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#127554 08/23/01 10:51 PM
Joined: Oct 2000
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sparky Offline OP
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Ok, We all know 2 X-formers and 3 hots can do an open delta, but.......
Can 3 X-formers and 2 hots be configured into some sort of 3 phase arrangement?

According to one source , this is called a 'scotch-something...'

[Linked Image]

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#127555 08/24/01 08:38 PM
Joined: Mar 2001
Posts: 2,056
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You are referring to a Scott connected configuration, in which a 3 phase primary is connected to two transformers in such a manner that 2 phase power is availableon the secondary. This information is available in McGraw-Hill's "American Electricians Handbook"

#127556 08/28/01 08:58 PM
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sparky Offline OP
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hmm;
i see it in the index, but not in the book, go figure.... [Linked Image]

#127557 08/28/01 09:33 PM
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Quote
Originally posted by sparky:
hmm;
i see it in the index, but not in the book, go figure.... [Linked Image]

Sparky,
What edition do you have? I'm home and my 11th edition discusses this beginning on page 5-55. There is a diagram on page 5-57. When I go in tomorrow, I'll check my other(newer) edition.

#127558 08/28/01 09:54 PM
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sparky Offline OP
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well I have a 13th, the index says it's at 5-92 to 5-94, which is just a lot of stuff about drying X-formers

#127559 08/29/01 07:21 AM
Joined: Mar 2001
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Quote
Originally posted by sparky:
well I have a 13th, the index says it's at 5-92 to 5-94, which is just a lot of stuff about drying X-formers
I have the 13th, also.
The index is confusing. It refers to sections, not pages. Look at SECTION 5-92 on PAGE 5.67

#127560 08/29/01 12:58 PM
Joined: May 2001
Posts: 717
G
Member
Designed to replace the Edison 3 wire DC hook up when swapped over to AC. Unless you work around coal mines (DC equipment runs on AC or batteries) you'll never see one. coal mine info is old, don't know if they still do it that way.

#127561 08/30/01 06:34 AM
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sparky Offline OP
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Look at SECTION 5-92 on PAGE 5.67
Dohh! Homer Simpson....
Ok, so I can't use my own book! [Linked Image]

anywho,
there it be, stange animal that it is. Could this be used in reverse? I.E.- get 3 phase 208V out of 2--4160V high legs?
that was the description I got from my 'source'

#127562 08/30/01 08:51 AM
Joined: Jul 2001
Posts: 599
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JBD Offline
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According to my engineering books the Scott connection is normally used for 2-phase to 3-phase conversion. If used in a 3 to 2 conversion the transformer output needs to be reduced to 86.6% of the combined single-phase ratings.

#127563 08/30/01 08:57 PM
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sparky Offline OP
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JBD,
can you elaborate?
the particular situation here was a linesman stating that 2 out of 3 phases were available at a job, and 3 ph was created via this 'Scott' configuration.

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