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A synchronous machines has higher capacity for (1) Leading power factor (2) Lagging power factor (3) Does not depend upon the power factor of machine (4) None of the above 

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asked Apr 11, 2018 in Electrical Engineering by Shimroz123
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asked Apr 5, 2018 in Electrical Engineering by Shimroz123
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asked Apr 5, 2018 in Electrical Engineering by Shimroz123
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asked Jun 4, 2018 in Synchronous machine by Shimroz123
1 answer 16 views

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asked Apr 12, 2018 in Electrical Engineering by Shimroz123
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asked Apr 5, 2018 in Electrical Engineering by Shimroz123
0 answers 23 views

A Power system has a total load of 1260 MW at 50 Hz. The load varies 1.5% for every 1% change in frequency. Find the steady state frequency deviation, when a 60 MW load is suddenly dripped if there is no speed control.  (A) 1.667 Hz (B) 50 Hz (C) No change (D) 3.32 Hz 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
1 answer 22 views

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asked Mar 31, 2018 in Electrical Engineering by Shimroz123
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asked Mar 31, 2018 in Electrical Engineering by Shimroz123
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In dc machines, the armature windings are placed on the rotor because of the necessity for  (1) electromechanical energy conversion (2) generation of voltage (3) commutation (4) development of torque

asked May 1, 2018 in Electrical Machine by Shimroz123
1 answer 66 views

For protection of rotating machines against lightning surges _______ is used.  (1) lightning arrester (2) capacitor (3) combination of lightning arrester and capacitor (4) lightning conductor and arrester

asked Apr 30, 2018 in Switchgear And Protection by Shimroz123
1 answer 15 views

Which of the following relation is incorrect? A) capacity factor = utilization factor x load factor B) load factor x maximum load = average load C) demand factor x connected load = maximum demand D) none of these

asked Jun 17, 2018 in Electrical Engineering by Shimroz123
1 answer 31 views

Breaking capacity of a circuit breaker is usually expressed in terms of  (1) Ampere (2) Volts (3) MW (4) MVA

asked Apr 30, 2018 in Electrical Engineering by Shimroz123
1 answer 23 views

When a V-V three phase transformer system is converted into a Δ-Δ system, increase in capacity of the system is (A) 86.6% (B) 50% (C) 57.7% (D) 73.2%

asked Apr 28, 2018 in Electrical Engineering by Shimroz123

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