Electrical Machines A 3 - Φ, 400 / 200 V, Y - Y connected wound rotor induction motor has 0.06 Ω rotor resistance and 0.3 Ω standstill reactance per phase. To make the starting torque equal to maximum torque of the motor the additional resistance required 0.78 Ω. 0.24 Ω. 0.66 Ω. 0.45 Ω. 0.78 Ω. 0.24 Ω. 0.66 Ω. 0.45 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A generator may loose residual magnetism due to over excitation. heating. any of these. vibrations. over excitation. heating. any of these. vibrations. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor has which of the following characteristics? Has a almost constant speed. Can be started easily without load. Has a poor torque. Has its field winding consinting of thick wire and less no of turns. Has a almost constant speed. Can be started easily without load. Has a poor torque. Has its field winding consinting of thick wire and less no of turns. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature resistance of a permanent magnet dc motor is 0.8 Ohm. At no load, the motor draws 1.5 A from a supply voltage of 25 V and runs at 1500 rpm. The efficiency of the motor while it is operating on load at 1500 rpm drawing a current of 3.5 A from the same source will be 59.2%. 88.8%. 57.1%. 48.0%. 59.2%. 88.8%. 57.1%. 48.0%. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two single-phase alternators operating in parallel have induced EMFs on open circuit of 230∠0° and 230∠10° volts and respective reactance of j2 Ω j3 Ω calculate the terminal voltage 150 V. 300 V. 223.V. 200 V. 150 V. 300 V. 223.V. 200 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In field flux method speed control of DC Motor is constant torque drive above the base speed. constant power drive above base speed. constant torque drive below the base speed. constant hp drive below the base speed. constant torque drive above the base speed. constant power drive above base speed. constant torque drive below the base speed. constant hp drive below the base speed. ANSWER DOWNLOAD EXAMIANS APP