Electrical Machines To have sparkless commutation, the armature reaction effect in a DC machine is neutralized by compensating winding and commutating poles. fixing the brush axis inline with the pole axis. shifting the brush axis from GNA to MNA. increasing field excitation. compensating winding and commutating poles. fixing the brush axis inline with the pole axis. shifting the brush axis from GNA to MNA. increasing field excitation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The results of a slip test for determining direct axis (Xd) and quadrature axis (Xq) reactances of a star connected salient pole alternator are given below Phase values: Vmax = 108 V ; Vmin = 96 V Imax = 12 A ; Imin = 10 A Hence the two reactances will be Xd = 9.6Ω and Xq = 9Ω Xd = 8Ω and Xq = 10.8Ω Xd = 10.8Ω and Xq = 8Ω Xd = 9Ω and Xq = 9.6Ω Xd = 9.6Ω and Xq = 9Ω Xd = 8Ω and Xq = 10.8Ω Xd = 10.8Ω and Xq = 8Ω Xd = 9Ω and Xq = 9.6Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Capacitor in split phase induction motor is used to reduce the harmonics. start the motor. improve the starting torque. improve the power factor. reduce the harmonics. start the motor. improve the starting torque. improve the power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor wound rotor motor is mainly is used in application where power factor is less. less costly motor is not required. low starting torque. high starting torque. power factor is less. less costly motor is not required. low starting torque. high starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by a 220 V DC series motor of armature resistance 0.5 Ω and back emf of 200 V is 400 A. 440 A. 44 A. 40 A. 400 A. 440 A. 44 A. 40 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V DC series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 ohms. The value of resistance which must be added to obtain rated torque at 1000 rpm is 1.9 ohms. 2.2 ohms. 5.7 ohms. 6 ohms. 1.9 ohms. 2.2 ohms. 5.7 ohms. 6 ohms. ANSWER DOWNLOAD EXAMIANS APP