Answer / Nirankar Awasthi

Advantages of DC motors include: 1) Easy control of speed by varying the field current or armature voltage. 2) High torque at low speeds, making them suitable for applications requiring high starting torque. Disadvantages include: 1) Complex construction due to the presence of a commutator and brushes. 2) Inefficiency at light loads due to high copper loss.

Why Cables are always circular and not square or rectangular?

3 Answers  

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how to calculate the no. of earth pits required for an electrical installation?

1 Answers   Mepax,

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What happen if 200 KVAR capacitor connected to power continuesly?

1 Answers  

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How to calculate the input cable rating for 10kva ups (3phase input and single phase output and also 3phase output, battery rating 65Ah)provide the formula also.thnx

1 Answers   Bhel,

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what are the deffects for failure of PLC?

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1. What is the difference between ac induction motor and ac synchronous motor?

11 Answers  

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In a star-star connected h.t transformer why we use NGR on the secondary (l.t)side.

3 Answers   Star, TATA,

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what is real power and reactive power?

3 Answers  

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For polarity test on a 11/3.3kV 2.5MVA delta-star Unit Auxiliary transformer,415V 3-phase supply was applied at the HV. Connection between Aa was made with a 2.5mm cable. As soon as power was switched on the cable caught fire and burnt. This test was then abandoned. It is noteworthy to say that a similar cable was also used in a similar transformer for the same. The cable did not burn and test was successfully completed with good result. What is wrong? Please, help me out.

3 Answers  

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why some transmission lines have 7 wires n why some have 3 n 4??

3 Answers  

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is emf is indued if dc is passed through coil

5 Answers  

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what is p.s impedance measurement test in earthing transformer?

1 Answers   Greenko,

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