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Feeder with no EGC

5131 Views 30 Replies 15 Participants Last post by  RIVETER
I am bidding on a couple of panel changes. - The first panel is fed from a 200A disconnect; the feeders are run in metal conduit with no equipment ground conductor. It seems to me that there might be an exception that allows this in an existing installation. (I want to leave the feeders alone in possible. It is a long run and I am trying to keep costs down... Maybe I should just plan on replacing them, but anyway:whistling2:) Any ideas here? I think the metal conduit is the EGC but not completely sure that is okay... something new or unfamiliar every day!
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I am bidding on a couple of panel changes. - The first panel is fed from a 200A disconnect; the feeders are run in metal conduit with no equipment ground conductor. It seems to me that there might be an exception that allows this in an existing installation. (I want to leave the feeders alone in possible. It is a long run and I am trying to keep costs down... Maybe I should just plan on replacing them, but anyway:whistling2:) Any ideas here? I think the metal conduit is the EGC but not completely sure that is okay... something new or unfamiliar every day!
Have you ever read 250.118?

Roger
 

· IBEW L.U. 1852
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Its not my preferred way of doing things if the metal conduit is emt with set screw couplings and connectors although its allowed. We've all seen set screw fittings that are loose or have come open.

I have zero worries about it when its threaded rigid conduit however.

That rigid conduit would surely carry more fault current than a #6 wire in the case of a serious fault:laughing:
 

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There's a study called the "Georgia Tech Model" that seems to indicate that properly installed steel conduit is a superior EGC path over a copper conductor installed with the other circuit conductors.
 

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Its not my preferred way of doing things if the metal conduit is emt with set screw couplings and connectors although its allowed. We've all seen set screw fittings that are loose or have come open.

I have zero worries about it when its threaded rigid conduit however.

That rigid conduit would surely carry more fault current than a #6 wire in the case of a serious fault:laughing:
I have seen a lot more loose EMT compression couplings and connectors than I have set screw ones.

I have seen more than one rigid conduit run where the couplings were not made up tight and a fault blew holes in the threads at a number of couplings in the run.

I have also seen a lot of green wires that were not properly terminated.

A poor installation can be made no matter what the product is.
 

· IBEW L.U. 1852
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I have seen a lot more loose EMT compression couplings and connectors than I have set screw ones.

I have seen more than one rigid conduit run where the couplings were not made up tight and a fault blew holes in the threads at a number of couplings in the run.

I have also seen a lot of green wires that were not properly terminated.

A poor installation can be made no matter what the product is.
All so true don......although personally......I have seen more set screw stuff loose. I guess its like you said.....a hack install is a hack install.:thumbsup:
 

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I am bidding on a couple of panel changes. - The first panel is fed from a 200A disconnect; the feeders are run in metal conduit with no equipment ground conductor. It seems to me that there might be an exception that allows this in an existing installation. (I want to leave the feeders alone in possible. It is a long run and I am trying to keep costs down... Maybe I should just plan on replacing them, but anyway:whistling2:) Any ideas here? I think the metal conduit is the EGC but not completely sure that is okay... something new or unfamiliar every day!
If the portion of the conduit system seems to be installed correctly it probably is okay to be the EGC. Measure from point A to B to C and read the resistance.
 

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Discussion Starter · #13 ·
where is the service grounded? from the panel, or the disconnect?
Honestly, I'm not sure. When I was there looking at the whole thing I let the customer know I didn't want to take it apart or mess with it at that point. I was not charging her for the estimate. On a free estimate I am really hesitant to take even the covers off some of that old service equipment... you know that stuff can just fall apart on you and then you got something you have to deal with and nobody has signed or agreed to pay you anything. It was in a marshy area too.... I don't know who decided to put the service equipment right next to a wetland conservation area, but whatever.
 

· corn-fused
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imo in good contact with the earth in wet location, such as not in the desert where the water table is 30' or in many parts of the midwest where you cant go more than 3-4' without hitting rock, and im sure some others will fill in the voids. im getting tired, gotta get up early .
 

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Well... if it makes any difference to this thread, today I swapped out a panel, and replaced a three conductor really old style cloth braided ser cable panel feeder. All three conductors were insulated, red, black, blue, blue being used for the neutral. The original installer ran it for a single phase sub panel feed, and then ran an independent #8 bare copper to the cold water at the water heater. I have seen it enough times to believe it was an accepted practice here, probably in the nineteen sixties.
 
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