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Member

Join Date: Apr 2012
Posts: 9

### Multiplication Factor

04/27/2012 10:56 AM

i having the multiplication factor of 17

for calculating HT amps to LT amps

how we took multiplication factor as 17 is there any formula????

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Pathfinder Tags: multiplication factor (blind formula)
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#1

### Re: multiplication factor

04/27/2012 10:59 AM

Because your HT to LT transformer's turns ratio could be 17. The formula is:

V1/V2 = N1/N2 = I2/I1

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#2

### Re: multiplication factor

04/27/2012 12:57 PM

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#3

### Re: multiplication factor

04/27/2012 9:57 PM

He just did.

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#4

### Re: multiplication factor

04/28/2012 12:10 AM

thanks a lot

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#5

### Re: multiplication factor

04/28/2012 12:23 AM

You're welcome.

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#6

### Re: multiplication factor

04/28/2012 12:59 AM

Obviously language is a barrier here.

We have to assume, since you did not give more information, that you are talking about the currents in the windings of a transformer, where HT means High Tension (High Voltage in American English), and LT means Low Tension (Low Voltage). Ignoring losses, the power out of a transformer is the same as the power in. Power is the product of Voltage and Current, so again ignoring losses, if there is a 17:1 Voltage ratio on your transformer (which would be obtained by having a 17:1 turns [windings] ratio), then the current ratio must be 1:17.

When Electricalexpert65 wrote "V1/V2 = N1/N2 = I2/I1" , he was essentially saying "The voltage ratio is the same as the turns ratio, and is the inverse of the current ratio."

A transformer must be wound with an appropriate number of turns on the primary and secondary windings to achieve the desired voltage ratio, and each winding must be made using wire of an appropriate cross section to carry the required current.

Apparently you are dealing with a transformer that has 17 times as many turns in one winding as it does in the other. The low voltage winding should have been done using wire having roughly 17 times the cross section of the wire used in the high voltage winding.

Of course there ARE losses in every transformer, so the actual current ratio will be a little different than the theoretical one.

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#7

### Re: Multiplication Factor

05/05/2012 3:12 AM

thanks a lot

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Off Topic (Score 5)