Electrical Machines What is the necessity of copper brushes in a dc motors? To convert alternating supply current to direct current. To absorb the mechanical shocks produced during running condition. None of these. To increase the flux cutting by the rotor. To convert alternating supply current to direct current. To absorb the mechanical shocks produced during running condition. None of these. To increase the flux cutting by the rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following will vary the maximum torque? None of these both 1 and 2 rotor resistance R rotor reactance X None of these both 1 and 2 rotor resistance R rotor reactance X ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In shapers and slotters which motor are preferred? Slip ring IM. Synchronous motor. Squirrel cage IM. Double cage motor. Slip ring IM. Synchronous motor. Squirrel cage IM. Double cage motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the actual arrangement of series wound generator? Armature winding is in series with load. Armature and field both are parallel. Armature and field both are in series with the load. Armature and field both are connected. Armature winding is in series with load. Armature and field both are parallel. Armature and field both are in series with the load. Armature and field both are connected. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Voltage across the open circuited field termninals of a synchorous machine under slip test is DC. DC of slip frequency. AC of supply frequency. A modulated supply frequency AC voltage with slip frequency envelop. DC. DC of slip frequency. AC of supply frequency. A modulated supply frequency AC voltage with slip frequency envelop. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of a 3 - Φ induction motor is clockwise when it is supplied with 3 - Φ sinusoidal voltage having phase sequence A - B - C. For counterclockwise rotation of motor, the phase sequence of the supply should be B - C - A. C - A - B. B - C - A or C - A - B. A - C - B. B - C - A. C - A - B. B - C - A or C - A - B. A - C - B. ANSWER DOWNLOAD EXAMIANS APP