On 1/4/22 8:06 AM, Jonathan Chapman via cctalk wrote:
Yes, that's open delta. There are one or two small commercial buildings
here in town that still have open high leg delta service -- that's
240V delta, and one of the 240V transformers is center-tapped to give
120/240 split phase for small loads.
I'm having trouble reconciling that with my current mental understanding.
First I have to bring up line vs phase. My understanding is that the
line is the actual wire, and a phase is what runs over the two lines.
I can see how you might use two lines combined with a "corner ground"
for as the third line for a delta configuration. Thus you have three
three distinct line parings ~> phases. L1+G, L1+L2, L2+G.
If that is not what's being discussed in this case, then I have no idea
what it is.
My guess is, aside from saving on wire, insulators, etc. (not
significant in town), the real savings is on disconnects and the
extra transformer.
I apparently need to do more reading. I'm not seeing how corner ground
delta will save a transformer. Or I'm completely misunderstanding
things. -- Time to research "open delta".
--
Grant. . . .
unix || die
