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Equipment ground to sub panel?


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Is it OK for the EG feeder to be split up on the ground bar at the main panel?

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Absolutely not allowed !

The reason is; that stranded conductor is rated ( and tested/approved) to carry a certain amount of amperage based on the size of all those individual strands combined into 1 stranded conductor. Now that they are split up that section of the conductor is no longer rated to that amount of amperage.

Lets say there is a fault condition that puts amperage on that conductor. there is a possibility of overloading the sections at the terminal bar. Those split up sections could possibly overload to the point of melting! Rare ,but possible.

IMHO - ANY inspector who does not call this out should hang it up and go work as a Wal-Mart Greeter or McDonalds !

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Jim, which side of the doorway do you want to work?

Hey, I never said I wouldn't report it. With things like this, if it's the only electrical note, I advise folks to get it fixed the next time an electrician is present for other repairs. If there are other electrical repairs needed, I just lump it in with them. I generally report things when they're wrong, even if they're likely to be benign.

Sorry if my answer was misleading. I didn't think you were asking for reporting advice.

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I understand that this isn't allowed. But I'd like to better understand why it's not allowed. The solution is to install a single terminal lug, right? So that would put all of the current at just one section of the terminal bar. So clearly the danger isn't that the terminal bar might be overloaded.

Electricity flows primarily along the surface of the wire, right? So I don't see the physical problem with load carrying capacity being reduced.

Maybe the problem is that splitting up the strands can cause some sort of arc among the different strands. Does that sound right?

Anybody know for sure?

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I understand that this isn't allowed. But I'd like to better understand why it's not allowed. The solution is to install a single terminal lug, right? So that would put all of the current at just one section of the terminal bar. So clearly the danger isn't that the terminal bar might be overloaded.

Electricity flows primarily along the surface of the wire, right? So I don't see the physical problem with load carrying capacity being reduced.

Maybe the problem is that splitting up the strands can cause some sort of arc among the different strands. Does that sound right?

Anybody know for sure?

Like Jim opined, few, if any, consequences will result. It's mostly about being consistent with what the manufacturer intended, avoiding practices that haven't been evaluated and keeping the variables to a minimum.

Marc

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I understand that this isn't allowed. But I'd like to better understand why it's not allowed. The solution is to install a single terminal lug, right? So that would put all of the current at just one section of the terminal bar. So clearly the danger isn't that the terminal bar might be overloaded.

Electricity flows primarily along the surface of the wire, right? So I don't see the physical problem with load carrying capacity being reduced.

Maybe the problem is that splitting up the strands can cause some sort of arc among the different strands. Does that sound right?

Anybody know for sure?

Honestly, the reason its wrong is because the NEC and the testing standard say so. The reason to report it is so that you don't look like a dope when the next guy reports it.

If none of the strands are omitted, and the connections are secure, the likelihood of it every causing an electrical problem is very close to zero.

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Honestly, the reason its wrong is because the NEC and the testing standard say so. The reason to report it is so that you don't look like a dope when the next guy reports it.

If none of the strands are omitted, and the connections are secure, the likelihood of it every causing an electrical problem is very close to zero.

Well I suppose that saying it isn't allowed because nobody has ever proved that it works is not completely unreasonable.

Still, I have to believe that somewhere, somehow, somebody on some code-making committee has a theory as to what might go wrong.

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. . . Still, I have to believe that somewhere, somehow, somebody on some code-making committee has a theory as to what might go wrong.

I doubt it. It's more like, "We know it works right this way. We don't know whether or not it works right that way."

No one has written a standard that covers separating the strands of a wire and placing them under two lugs.

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The reason to report it is so that you don't look like a dope when the next guy reports it.

There's a fair amount of that in this job nowadays.

I see this done by Local 134 guys and no one squawks. There's no hazard other than the next guy saying it should be fixed.

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That's easiest.

In my own life, I own a fair amount of equipment with picayune anomalies that I ceased caring about years ago. I'll love seeing the home inspection report when I sell my place someday.

Yeah, that report is gonna say more about the inspector than the house.

The judge gets judged.

Marc

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It's definitely not allowed, and personally I don't care why. Code is code.

Thing is, that will fit in one hole! I am amazed at how many times I see this when it is completely unnecessary.

That looks to me like #2SER, which makes the EGC #4. Pretty much every modern ground and neutral bar WILL accept up to #4.

#4 aluminum stranded?

Marc

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