Electrical Machines A DC series motor is running at rated speed without any additional resistance in series. If an additional resistance is placedin series, the speed of motor Oscillates around the rated speed. Decreases. Remains unchanged. Increases. Oscillates around the rated speed. Decreases. Remains unchanged. Increases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ward Leonard control provides speed control in both direction. below rated speed. in one direction only. above rated speed. in both direction. below rated speed. in one direction only. above rated speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The field system of an alternator is usually excited 250 / 250 V DC. 3 - Φ, 50 Hz and 400 V. 110 / 220 V AC. 230 V AC. 250 / 250 V DC. 3 - Φ, 50 Hz and 400 V. 110 / 220 V AC. 230 V AC. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 1, 3 1, 2, 3 and 4 3 only 1, 2 and 3 1, 3 1, 2, 3 and 4 3 only 1, 2 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Lap winding is prefered for which type of machines? high current and low voltage high current and high voltage low current and high voltage low current and low voltage high current and low voltage high current and high voltage low current and high voltage low current and low voltage ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In the 3-phase induction motor, the resultant flux is of a constant nature and is 1/2 times maximum value of flux due to any phase equal to φm, where φm is the maximum flux due to any phase 3 times maximum value of flux due to any phase 3/2 times maximum value of flux due to any phase 1/2 times maximum value of flux due to any phase equal to φm, where φm is the maximum flux due to any phase 3 times maximum value of flux due to any phase 3/2 times maximum value of flux due to any phase ANSWER DOWNLOAD EXAMIANS APP
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