Answer / bharath kumar

TRANSFORMERS WORKS ON THE PRINCIPLE OF MUTUAL INDUCTION
WHICH IS A PURELY AC PHENOMENON,HENCE WORKS ONLY FOR AC
SUPPLY NOT FOR DC

Answer / wareagle

Is there a question. Transformers do not use a DC supply.

Answer / kj

Induction requires a conductor to move through a magnetic
field.

In a transformer the conductor is stationary and the
magnetic field is moved by the rise and fall of voltage
from the sine wave. This requires a change in voltage. With
DC the only change would be when it is turned on and turned
off. So pure DC will not work with a transformer.

The second thing is that with AC there will be a winding
resistance and an impedence as well to limit the current
flow. With DC there will only be winding resistance. This
could cause the windings to over heat if the same voltage
is applied.

Answer / avi2neha

There will be dead short circuit. due to dead short circuit transformer will get burn due to over heating of transformer winding.

what is the formula for converting dc power(watt) to ac power (watt)?

3 Answers   ABB,

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There is one 40MVA oil cooled transformer (yet to commission), filled with 95% oil and we are trying to fill 5% Nytrogen in that transformer so that there should not be any foreign component inside. But even though there is no leakage, nytrogen is not withstanding inside transformer, within a day or two pressure guage is showing 0. Why is it soooo? Pls reply.

1 Answers  

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what is the use of providing earthing for tanks? i know for lightning we use earthing ? Here one of my ONGC project there is no need of lightning protection and there is no power connection near by tank in that situation also ONGC asking earthing for tanks but we didn't understanding why they asking earthing? is anybody tell exact answer?

4 Answers  

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How the Oil Surge Relay works? How it protect the OLTC?

3 Answers   JSL,

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Clearly Define Active,Reactive,Apparant power.Which applications used which power above metioned power?

9 Answers   Summit Power,

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what is a panel board?

1 Answers  

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difference between brush less & brush excitation in a generator?

1 Answers  

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Is there a possibility to use such a treshold voltage for the NMOS part of a CMOS circuit that during the switching it will start conducting only after the PMOS part will be already closed, by this eliminating the leakedge current? Please note, I'm not asking about the well bias in standby mode, but about the "antileakedge" measures during normal operation.

0 Answers  

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WHY WE CAN GENERATE POWER IN 3PHASE MODE ONLY NOT IN 4 OR 5 PHASE?

10 Answers  

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How to know of any cable size if there are not written on cabl?

0 Answers   APGenco, El Seif,

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how you connect the induction motor first in star and then delta in star-delta starter

1 Answers  

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Transformer rating=> 15/20 MVA.Why there are two raings? What should be the rating of the fuse at the secondary if the voltage level is 13.8KV/4.16KV?

1 Answers   Bhel,

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