480v 3 phase to 600v 3 phase

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I would like a drawing for wiring two single phase (120v 240v) transformers so I can power a Canadian machine that needs 600v

I do not believe that can be done, both from a practical and a code compliant standpoint. Using a buck boost transformer may be a cost effective option although your voltage change is a bit on the high side. Someone more knowledgeable in this area will likely chime in.
 

augie47

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Likewise, I'm not a "transformer" man so take that into account, however, here is a diagram (obviously ignore the voltage) of (2) single phase transformers used on 3 phase systems/
May help.

transf.png

opps Besoeker is on site.. he can help you far better than I
 

Besoeker

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Likewise, I'm not a "transformer" man so take that into account, however, here is a diagram (obviously ignore the voltage) of (2) single phase transformers used on 3 phase systems/
May help.

View attachment 11594

opps Besoeker is on site.. he can help you far better than I
Maybe not - I missed the 3-phase in the title!
But is the supply three phase?

If so, I'd go for a simple double wound three phase unit.
240V in, 600V out.
 

iceworm

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I would like a drawing for wiring two single phase (120v 240v) transformers so I can power a Canadian machine that needs 600v

So the transformers you have are NOT single phase?

The transformers i will be useing both have X1, X2, X3, X4, H1, H2, H3, H4
So they are 3 phase transformers? And you have two of them.

To get meaningful answers, we will need the transformers nameplate data

Are they are Wye-Wye?

What is the primary voltage?,

What is the secondary voltage?

ice
 

GoldDigger

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If you have transformers designed for 120/240 input and less than 480V output, they will do you no good, since you cannot connect them to 480V.
Now with isolation type three phase transformers you cannot necessarily construct a boost configuration, depending on the configuration of the output windings.
Given two single phase 480 to 120 transformers and a corner grounded delta input you can construct a 600V corner grounded open delta. But would you really want to do that?
 
this worked

this worked

i am not the one that took this all apart, but it did work, and the two single phase 120v 240v transformers took 480v and increased the voltage to 600v (adding 120v). anyone who knows i would really like to know how to do this (buck BOOST) thanks!
 

jim dungar

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i am not the one that took this all apart, but it did work, and the two single phase 120v 240v transformers took 480v and increased the voltage to 600v (adding 120v). anyone who knows i would really like to know how to do this (buck BOOST) thanks!

Look at page 6 for
"Two Units Connected as Open-Delta Auto Transformer for Three Phase Operation for 600?480; 480?600; 480?380;"
http://static.schneider-electric.us/docs/Electrical%20Distribution/Low%20Voltage%20Transformers/Energy%20Efficient-NEMA%20TP1/7400HO9501.pdf
 
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GoldDigger

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Please be more specific about the transformers.
Are they 480/240 input, 240/120 output depending on series parallel connection of the input and output windings? Just saying 120/240 either does not give enough information or specifies a transformer that cannot work.
 
480 to 575

480 to 575

after wiring the two single phase transformers (as per square D diagram) I was wrong about the H side , there are only H1 and H2 on these transformers; 480 in but only 508 out,and changing the taps had no change in output, this is not within 10%, i was told the motor was 600v but the motor name plate calls for 575. in the diagram suggested in a recent reply to my situation I followed the diagram for 480 to 575, it seemed strange to connect phase B 480v to phase B 575v only, anyone know about solving this problem ? thanks
 

kwired

Electron manager
Location
NE Nebraska
after wiring the two single phase transformers (as per square D diagram) I was wrong about the H side , there are only H1 and H2 on these transformers; 480 in but only 508 out,and changing the taps had no change in output, this is not within 10%, i was told the motor was 600v but the motor name plate calls for 575. in the diagram suggested in a recent reply to my situation I followed the diagram for 480 to 575, it seemed strange to connect phase B 480v to phase B 575v only, anyone know about solving this problem ? thanks
Do you have the correct transformer? Remember the HV terminals are the higher voltage side whether you are bucking or boosting and has nothing to do with which side is the input vs output for the application.

The connection of B phase input to B phase output is a normal thing for autotransformers - that is part of the definition of autotransformer is one conductor is common to both primary and secondary of the transformer a separately derived system has no connection between primary and secondary other then grounding connections, but neither side in those cases depends on the other side for proper operation. Voltage measured at output of properly selected and connected units will be ~575 from phase to phase. Voltage to ground will not be balanced like it would be for a true separately derived wye system - but you are not using this to supply line to neutral loads so it doesn't matter.
 

Besoeker

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UK
Of course you would, it's not your own money you are spending. :D
We build kit from component level so it is our money in most cases. Fixed price at that so, if we can build it cheaper and still be spec compliant, we make a better margin.

:)
 
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