Is a "Closed Delta" different than a "Delta High-Leg"?
Neither high-leg delta nor a corner-grounded delta is a subset of a closed delta configuration as both configurations can be supplied by an open-delta transformer bank.High leg delta, corner-grounded delta, and standard delta, are all subsets of "closed delta". Meaning that all three transformer coils are connected in a closed loop among the phases.
The opposite is an open delta, which only has two transformer coils, such as AB and BC, but no CA.
Neither high-leg delta nor a corner-grounded delta is a subset of a closed delta configuration as both configurations can be supplied by an open-delta transformer bank.
A little more follow up on what Smart $ said.Is a "Closed Delta" different than a "Delta High-Leg"?
No. Closed delta or open delta is determined by the number of transformers, not the voltage level of the secondary.Yes. .....
Or one three phase transformer with the windings in a delta configuration perhaps?No. Closed delta or open delta is determined by the number of transformers, not the voltage level of the secondary.
Or one three phase transformer with the windings in a delta configuration perhaps?
No. Closed delta or open delta is determined by the number of transformers, not the voltage level of the secondary.
I did not realize that.:?
My "yes" was to the OP's question:
You can have a high leg on both an open and a closed delta. Do we agree?"Is a "Closed Delta" different than a "Delta High-Leg"?
Using different voltages in each example threw me off.The rest of my comment backs up your correction about # of xfmrs to make each.
I did not realize that.
You can have a high leg on both an open and a closed delta. Do we agree?
Using different voltages in each example threw me off.
Agreed, tho I dont think I've ever seen a closed high leg delta service. Two pot high leg set-ups are much more common, yes?
My background is industrial. Pole mounted isn't something I had to deal with. Here or in the States.Perhaps, but within the context of here in the States, you are only going to see delta power derived from pole mounted transformers. There may be some exceptions, but they are rare.
True for residential other than multi-family. Both industrial and apartment complexes out West may have pad mount transformers and all underground power service.Perhaps, but within the context of here in the States, you are only going to see delta power derived from pole mounted transformers. There may be some exceptions, but they are rare.
You guys probably arrange transformres different than how we arrange our transformers. You have three 50 hurts 240 tranformres without centre taps to get 415Y/240 which is not far from how we get commercial power using three 60 Hz 277 transformers for 480Y/277.My background is industrial. Pole mounted isn't something I had to deal with. Here or in the States.
A lot of full delta systems here - mostly 240 volt systems. If you are supplying a lot of 240 volt loads and limited 120 volt loads why go with a 208 volt wye system?I should have quoted the OP first to avoid confusion.
Agreed, tho I dont think I've ever seen a closed high leg delta service. Two pot high leg set-ups are much more common, yes?
Seen two or even three single phase padmounts connected to make a three phase bank before. Most of them were older and they would not likely use three anymore these days but rather a single core three phase unit, but I have seen more recently a new two unit open delta, but that has even been 10-15 years ago.True for residential other than multi-family. Both industrial and apartment complexes out West may have pad mount transformers and all underground power service.
You are not likely to see an open delta with pad mount. Those would either be complete three phase or single phase with one transformer.
I don't believe it is common at all to see a delta secondary supplying the end user over there.Closed would be the normal delta.
Open delta looks like this.
http://forums.mikeholt.com/showthread.php?t=155814&p=1507707#post1507707
Closed / open should be self explanatory.
You'll have the same voltages. Open delta often built with two different sized transformers and it is used to provide three phase service from a pole that primarily consists of single phase loads. The second and usually smaller transformer is used exclusively for three phase loads, such as irrigation pump or shop equipment.
You guys probably arrange transformres different than how we arrange our transformers. You have three 50 hurts 240 tranformres without centre taps to get 415Y/240 which is not far from how we get commercial power using three 60 Hz 277 transformers for 480Y/277.
Homes usually get 120/240 with a center tap transformer.
Same here although I can take you to a good number of corner grounded and one ungrounded around here.Gotta be a regional thing. There are a bunch of delta systems where I live, most are closed, but I can take you to an open delta quite easily. Most are 240V, most are high leg. Corner grounds are very rare and ungrounded is non-existent.