Electrical Machines The damper windings also called the squirrel cage windings or damper grids are provided in a synchronous motor to make it self starting. consists of short-circuited copper bars embedded in the field pole faces. are provided on the stator for improving power factor. both (A) and (B). are provided in a synchronous motor to make it self starting. consists of short-circuited copper bars embedded in the field pole faces. are provided on the stator for improving power factor. both (A) and (B). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider a separately excited DC motor. If the field current is increased while the armature terminal voltage is held constant, then speed of the motor will Decrease.d remains same. increase. none of these. Decrease.d remains same. increase. none of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will be the eddy current loss if the supply frequency of a transformer becomes double? Remains same. Doubled. Four times. Eight times. Remains same. Doubled. Four times. Eight times. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Compensating winding is placed in the armature core All of these pole shoe main field armature core All of these pole shoe main field ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 2, 4 1, 4 1, 3 2, 3 2, 4 1, 4 1, 3 2, 3 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 15.9 Ω 31.9 Ω 15.1 Ω 31.1 Ω 15.9 Ω 31.9 Ω ANSWER DOWNLOAD EXAMIANS APP
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