boost 3phase load with 2 single phase xfmrs

[ibew441dc]

I hope I'm right on this one. (I'll try to keep it short)

Today I was engaged in a disagreement with a "building staff engineer'' about a piece of equipment they called my shop out to move to a new location.

The piece of equipment is a 3 phase 240vac paper shredder made in europe.
The building only has the means to supply 208 vac.

The building staff engineer built a boost station with 2 single phase transformers and claims that the european company told him how to hook it up and what it required.

I insisted that it was wired in error (at least to American standards). I told him in order to boost 208(3phase) to 240(3phase) he needed 3 single phase transformers not 2.

Am I correct, or do I have to eat crow.

 

[winnie]

Two is all that you need.

See http://www.sola-hevi-duty.com/products/transformers/pdfs/bboost/bbelectconnec.pdf

In the above, about half of the 3 phase connections are 'open delta' using two transformers.

-Jon

 

[ibew441dc]

Two is all that you need.

See http://www.sola-hevi-duty.com/products/transformers/pdfs/bboost/bbelectconnec.pdf

In the above, about half of the 3 phase connections are 'open delta' using two transformers.

-Jon

i'll buy that. Thanks

I guess the way I learned isn't the only way.Here goes the beak.

 

[ronaldrc]

This should be it.

 

[brian john]

Hopefully you were nice in trying to explain to him you thought he was wrong, Crow does not taste all that nice I am told.

 

[ibew441dc]

Hopefully you were nice in trying to explain to him you thought he was wrong, Crow does not taste all that nice I am told.

yeh i was nice, the good thing is that neither one of us were sure


Thats why I love this forum, it doesn't take long to learn something new

 

[coulter]

... Crow does not taste all that nice I am told.

It isn't bad - but then I've had a lot of practice

Eat it while it's warm.
Start with the tail - it only gets better.

carl

 

[peter d]

It isn't bad - but then I've had a lot of practice

Eat it while it's warm.
Start with the tail - it only gets better.

Use plenty of ketchup too.

 

[brian john]

One thing I have learned over the years is not to make statements that could lock me into a incorrect installations or directions.

I always use, I think, BUT let me research this. So many times I hear electricians make incorrect statements then argue themselves into a corner when asked to prove it.

 

[LarryFine]

I told him in order to boost 208(3phase) to 240(3phase) he needed 3 single phase transformers not 2.

Am I correct, or do I have to eat crow.

You are correct if the neutral is needed by the machine; the 240v rating suggests it is not, and the above responses are correct.

 

[resistance]

One thing I have learned over the years is not to make statements that could lock me into a incorrect installations or directions.

I always use, I think, BUT let me research this. So many times I hear electricians make incorrect statements then argue themselves into a corner when asked to prove it.

I agree !