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The demagnetizing AT/pole of a 4-pole dc generator is 480. The number of conductors is 480 and the current in each conductor is 40 A. Then the required brush shift in mechanical degrees (A) 9° (B) 7° (C) 5° (D) 3° 

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For a fault at the terminals of a synchronous generator, the fault current is maximum for a  A) 3-phase fault B) 3-phase to ground fault C) Line to ground fault D) Line to line fault

asked May 17, 2018 in Synchronous machine by Shimroz123
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For a fault at terminals of the synchronous generator, the fault current is maximum for a:  (A) Three phase fault (B) Double line to ground fault (C) Line to line fault (D) Line to ground fault  

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A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50 Hz source, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor is  (A) 100 (B) 98 (C) 52 (D) 48

asked May 17, 2018 in Induction Machine by Shimroz123
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A 200 V dc motor takes a field current of 2 A to generate a back emf of 180 V. If the field winding resistance is 80 Ω, the resistance of the shunt field regulator is (A) 10 Ω (B) 20 Ω (C) 100 Ω (D) 180 Ω

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A dc shunt generator has a speed of 800 rpm when delivering 20 A to the load at the terminal voltage of 220V. If the same machine is run as a motor it takes a line current of 20A from 220V supply. The speed of the machine (in rpm) will be:  (A) 800 (B) more than 800 (C) less than 800 (D) none of the above

asked Apr 9, 2018 in Electrical Engineering by Shimroz123

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