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suhasdh
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Why Transformer Rratings are Always Calculated in VA (KVA/MVA etc.)?

02/24/2012 4:06 AM

Why transformer ratings are always calculated in VA (KVA/MVA etc.)?
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SolarEagle
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#1

Re: Why transformer ratings are always calculated in VA (KVA/MVA etc.)?

02/24/2012 4:18 AM

How would you rate them?

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Crabtree
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#2

Re: Why transformer ratings are always calculated in VA (KVA/MVA etc.)?

02/24/2012 5:15 AM

Would you like them in horsepower?

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MACA
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#3

Re: Why transformer ratings are always calculated in VA (KVA/MVA etc.)?

02/24/2012 5:20 AM

Do you mean instead of Watts?
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suhasdh
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#4

Re: Why transformer ratings are always calculated in VA (KVA/MVA etc.)?

02/24/2012 6:25 AM

Yes MACA. You are right.

Basically power, motor ratings are always either in HP(horse power) or KW(Kilo Watt). But why transformer rating is always in VA and not in HP or KW.

A humble request : If any of you know the right answer then & then only reply.

The questions asked here by anyone may look like cheap or stupid for you but that ones might be important for those who didn't know the answers.

So think & then reply.
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kvsridhar
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#5
In reply to #4

Re: Why transformer ratings are always calculated in VA (KVA/MVA etc.)?

02/24/2012 7:18 AM

i admire your philanthropic attiude, but this has been asked and answered several times. You can search for the earlier threads by using the search option to the right.

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MACA
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#6

Re: Why Transformer Rratings are Always Calculated in VA (KVA/MVA etc.)?

02/24/2012 7:52 AM

To help you along without spoon feeding you, try looking up power factor. (cos phi)
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spradhan
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#7

Re: Why Transformer Rratings are Always Calculated in VA (KVA/MVA etc.)?

02/24/2012 8:41 AM

You are aware that, transformer is an intermediate device between the source of power and the consumers.

Each of the consumers may have different power factors depending upon the nature of loads thereof.

The rating of the loads (viz.motors,heaters,lamps etc ) are given in kW since power factors of individual loads are also specified by the designer/ manufacturer.But, power factor of the transformer will depend upon the resultant effect of all the loads it feeds which will vary depending upon the no. and type of loads it caters to at a particular moment.

Hence,transformer ratings are always given in VA/kVA/MVA.

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Crabtree (1); kvsridhar (1); MACA (2); SolarEagle (1); spradhan (1); suhasdh (1)

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