BX as a ground.

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mivey

Senior Member
No, that has never been my position.
OK. Just seemed that way. Hard to keep track sometimes.

If your intent is to have a grounded receptacle, then yes, the BX must be replaced because it's no longer recognized by the NEC as an EGC. Therefore rewiring is one option, or simply install a 2-wire receptacle. That has been my position on this from the very beginning.
Keep in mind that some don't really want a grounding receptacle, just a place for a third prong so they can plug stuff in.

Simply relying on the BX armor as an EGC is unacceptable because it's a code violation.
and more importantly, doesn't work well.

K&T is obviously an ungrounded system so there is no debate there. The great debate here is whether BX armor is a legitimate EGC or not.
Do you or do you not agree that it was at one time?
 

peter d

Senior Member
Location
New England
OK. Just seemed that way. Hard to keep track sometimes.

Keep in mind that some don't really want a grounding receptacle, just a place for a third prong so they can plug stuff in.

True enough, but aren't we here to endlessly debate the code? ;)

and more importantly, doesn't work well.

Do you or do you not agree that it was at one time?

I saw the posted code sections and I agree that it once was recognized by the NEC as an EGC. But I think it's also plain that the modern code has changed and has superseded those past editions of the code. This whole argument is pretty cut and dry to me and probably most everyone else, but for some reason it's been made needlessly complicated and convoluted. Putting the code aside, just a common sense evaluation of old BX should tell us that using old BX as an EGC is a bad idea for the reasons already stated (high impedance, unknown mechanical continuity, corrosion of the armor, etc.)
 

mivey

Senior Member
True enough, but aren't we here to endlessly debate the code? ;)
or most anything really. :p

I saw the posted code sections and I agree that it once was recognized by the NEC as an EGC. But I think it's also plain that the modern code has changed and has superseded those past editions of the code. This whole argument is pretty cut and dry to me and probably most everyone else, but for some reason it's been made needlessly complicated and convoluted. Putting the code aside, just a common sense evaluation of old BX should tell us that using old BX as an EGC is a bad idea for the reasons already stated (high impedance, unknown mechanical continuity, corrosion of the armor, etc.)
No doubt it is a bad idea, all things considered.

I guess that just leaves: When does the code supersede and force a change to a parent component?
 

wwhitney

Senior Member
Location
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Occupation
Retired
The OP was asking that and it seems that Wayne, Peter, and some others seemed to fall into that camp.
I hope post 282 clarifies my position.
Do you or do you not agree that it was at one time?
I haven't seen any evidence in this thread that unbonded BX armor was ever an NEC EGC for new construction. My understanding is that the code introduced the term "EGC" several years after BX cable standards were changed to require a bonding strip. Apparently earlier NECs used some other terminology, and the unbonded BX armor was required to be grounded. So the debate has been whether this old "grounding means" can be used now as an EGC.

Cheers, Wayne
 
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peter d

Senior Member
Location
New England
or most anything really. :p

No doubt it is a bad idea, all things considered.

I guess that just leaves: When does the code supersede and force a change to a parent component?

My best answer: whenever a modification or extension is made to an existing system. I suppose there is some gray area (like the #16 EGC in early editions of thermoplastic NM cable) and some cut and dry (extending K&T or ungrounded NM cable.)
 

mivey

Senior Member
I hope post 282 clarifies my position.

I haven't seen any evidence in this thread that unbonded BX armor was ever an NEC EGC for new construction. My understanding is that the code introduced the term "EGC" several years after BX cable standards were changed to require a bonding strip. Apparently earlier NECs used some other terminology, and the unbonded BX armor was required to be grounded. So the debate has been whether this old "grounding means" can be used now as an EGC.

Cheers, Wayne
Why do you think "grounding means" is different from an ECG? What exactly do you think they were grounding with the "grounding means"? Seems to me they were grounding the same thing. We have clarified the "ground" "grounded" "earthed" and have more work to do in that area but that does not change the conductor.
 

mivey

Senior Member
My best answer: whenever a modification or extension is made to an existing system. I suppose there is some gray area (like the #16 EGC in early editions of thermoplastic NM cable) and some cut and dry (extending K&T or ungrounded NM cable.)
How does changing from a two-hole receptacle with screw available for a grounding jumper wire with spade terminal to a three-hole receptacle with a ground hole modify the branch circuit? Granted neither one is a great ground but it is the ground system in place.
 

peter d

Senior Member
Location
New England
How does changing from a two-hole receptacle with screw available for a grounding jumper wire with spade terminal to a three-hole receptacle with a ground hole modify the branch circuit? Granted neither one is a great ground but it is the ground system in place.

It doesn't modify the branch circuit, but it's a modification to the system.

I don't know how other people do their jobs, but when I replace receptacles on old wiring, the first question I ask myself is "Do I have a proper EGC here?" That then leads to other decisions that need to be made depending on what is available or not for an EGC.
 

GoldDigger

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Location
Placerville, CA, USA
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Retired PV System Designer
Keep in mind that some don't really want a grounding receptacle, just a place for a third prong so they can plug stuff in.
Which is exactly why the code has a provision to put in a properly labelled GFCI protected three wire receptacle, which I also advocated early in the thread.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
How does changing from a two-hole receptacle with screw available for a grounding jumper wire with spade terminal to a three-hole receptacle with a ground hole modify the branch circuit?
The receptacle is part of the branch circuit, so you have definitely modified the branch circuit.

Cheers, Wayne
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
Why do you think "grounding means" is different from an ECG?
I don't, I think that in the current code it is a synonym for EGC, which by definition is one of the items listed in 250.118. So unbonded BX cable armor is not an EGC, and the NEC requires that a grounding type receptacle installed today have a grounding path that does not rely on unbonded BX cable armor.

Al, however, seems to think that "grounding means," which is nowhere defined in the NEC, and never used before 406.4(D)(1) outside of informational notes, can be perfectly construed to get the result he wants.

Cheers, Wayne
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
Al, however, seems to think that "grounding means," which is nowhere defined in the NEC, and never used before 406.4(D)(1) outside of informational notes, can be perfectly construed to get the result he wants.
Please Wayne, stop giving YOUR opinion of what YOU think I'm saying and desiring, and give me the courtesy of quoting my words.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
I do have to check that "conductive path(s) that provides a ground-fault current path and connects normally non-current-carrying metal parts of equipment together and to the system grounded conductor or to the grounding electrode conductor, or both," is electrically present at the existing outlet in front of me and at the service center from which it originates and that will satisfy 250.130(C), most likely 250.130(C)(1) or 250.130(C)(5).
Al, you are quoting the definition of EGC there. Once your code path hits the definition of EGC, you are directed to 250.118.

Cheers, Wayne
 

iwire

Moderator
Staff member
Location
Massachusetts
I took that to mean that in his area they have enough cases that the AHJ deals with it regularly so may have some unique insights as opposed to areas that are not as old and don't see as much of this stuff.

That is not a code discussion, that is the same as a popularity contest. Al says he wants a code discussion but keeps pointing to how they do it in his area.


They have figured out that BX was a code recognized grounding means. If you read Al's posts and links you should see that.

I have never in this thread stated that BX was not a grounding means in the past. What I have stated is that it stopped being a grounding means when the standards changed. That does not mean all BX must be ripped out. It means when I modify or extend from the circuit I do not have a grounding means.

Would I use routine branch-circuit BX today to clear a ground fault? No.

Why are you making ground faults?:p

Would I install a GFCI breaker and three-prong outlets? Yes.

Not I.

Was BX ever a code accepted grounding means? Yes.

I agree, it was. It is not today.


Still waiting to see Al answer an easy question, can he add to a BX circuit with modern NM and treat it like he has a section 250.118 EGC.

(Edit: Al if you read this is it possible you answer this question directly and not buried in a long post with seven different things going on?)
 
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al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
you where asked two direct, yes or no questions that I still have not seen you answer in a direct way.
Forgive me. I haven't intentionally not responded, rather, I suspect the questions might have been more nuanced than you think. Try again.
Still waiting to see Al answer an easy question, can he add to a BX circuit with modern NM and treat it like he has a section 250.118 EGC.
(Edit: Al if you read this is it possible you answer this question directly and not buried in a long post with seven different things going on?)
Asked and answered. Respectfully, a Branch Circuit extension is another thread. Post 320.

Substantiation:
So it is your position that the 406.4(D)(1) language makes the existing "grounding means" into an EGC? I strongly disagree, for the reasons outlined previously.
BTW, since you see the existing grounding means as an EGC, do you have any problem with extending that branch circuit to a new outlet, using a wiring method with an EGC listed under 250.118? If that is not allowed, how do you make the distinction?
Your error, as I see it, is to assume, before you get to 406.4(D)(1), is that there is no existing grounding means. But I have shown you the Code that establishes the armor of armored cable as (in the 1918 NEC) a ground conductor and that is passed on through time as the language of the Code evolves. The 406.4(D)(1) required grounding-type receptacle is connected to the grounding means as an EGC.
BTW, let's keep it simple and stay with receptacle replacement, the question as the OP asked.

The point of my question was to explore the consequences of your idea that the language in 406.4(D)(1) makes the old "grounding means" into an EGC. To quote you, "in for a penny, in for a pound." How far are you willing to take that idea? Can I extend the branch circuit and rely on that "EGC"? If not, what's the difference?
406.4(D)(1) instructs me to connect the EGC contacts of the grounding-type device to the grounding means. . . It does not make any statement about 250.118. Tail Chasing.
you still haven't answered my question of how far, code-wise, you are willing to take your idea that 406.4(D)(1) makes the "grounding means" into an EGC. Under that thinking, can one code-compliantly extend the branch circuit in conjunction with replacing the receptacle?
Asked and answered. Tail Chasing.
you have never actually said whether I could extend a branch circuit while doing a 406.4(D)(1) receptacle replacement. If not, why not? If so, doesn't that seem like a problem to you?
Branch circuit extension is NOT receptacle replacement. ASKED AND ANSWERED already. . . .
 
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