Debate on over Flex as Grounding Conductor

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iwire said:
There is a difference to the NEC, if you only need it to flex during installation it can be an EGC. However if it needs to flex after the installation, say some wiring going to a door that has to open and close once in a while, in that case the NEC requires a wire ground inside the flex regardless of length.
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Which makes since because flexing over and over again could weaken or break the ground or flex in this case.
 
roger said:
It is allowed, 250.118(5) recognizes the FMC as an EGC itself when it meets the conditions of 250.118(5), which in turn meets the requirement of 517.13(A). When an insulated EGC is added into the FMC the requirement of 517.13(B) is met.

Roger
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Thats exactly my point. The key word here is after installation, not during installation. This is just flex from a panel to a j-box less than 6ft away. It was just easier to fish the flex down the wall to get to the panel. Dont know about others, but I really dont like mc or ac to the main panel. It may be legal, but I personally try to avoid it if I can, just like I feel that 3/4 should be minimum on home runs to a panel when branching out to other outlets. ;)

Like others said, the only time I can think of when you need flexibilty after installation is like for motors or opening doors or light fixtures hanging on chains from a ceiling etc..

It just pains me to hear of an inspector (like one here) that would not accept an installation based on an 'opinion' not code. People wonder why there is such a tension with some inspectors.
 
brother said:
Thats exactly my point. The key word here is after installation, not during installation. This is just flex from a panel to a j-box less than 6ft away. It was just easier to fish the flex down the wall to get to the panel. Dont know about others, but I really dont like mc or ac to the main panel. It may be legal, but I personally try to avoid it if I can, just like I feel that 3/4 should be minimum on home runs to a panel when branching out to other outlets. ;)

Like others said, the only time I can think of when you need flexibilty after installation is like for motors or opening doors or light fixtures hanging on chains from a ceiling etc..

It just pains me to hear of an inspector (like one here) that would not accept an installation based on an 'opinion' not code. People wonder why there is such a tension with some inspectors.
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Brother, I think you need to go back and read Augies replies again, his replies were based on flexibility being needed, if an installing electrician provided the same reason you did I'm sure he would look at it differently.

Roger
 
I'm pretty much in agreement with Roger on this one on both points, the flex should be approved and don't be so hard on Gus.

Does the connection "really" need flexibility or are you just using that as your argument? If the piece of equipment is just going to vibrate that's one thing, but if you are going to be moving it around, I'm not sure that flex is the best way to go.
 
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cowboyjwc said:
If the piece of equipment is just going to vibrate that's one thing, but if you are going to be moving it around, I'm not sure that flex is the best way to go.
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I was thinking the same thing, I was trying to picture something that would only once in a while. If it is going to be flexing all the time (beyond simple vibration) it seems a cord would be a better choice.
 
brother, For what it's worth, I really bend over backward not to enforce "my opinion" per se', and don't recall in 20+ years of inspecting in requiring anything be completed "my way", without supporting Code wording. Since the Code can not address every conceivable aspect, at times, all inspectors must interpret and this becomes "opinionated", but it's an "opinion" based on review, discussion, etc. That's why we are on the Forum.
My hesitancy to pass such an install (flexibility needed AFTER installation) actually was originally based on YOUR O.P. Since as you originally stated "there is a debate", apparently I'm not the only one to question the Code on this matter.
My "decision" is/was based to some degree on the narrative in the Handbook, which I'm sure, although not Code, influences many of us. Secondly it's based on being in the field for 50 years and seeing a lot of broken flex.
I appreciate the OP and still am hopeful someone can describe an approved method that could be used without using flex.
 
augie47 said:
brother, For what it's worth, I really bend over backward not to enforce "my opinion" per se', and don't recall in 20+ years of inspecting in requiring anything be completed "my way", without supporting Code wording. Since the Code can not address every conceivable aspect, at times, all inspectors must interpret and this becomes "opinionated", but it's an "opinion" based on review, discussion, etc. That's why we are on the Forum.
My hesitancy to pass such an install (flexibility needed AFTER installation) actually was originally based on YOUR O.P. Since as you originally stated "there is a debate", apparently I'm not the only one to question the Code on this matter.
My "decision" is/was based to some degree on the narrative in the Handbook, which I'm sure, although not Code, influences many of us. Secondly it's based on being in the field for 50 years and seeing a lot of broken flex.
I appreciate the OP and still am hopeful someone can describe an approved method that could be used without using flex.
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Or just add the grounding conductor and be done. I do not envy inspectors its a lot of learning and interperting they have to do with rules that arent always clear.
 
jwjrw said:
Or just add the grounding conductor and be done. I do not envy inspectors its a lot of learning and interperting they have to do with rules that arent always clear.
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That does not change the fact that the metallic raceway must be recognized as an EGC.

Roger
 
roger said:
That does not change the fact that the metallic raceway must be recognized as an EGC.

Roger
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I thought if it had a ground ran with it then the flex wouldnt have to be an ecg it would be for protection from damage only.
 
A few people have asked me for an example of not requiring flexibility after installation. The one that I always use is a 6' fixture whip. Once the fixture is in place the flexibility of the FMC is no longer needed. the flexibility just helped the installer when he put in the fixture. :)
 
cowboyjwc said:
I'm pretty much in agreement with Roger on this one on both points, the flex should be approved and don't be so hard on Gus.

Does the connection "really" need flexibility or are you just using that as your argument? If the piece of equipment is just going to vibrate that's one thing, but if you are going to be moving it around, I'm not sure that flex is the best way to go.
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There will be no moving around, or vibration after the install. Like I said before, it was just easier to fish the flex down the wall to the panel and then connect the other end to the j-box (that is fixed and not moving). Maybe there was a 'misunderstanding' when I said the flexibility was necessary in my o.p. , but that was for fishing , not AFTER the install was done.

So the flex is an egc under those conditions.
 
Awwww, well in that case I would say that the original inspector or whomever made the call was right. You're not meeting all of the requirements of 250.118. I also would have thought that it would be easier to fish a piece of hospital grade cable down the wall.

I decided to expand on this answer. We allow flex here in medical (we don't do hospitals) simply because we do accept the green tag, but that may not be the case where you are.
 
cowboyjwc said:
Awwww, well in that case I would say that the original inspector or whomever made the call was right. You're not meeting all of the requirements of 250.118. I also would have thought that it would be easier to fish a piece of hospital grade cable down the wall.

I decided to expand on this answer. We allow flex here in medical (we don't do hospitals) simply because we do accept the green tag, but that may not be the case where you are.
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You don't allow Hospital Grade AC cable, or MC-CAP ?
 
cowboyjwc said:
Awwww, well in that case I would say that the original inspector or whomever made the call was right. You're not meeting all of the requirements of 250.118. I also would have thought that it would be easier to fish a piece of hospital grade cable down the wall.
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John, what requirements are not being met? The flex is no longer than 6' with fittings listed for grounding and being protected by no more than a 20 amp OCPD is basically all that is needed, IOW's all of 250.118(5) is satisfied.

Roger
 
roger said:
John, what requirements are not being met? The flex is no longer than 6' with fittings listed for grounding and being protected by no more than a 20 amp OCPD is basically all that is needed, IOW's all of 250.118(5) is satisfied.

Roger
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d. Where used to connect equipment where flexibility is necessary after installation.
 
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