Delta to Wye

[mannyb]

On a delta to Wye Transformer using 208 as primary and 277480 secondary. Where do you land the primary Xos or H ?

 

[LarryFine]

On a delta to Wye Transformer using 208 as primary and 277480 secondary. Where do you land the primary Xos or H ?

You don't. A delta primary should be connected like a 3ph motor: just three lines and an EGC.

the 480/277 H-0 is your secondary separately-derived neutral which needs a GEC connection.

 

[mannyb]

where does primary land on X or H

 

[mannyb]

You don't. A delta primary should be connected like a 3ph motor: just three lines and an EGC.

the 480/277 H-0 is your secondary separately-derived neutral which needs a GEC connection.

Where does primary land X or H

 

[jim dungar]

where does primary land on X or H

For probably, 99% of general purpose transformers: X designates the low voltage terminals and H the high voltage ones, per ANSI standards.

I have seen a just few step-up designs that don't follow those rules.

 

[LarryFine]

Where does primary land X or H

As Jim said, H-x's are the high-voltage terminals in almost every transformer.

So, 208v 3ph to X-1, X-2, and X-3, no neutral. Is this transformer meant as a step-up?

Delta-to-wye transformers are normally meant to have the delta as the primary.