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Anonymous Poster

scott-t transformer

03/06/2008 9:05 AM

what alternations are to made for scott-t transformer to give output 2-phase of 120 apart not of 90 degree.

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Guru
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#1

Re: scott-t transformer

03/09/2008 6:51 PM

Hello Guest,

The Scott-t transformer arrangement is now not commonly used, and it is well over 40 years since I worked on one, in a High Voltage Test Laboratory.

I have never had to do what you are asking, and wonder at the application you have in mind, for requiring the 120 degrees phase difference.

My estimate would be with one of the 2 phase windings an inductor in series with the load.

With the other 2 phase winding, place a capacitor in series with the load.

You would require some calculation to achieve the result you require.

Trust that has assisted you.

Should you need further help, reply back here with

Kind Regards....

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Guru
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#2

Re: scott-t transformer

03/10/2008 6:43 AM

I don't completely understand your question either. Are you asking what is different about a Scott-Tee transformer compared to a "regular" transformer? That answer would be that the windings are different. You can use an image search function such as Google to see the configuration.

But I also am concerned as to why you are asking. 2 phase power is almost unheard of now. Hopefully you are not making the common mistake of assuming that a power system with 2 "hot" legs is 2 phase, it is NOT. That is called 1 (single) phase power, and a Scott-Tee transformer is NOT the way to convert 1 phase to 3 phase, as many uninformed people seem to think (and continually post in DYI forums).

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Anonymous Poster
#3

Re: scott-t transformer

07/30/2009 5:32 PM

If, for some reason, you wanted to have 2-phase power in which the 2 sine waves were offset by 120 degrees rather than 90 degrees, All you would need to do is connect 2 single phase transformers to a 3 phase source without inter-connecting the secondaries. The primaries should connect to 2 different phases (A-B & B-C for instance). Each secondary coil will follow the phase angle of it's respective primary, so they'll be offset by 120 degrees!

If one end of one secondary coil is connected to one end of the other secondary coil, you will have an open-delta situation, which gives you 3-phase at 57.7% capacity.

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Anonymous Poster
#4

Re: scott-t transformer

11/25/2009 6:35 AM

you have to make v connected transformer

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