given by (V2 - E2) / E2 (E2 - V2) / E2 (V2 - E2) / V2 (E2 - V2) / V2 (V2 - E2) / E2 (E2 - V2) / E2 (V2 - E2) / V2 (E2 - V2) / V2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor is suitable for frequent starting and stoppings? Capacitor start motor Capacitor start capacitor run motor All of these Resistance split phase motor Capacitor start motor Capacitor start capacitor run motor All of these Resistance split phase motor ANSWER DOWNLOAD EXAMIANS APP
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