An open delta is two transformers used to supply three phases:
In an ordinary delta, you have three single phase transformers (or one 3-phase) connected phase - to -phase. Simply remove one of the single phase transformers to create an open delta.
This means you have a limited capacity over the phase which doesn't have a transformer, but it works.
See Scotts drawings in the Reference area: http://electrical-contractor.net/ubb/Forum15/HTML/000054.html
You can create something similar to V-phase by grounding one phase conductor. This is called a corner grounded delta and is sometimes used.
Would it be possible to distribute 3-phase with only two wires and two single phase transformers (at the receiving end)? If so, how?
[This message has been edited by C-H (edited 07-05-2004).]