why 30kva ups buzzing(hamming) sound?

2 Answers   Madhya Pradesh Electricity Board MPEB,

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what are different types of alternator and discuss about the methods of cooling

16 Answers   Bhel, Jindal, L&T, Nalco, Vedanta,

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how to measure the transformer resistance values(dyn11)?and howmuch the minimum value?

0 Answers  

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if the field circuit of a d.c. shunt motor running without load gets opened, then the motor will

3 Answers  

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How can I calculate the require lumen of a room. If I use Tube Light (40 W), Or 100 W incandescent lamp. Please give detail answer.

1 Answers  

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We have 2 Nos. Transformer with the capacity of 2000KVA and 1250 KVA and currently using only one 2000KVA T/R during operational hours while non- operational hous 1250 KVA T/R also used to reduce T & D losses. Similarly, 2 capacitor bank of 500KVAR and 300 KVAR also installed to balance reactive power. Now problem is around 1000 KW load PF is not maintaning 0.99 as 350 KVAR capacitor is in healty condtion. Now the PF is maintain 0.95 to 0.96.

2 Answers  

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Why we specify TNC switch with 1NO 1NC ,2NO 2NC ? how we get connection.?

0 Answers  

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what is PI value and its significance for insulation testing?

3 Answers  

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What is the difference between KW & KVA ?

9 Answers  

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show me the diagram of three phase wiring and also tell me hoe to take the readings of megger testing

2 Answers  

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Can we loop AC neutral wire with DC neutral wire?

5 Answers   ABB,

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how are reversing the direction of dc motor

0 Answers  

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