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GEC question

ICE

ICE

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Joined
Jun 23, 2011
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California
There is a bonding fitting where the GEC and it's armor enters the enclosure. Then the armor continues. Should the armor stop at the bonding point? The armor is required to be bonded at every end so how about a foot from the end? Is that the same thing? I have read that the resistance of a gec with armor that is not bonded at the ends has been measured at 100 times greater than a gec with properly bonded armor.

I have posted this picture before in a thread related to the grounds but I couldn't find the thread.

DSCN0532.jpg
 
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The bushing is threaded to a fitting that is clamped to the FMC. Two questions, do you have an example of a bonding bushing that is listed for FMC and what is the bonding bushing in the picture listed for? Well now I'm up to three questions. Is this not legal because of the insulated insert?

I realize that the bonding jumper does not go to the bus bar and that is a violation but I am surprised to know that the bushing itself is not listed for FMC.

And here's a fourth question: How come I am just now finding this out?
 
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chris kennedy said:
If that bushing was installed on a FMC connector listed for grounding IMO that would be compliant.
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Help me understand this. Since you can't see the connector, how do you know it is wrong? The only thing that I can't see is the lock ring which has been replaced by the bonding bushing.

Here's another question: If the FMC connector is listed for grounding, why is a bonding bushing required at all? And let's not forget the original question.

Is this the connector you are talking about?

http://www.google.com/products/catalog?hl=en&q=flexible+metal+conduit+connectors&client=firefox-a&sqi=2&cid=9307976379919850505&ei=dPU_T-2nMYqKjgTP3qSPDQ&ved=0CBsQrhI
 
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ICE said:
And let's not forget the original question.
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IMO there are too many problems with the install to address the question. Would 110.3(B) require the FMC to be terminated at the connector? Sure. Is this installation a violation of 348.12(1), I believe so. The connector in your link is listed for dry location only as I believe all would be given FMC can't be used in wet locations.
 
chris kennedy said:
IMO there are too many problems with the install to address the question. Would 110.3(B) require the FMC to be terminated at the connector? Sure. Is this installation a violation of 348.12(1), I believe so. The connector in your link is listed for dry location only as I believe all would be given FMC can't be used in wet locations.
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You Honor, Permission to treat the witness as hostile please.

Isn't it the conductor that's in FMC that renders it not listed for a wet location? This is a bare #6 that carries no current. I have seen miles of FMC used to protect the GEC.
 
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ICE said:
You honor, Permission to treat the witness as hostile please.
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Permission granted.

Isn't it the conductor that's in FMC that renders it not listed for a wet location.
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Where does it say that???

348.12 Uses Not Permitted.FMC shall not be used in the following:

(1) In wet locations

(2) In hoistways, other than as permitted in 620.21(A)(1)

(3) In storage battery rooms

(4) In any hazardous (classified) location except as permitted by other articles in this Code

(5) Where exposed to materials having a deteriorating effect on the installed conductors, such as oil or gasoline

(6) Underground or embedded in poured concrete or aggregate

(7) Where subject to physical damage
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Also look at #7 above. Lets use a wiring method that shall not be used 'Where subject to physical damage' to protect the GEC from physical damage. Cool.

I have seen miles of FMC used to protect the GEC.
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Me too, seen tons of these installs on-line in other areas. That must make it OK.
 
chris kennedy said:
Permission granted.Where does it say that???

Also look at #7 above. Lets use a wiring method that shall not be used 'Where subject to physical damage' to protect the GEC from physical damage. Cool.

Me too, seen tons of these installs on-line in other areas. That must make it OK.
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Well that was a slam dunk. Indications are that the bushing is illegal because the FMC and connectors are illegal in their use. I am convinced. Then there is the reality of miles of it in use. Anyway, 110.3(B) gives me cause to stop the armor at the illegal bonding bushing.

My question wasn't answered but tests were probably not done with the armor a foot into the enclosure so there is no answer.

DSCN2505.jpg


DSCN0002-1.jpg


DSCN0531.jpg


IMG_2485.jpg
 
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jar546 said:
Wow, the work in these photos has reached new heights. You can write several novels with these photos. How do you find this stuff. Wow
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It is the stuff that I run into each day. I would be surprised to find out that my routine is all that much different than many of the other members. Shirley, the only difference is that I carry a camera and take the time to post pictures.

How could the electrician know enough about the trade to get this far and not understand the concept of removing paint? Or is it me that's wrong and these clamps work with paint? I find this a lot.

IMG_1891.jpg
 
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All of these ground rods reminds me of a story. The owner was driving a rod next to a residential panel. He hit a water pipe. And not just any water pipe. This pipe was huge and nobody that he contacted knew who owned the pipe. Well the panel was under an overhang and there was an eave vent directly above the rod. Water would have been shooting 30' skyward were it not for the overhang. The overhang directed the water through the eave vent. It ran for several hours and destroyed a nice family room.
 
ICE said:
How could the electrician know enough about the trade to get this far and not understand the concept of removing paint? Or is it me that's wrong and these clamps work with paint? I find this a lot.
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I have a guy thats been with me 14 months. I handed him a lug Thurs and told him to bond the wireway. (painted 3R type) He said, "OK, I'm gonna put a 250.12 on it." That kid is making me proud. :D
 
ice, it may be beneficial to obtain a copy of "Soares Book on Grounding and Bonding" it's like the bible that expalins in detail alot of the tough to understand requirrements in articel 250. i use one, it's invaluable. no comment on the photos, they art filtered by the city.
 
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