Answer / neha koul

The ac mains supply we get in our homes are not constant, this is variable i.e the frequency goes up and down, if we directly use the ac mains power many of our home elctrical appliances may get damaged, so we need a transformer which transforms the voltage and make it constant at some specific value due to electromagnetic induction and time varying magnetic field. The specific value of transformer depends on us that what value we want to give by stepping it up or stepping it down.

Answer / kumar.m

We need transformers for using step down / step up voltage.
and eddy current lossing .

in a live circuit with a light bulb such that the bulb is off by a switch, is the light glows if the switch 2 terminals are both touched by a mouse?

1 Answers  

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5MVA TRANSFORMER SUDDENLY FAIL WITH THE PRV TRIPPING AND LARGE AMOUNT OF OIL SPREAD OUT? SO IT CAME BACK WITH THE REPAIRING WITH REASON THAT IT FAILS BCOZ OF TRANSIENT EFFECT? SO PLZ EXPLAIN HOW DOES IT HAPPENED?

1 Answers  

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What is best method of Calculating Short Circuit current in power system network.

1 Answers  

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why we use the 100% and 95% stator earth fault protection for the synchronus generator ?

0 Answers   Operational Energy Group,

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what is the difference between bus-coupler and bus-riser

2 Answers  

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When measuring the Insulation resistance of a motor winding (winding to earth) using a megger meter, Applied voltage(1000V) was automatically reduced to 500V. and the measured insulation resistance values are also very low (in Kohm range) Can anyone give me a reason???

3 Answers  

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how df/dt relay operates & how it works?

1 Answers  

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Is it necessary to seperate the DG earth grid with Electricity Board earth grid for protecting the DG set. if yes why?

2 Answers   BARC,

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How does CT can measure the high value DC current?

4 Answers  

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what is electricity

4 Answers  

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Explain the function and difference of Restricted earth fault, simple earth fault and sensitive earth fault with connection diagram.

0 Answers   ABB,

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IF i have switchgear with busbar current rating of 1000Amp 35kA then is it necessary to have outgoing breaker kA rating to be equal to busbar kA rating?

6 Answers   L&T,

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