Electrical Machines When the rotor speed, in a synchronous machine, becomes more than the synchronous speed during hunting, the damper bars develop induction motor torque. induction generator torque. synchronous motor torque. DC motor torque. induction motor torque. induction generator torque. synchronous motor torque. DC motor torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To have sparkless commutation, the armature reaction effect in a DC machine is neutralized by 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. compensating winding and commutating poles. fixing the brush axis inline with the pole axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is/are the necessary conditions for parallel operation of alternators? Terminal voltage is same Both 1and 2 Frequency should be same Speed of alternators should be same Terminal voltage is same Both 1and 2 Frequency should be same Speed of alternators should be same ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the shunt resistance component equivalent circuit obtained by no load test of an induction motor representative of ? windage and friction loss core loss only Copper loss both 1 and 2 windage and friction loss core loss only Copper loss both 1 and 2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Slip speed is the difference of synchronous speed and actual rotor speed. sum of synchronous and rotor speeds. difference of actual rotor speed and synchronous speed. half of the sum of synchronous and rotor speeds. difference of synchronous speed and actual rotor speed. sum of synchronous and rotor speeds. difference of actual rotor speed and synchronous speed. half of the sum of synchronous and rotor speeds. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole wave wound dc motor having flux per pole of 9.56 X 10-3 Wb contains 460 armature conductors with armature resistance of 0.6 ohm. Calculate the starting current flowing through the armature if the supply voltage is 240 volt. 0.5 Amp. 400 Amp. 320 Amp. 800 Amp. 0.5 Amp. 400 Amp. 320 Amp. 800 Amp. ANSWER DOWNLOAD EXAMIANS APP