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Discussion Starter · #4 ·
First 240V ILine I've installed. 600A 240V 3 Phase Grounded B.

The one thing I didn't like about it was that it had a 3 Pole main, but used 2 Pole breakers...B Phase got landed on the "neutral bar".
 

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First 240V ILine I've installed. 600A 240V 3 Phase Grounded B.

The one thing I didn't like about it was that it had a 3 Pole main, but used 2 Pole breakers...B Phase got landed on the "neutral bar".
That is okely dokely and safe assuming B phase is the grounded conductor. But I bet you know that so I am confused.
 

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What the **** is a grounded phase?
I take that to mean a corner grounded Delta system. Something very rarely seen here in Canada.


Edit: Stop that BBQ.....you beat me to it. LOL
 

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Discussion Starter · #10 ·
That is okely dokely and safe assuming B phase is the grounded conductor. But I bet you know that so I am confused.
I was speaking of strictly appearance. The panel was ordered for this specific job, it would have been "cleaner" appearance wise to have a 2P main in there instead of a 3P with an unused lug. That's just my opinion.

Such as this...
(We are replacing that breaker, just used it as an example)
 

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Is that entire panelboard supported by just two floor mounted vertical standard size struts?

Seems like it would move around a lot. I would have expected double size strut or supports at the top.
 

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How does that work? We don't do that up here.

Not to mention, why would you ever do that?
I bet you do have that in some plcaes.

If you have a delta supply, (A, B, C, no N) you have only two choices. It can be run ungrounded and that has advantages in factories. It means the first ground fault will not trip a breaker or open a fuse. In a perfect world the in house guys find the ground fault and clear it before the next ground fault happens on an another phase. That would be a short.

On the other hand if you need or want a grounded system you have to choose a phase to bond and typically that is B.

Keep in mind this is when you have a new voltage system from a generator, transformer, inverter etc.
 

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Discussion Starter · #13 ·
Is that entire panelboard supported by just two floor mounted vertical standard size struts?

Seems like it would move around a lot. I would have expected double size strut or supports at the top.
Yeah, I'm not entirely happy with the support. It IS very solid, but half wished we did it a different way. There are unistrut feet mounted below the deck to the concrete floor and the vertical struts are mounted to the 225KVA Xfmr. The Xfmr is bolted down to the deck with (4) 1/2" lag bolts.
 

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I bet you do have that in some plcaes.

Yes Bob......you're right. We do still have some corner grounded Delta, however, I have seen very very few of them.

Over the last 25 yrs......I have worked in every province and territory in this country except Quebec, on some seriously old sites and buildings and large factories...........and I bet I could count the number of corner grounded Delta systems I've seen on ten fingers and probably have a few left.
 

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Discussion Starter · #16 ·
I think it is a 2 1/2" 90 degree sealtite connector. I prefer to use LB's, but this one was already there.
 

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Discussion Starter · #18 ·
Yes Bob......you're right. We do still have some corner grounded Delta, however, I have seen very very few of them.

Over the last 25 yrs......I have worked in every province and territory in this country except Quebec, on some seriously old sites and buildings and large factories...........and I bet I could count the number of corner grounded Delta systems I've seen on ten fingers and probably have a few left.
It's not real common here either, but some of the auxiliary equipment to these presses calls for it.
 

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jza said:
How does that work? We don't do that up here. Not to mention, why would you ever do that?
Notwithstanding what BBQ posted, down here the POCO decided what kind of 3 phase power a customer would get. Corner grounded delta lets the POCO get away with running only 2 phase conductors and a neutral to a location and then only two transformers at the drop. Back in the old days corner ground delta was used quite a bit here in rural Texas for oil wells, cotton gins and things like that out from the main distribution lines.
 

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Yes Bob......you're right. We do still have some corner grounded Delta, however, I have seen very very few of them.

Over the last 25 yrs......I have worked in every province and territory in this country except Quebec, on some seriously old sites and buildings and large factories...........and I bet I could count the number of corner grounded Delta systems I've seen on ten fingers and probably have a few left.
Pretty much the same here but I don't spend a lot of time in industrial where I think it is more common.

Wye is almost all I have ever had to work with.
 
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