240/120 Delta to 208y/120?

[chris kennedy]

Hello all, hope this finds you well.

I am being told the tranny bank below can't be rewired for 208y. Currently it is wired for 4 wire 240 delta. It would seem to me the primary to secondary winding ratio would allow the primary taps to be wired for either.

Please advise.

Thanks

[chris kennedy]

This is FPL BTW.

[lewy]

This bank can be changed from a 240 delta to a 120/208 wye. You would just have to parallel the secondary windings to make each transformer 120, or ground the x2 and turn each transformer back to 120/240 and just use 1 leg from each transformer, but you would only get half the KVA of each transformer.

[chris kennedy]

or ground the x2 and turn each transformer back to 120/240 and just use 1 leg from each transformer, but you would only get half the KVA of each transformer.

The tranny wouldn't like this set up would it? Unbalanced to the max.

[lewy]

The tranny wouldn't like this set up would it? Unbalanced to the max.

You asked if it can be rewired to 120/208 and the answer is yes it can. You would obviously have to change the connections and the customer would have some work to do, as far as unbalanced only if the customers load was unbalanced.

[chris kennedy]

You asked if it can be rewired to 120/208 and the answer is yes it can. You would obviously have to change the connections and the customer would have some work to do, as far as unbalanced only if the customers load was unbalanced.

Cool bet, thank you.

Would I still lose ½kva? My maths says if those trannys are 75's that would give me 100A 3Ø 208y/120

[lewy]

Depending on how you hook it up you either get 225KVA or 112

[Orgnizdlbr]

You asked if it can be rewired to 120/208 and the answer is yes it can. You would obviously have to change the connections and the customer would have some work to do, as far as unbalanced only if the customers load was unbalanced.

Yup, lewy is right on.....

[Lineman North Florida]

Take the lids off and split the pots, AC/BD leaving one bushing as you're dummy bushing, surely FP&L has a standard spec for which bushing is you're dummy bushing I would think, not real sure why someone would tell you that it could not be done unless there is something else that I'm not seeing.

[Rob]

Take the lids off and split the pots, AC/BD leaving one bushing as you're dummy bushing, surely FP&L has a standard spec for which bushing is you're dummy bushing I would think, not real sure why someone would tell you that it could not be done unless there is something else that I'm not seeing.

Yup..Most places it's X1. I like the White spool on the down guy!