Electrical Machines Which of the following represents the operating region of slip in a 1-phase induction motor? -2 < S < 2 -1 < S < 1 0 < S < 1 0 < S < 2 -2 < S < 2 -1 < S < 1 0 < S < 1 0 < S < 2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer core is laminated to reduce eddy current loss. hysteresis loss. copper loss. both 1 and 2. eddy current loss. hysteresis loss. copper loss. both 1 and 2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 200 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 Ω. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is 1.06 0.87 0.96 0.95 1.06 0.87 0.96 0.95 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements, 2, 3 and 4 are correct 1 and 4 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct 2, 3 and 4 are correct 1 and 4 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The external resistance to be added in the armature circuit to limit the armature current to 125% of its rated value is 15.1 Ω 31.1 Ω 31.9 Ω 15.9 Ω 15.1 Ω 31.1 Ω 31.9 Ω 15.9 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if the field flux axis is ahead of the armature field axis in the direction of rotation, the machine operating is asynchronous generator. synchronous generator. synchronous motor. asynchronous motor. asynchronous generator. synchronous generator. synchronous motor. asynchronous motor. ANSWER DOWNLOAD EXAMIANS APP