what type of service is this?

[480sparky]

man I can't understand how this would work if there is no voltage present on this leg.

Try going here. They may have something that 'splains it better.

 

[augie47]

there is voltage present....when you measure to the other two lesg you see it...
just like ypu see voltage when you measure from hot to neutral on a 240/120 circuit... when you measure neutral (grounded) to ground you see no voltage there,,but the retun path is still there...it's still a part of the circuit... same here..the c phase is still part of the circuit..it happens to be grounded.

 

[iwire]

man I can't understand how this would work if there is no voltage present on this leg.

There is 'voltage present' on that conductor relative to the two other phases just not to ground.

 

[augie47]

I don't have a corner delta graphic... this is as close as I coud find...
Ignore "N" in this case, as you don't have "N", and ground one phase.

 

[iwire]

This may help, it has B phase grounded.

From here New: 3 Ph. 3 Wire Corner Grounded Delta dgs.

 

[steelersman]

I appreciate everyone's feedback. Thanks for the input. I think I'm starting to understand it a little bit now. And this will probably be the last (and first) time I see this type of service.

 

[jim dungar]

I appreciate everyone's feedback. Thanks for the input. I think I'm starting to understand it a little bit now. And this will probably be the last (and first) time I see this type of service.

It seems, on this forum, we discuss 240V grounded-phase, 240V ungrounded, and 240/120 4 wire at least every couple of weeks. While delta systems are not common, I think they are not as rare as people make them out to be.