BX as a ground.

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al hildenbrand

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Minnesota
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Electrical Contractor, Electrical Consultant, Electrical Engineer
BTW, it occurs to me my "good luck in the real world" could be read as sarcastic. I was just responding politely to your meat space comment and didn't feel like using that term.

Cheers, Wayne
:thumbsup: Thank you. In all things, charity. I'm glad to hear that.
("meat space" is somewhat of a cyberpunk sci-fi term that I like for it's jarring clarity. "real" might seem a snub that this thread is not "real" and a snub is not my intention, nor experience.)
 

wwhitney

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Location
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I'm not missing your point. A new devices has a two conductor count, the old existing device before removal, was one conductor.
Ah, I'm not familiar with the whole history of 314.16, but I do recall such a change. That particular change muddies the waters a little, surely there were other changes. What about them? Am I required to apply such changes in 314.16 to the existing box when changing a receptacle, or not? If yes, how is that different than 250.118?

without the actual Code language instruction to reverse the inspected and approved status of existing Branch Circuit method
If such language is required to avoid grandfathering, why does the code include explicit grandfathers such as the exceptions to 250.140 and 250.32(B)(1)?

Answer: there is no grandfathering without such explicit language. The burden is on you to find grandfathering language, not on me to find "anti-grandfathering" language.

Also, I don't think you've ever responded to my post 159.

Cheers, Wayne
 

wwhitney

Senior Member
Location
Berkeley, CA
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406.4(D)(1) instructs me to connect the EGC contacts of the grounding-type device to the grounding means
In fact, it does not. It tells you "grounding-type receptacles . . . shall be connected to the equipment grounding conductor". Which directly leads to the definition of EGC and thence to 250.118. I really don't get how you think that the use of the words "grounding means" earlier in 406.4(D)(1) suddenly makes that "grounding means" into an EGC, contrary to the definition of EGC and 250.118.

Wayne, that is a safety argument, based on knowledge from OUTSIDE the text of the NEC.
My speculation as to your motives is a safety argument, but 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?

Cheers, Wayne
 

iwire

Moderator
Staff member
Location
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These are from this thread.

Al I have no idea how you think my post to Romex jockey supports your position.

My point to RJ is you can't use today's 250.118 to justify decades old BX

I agree it looks like you have a few supporters but in my view wwhitney has countered all your points even though you seem to refuse to answer a couple of his questions.
 

jim dungar

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PE (Retired) - Power Systems
...there is no grandfathering without such explicit language. The burden is on you to find grandfathering language, not on me to find "anti-grandfathering" language.

The State of Wisconsin code went out of its way to include language like:
(3) EXISTING INSTALLATIONS. Existing electrical installations shall conform to the electrical code that applied when the installations were installed.
(4) REPAIRS. Repairs to electrical installations shall conform to the electrical code that applied when the installations were installed.

With the over caveat: "An existing electrical installation may be required to be brought into compliance with the current code’s requirements by the department and within the time period determined by the department when a hazard to life, health or property exists or is created by the installation.
 

GerryB

Senior Member
The State of Wisconsin code went out of its way to include language like:
(3) EXISTING INSTALLATIONS. Existing electrical installations shall conform to the electrical code that applied when the installations were installed.
(4) REPAIRS. Repairs to electrical installations shall conform to the electrical code that applied when the installations were installed.

With the over caveat: "An existing electrical installation may be required to be brought into compliance with the current code’s requirements by the department and within the time period determined by the department when a hazard to life, health or property exists or is created by the installation.
I think this answers the practical experience I have had in many towns in my state. No inspector I have had dealings with ever brought it up as a concern.
One job where a property owner (multifamiy) did his own work and got shut down and we came in to fix it there was a lot of old bx in the basement, some that had rust and corrosion. The inspector had us change those rusty runs only.
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
in my view wwhitney has countered all your points even though you seem to refuse to answer a couple of his questions.

OK, please consider the following:

BX cable without a bonding strip is not type AC cable, per 320.2 and 320.100:
Originally Posted by 2011 NEC 320.2 Definition. Armored Cable, Type AC. A fabricated assembly of insulated conductors in a flexible interlocked metallic armor. See 320.100.

320.100 Construction. Type AC cable shall have an armor of flexible metal tape and shall have an internal bonding strip of copper or aluminum in intimate contact with the armor for its entire length


320.2 incorporates the requirements of 320.100 into the definition of type AC cable. So no bonding strip means it's not type AC cable.

Given that, is BX cable without a bonding strip a recognized Chapter 3 wiring method? If not, then when dealing with it replacement is only the option.
As you have agreed in post #254, the existing Branch Circuit conductors are not modified. That is, the EXISTING Branch Circuit is EXISTING, and, when the Existing Branch Circuit is a system of Armored Cable type-BX installed to the Code in effect during its original construction as a grounding means (as described in the language of THAT Code in effect during it original construction), then I see nothing in 320.2 or 320.100 that says installed and approved NON-AC-Type Armored Cable must be must conform to the Armored Cable type AC standards. Tail Chasing.
Ah, I'm not familiar with the whole history of 314.16, but I do recall such a change. That particular change muddies the waters a little, surely there were other changes. What about them? Am I required to apply such changes in 314.16 to the existing box when changing a receptacle, or not? If yes, how is that different than 250.118?
Asked and already answered. The box is existing with its existing volume. The device in a DEVICE REPLACEMENT is a new device and it has a conductor count of two from Today's NEC because it is a NEW replacement device. I again ask that, to keep this discussion to the OP topic, that we let the EXISTING box have enough cubic inches to accommodate the new cubic inch requirement of the NEW replacement device.

How is this different than 250.118? The grounding means of the EXISTING Armored Cable type BX Branch Circuit is EXISTING. No new Equipment Grounding Conductor is being installed in a receptacle replacement.
The NEC is a NEW construction standard.

If such language is required to avoid grandfathering, why does the code include explicit grandfathers such as the exceptions to 250.140 and 250.32(B)(1)?

Answer: there is no grandfathering without such explicit language. The burden is on you to find grandfathering language, not on me to find "anti-grandfathering" language.[/QUOTE]Wayne I did. And I've repeatedly posted it for you, specifically, and in other posts than yours. Tail Chasing.

"Code Silence" is simple, neither pro nor con.


Al I have no idea how you think my post to Romex jockey supports your position.

My point to RJ is you can't use today's 250.118 to justify decades old BX
My apologies for misunderstanding the quote of you that I posted. I reserve the right to return to this . . . I'll take you at you word for the moment without unpacking my error.

I agree it looks like you have a few supporters . . .

And, as I count, I have a few detractors. This is not a popularity contest. This is a Code discussion.
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
In fact, it does not. It tells you "grounding-type receptacles . . . shall be connected to the equipment grounding conductor". Which directly leads to the definition of EGC and thence to 250.118. I really don't get how you think that the use of the words "grounding means" earlier in 406.4(D)(1) suddenly makes that "grounding means" into an EGC, contrary to the definition of EGC and 250.118.
Asked and answered. Tail Chasing.


My speculation as to your motives is a safety argument, but 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.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
Hi Al,

I'm going to agree with you that we seem to have a fundamental disagreement on the following points, which I will state from your point of view:

1) That silence in the code implies grandfathering. [That is the only reference of yours I found as far as grandfathering language.]
2) That 250.118 may be ignored unless specifically referenced by some other code passage.
3) That the use of the phrase "grounding means" in 406.4(D)(1) means something broader than EGC, and modifies later use of the phrase EGC.
4) That it is valid to choose 250.130(C) in 406.4(D)(1) when replacing a grounding receptacle with a grounding receptacle.

So I agree let's avoid the "tail chasing" on those issues (your repetition of which is annoying, but I expect that is intentional).

I am still interested in exploring the consequences of (2) and (3) above, and I have posed a couple questions about them that you have dismissed or not addressed head on. Obviously these questions are partially hypothetical, but that is the point, to show that (2) and (3) lead to ridiculous or inconsistent consequences. So

A) For (2), on 314.16, why does it apply to receptacle replacement when 250.118 does not? In particular, I'm interested in the case where the original installation included an allowance of 2 for the receptacle, but some other change in 314.16 pushed the required box volume above that present. Would you have to change out the box in that case when doing a receptacle replacement?

B) For (3), contrary to your last statement on the matter, 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?

Cheers, Wayne
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
The State of Wisconsin code went out of its way to include language like:
(3) EXISTING INSTALLATIONS. Existing electrical installations shall conform to the electrical code that applied when the installations were installed.
(4) REPAIRS. Repairs to electrical installations shall conform to the electrical code that applied when the installations were installed.
Which suggests that the State of Wisconsin agrees that absent such language, there is no general grandfathering in the NEC.

With the over caveat: "An existing electrical installation may be required to be brought into compliance with the current code’s requirements by the department and within the time period determined by the department when a hazard to life, health or property exists or is created by the installation.
What do people think of the following proposition: existing unbonded BX cable armor used as a grounding means is an "actual hazard to life, health or property," as its high impedance presents an unacceptable risk that during a ground fault the OCPD will not trip. This could easily lead either to a shock hazard (hot frame of equipment) or a fire (from excessive heating of the armor).

Cheers, Wayne
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
Hi Al,

I'm going to agree with you that we seem to have a fundamental disagreement on the following points, which I will state from your point of view:
These are not my words. I don't accept them as coming from my keyboard. These are your opinions about my words, in your own words.

1) That silence in the code implies grandfathering. [That is the only reference of yours I found as far as grandfathering language.]
No.
The Code is silent. What did I just post above about Code silence. Your opinion about my words twists it into something I did not write.
2) That 250.118 may be ignored unless specifically referenced by some other code passage.
No.
Asked and answered in all that I have written about 406.4(D)(1)
3) That the use of the phrase "grounding means" in 406.4(D)(1) means something broader than EGC, and modifies later use of the phrase EGC.
No.
406.4(D)(1), in stating "Where a grounding means EXISTS". . . is deliberately crafting a phase to encompass EXISTING Branch Circuits installed to the Code in effect at the time of their installation. This is a repeat. ASK and ANSWERED. Tail chasing.
4) That it is valid to choose 250.130(C) in 406.4(D)(1) when replacing a grounding receptacle with a grounding receptacle.
Yes.

So I agree let's avoid the "tail chasing" on those issues (your repetition of which is annoying, but I expect that is intentional).
Sorry. Until you can quote me, or paraphrase me as I mean what is quotable, I will continue to call out the tail chasing.

I am still interested in exploring the consequences of (2) and (3) above, and I have posed a couple questions about them that you have dismissed or not addressed head on. Obviously these questions are partially hypothetical, but that is the point, to show that (2) and (3) lead to ridiculous or inconsistent consequences.
In your opinion. I have my opinion.

A) For (2), on 314.16, why does it apply to receptacle replacement when 250.118 does not?
Asked and answered. Tail chasing.

In particular, I'm interested in the case where the original installation included an allowance of 2 for the receptacle, but some other change in 314.16 pushed the required box volume above that present. Would you have to change out the box in that case when doing a receptacle replacement?
Again, to keep this simple and on target to the OP scenario, let there be enough cubic inches in the existing box.

Again. Asked and answered. Tail chasing.

B) For (3), contrary to your last statement on the matter, 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. . . .
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
One thing that bothers me about this whole thing. Forget about grounding receptacles for the moment. Ground faults within the boxes and wiring are common. Don't you think that back when BX came into use they were just as smart as we are now and if the OCP (fuse) wouldn't be able to protect they would have figured it out? I think it worked just fine when it was new. So why the problem now? Is oxidation and corrosion over the years the cause? And what about that aluminum bonding strip under steel armor today? Two dissimilar metals.

-Hal
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
I'm going to agree with you that we seem to have a fundamental disagreement on the following points, which I will state from your point of view:
OK, I seem to have failed on 3 out of 4 of these points, good to know, that was part of the idea. So let's see if we can improve things:

1) That silence in the code implies grandfathering. [That is the only reference of yours I found as far as grandfathering language.]
OK, it's not the silence that implies the grandfathering, the silence is neutral. So where's the explicit grandfathering language? A "path through 406.4(D)(1)" is not explicit grandfathering language. The single use of the phrase "grounding means" in 406.4(D)(1) is not explicit grandfathering language.

BTW, most of the time when you say "asked and answered" I have no idea what part of what post you feel is a direct response to my question, as this thread is long, and what looks to you like a direct answer to my question looks to me like an indirect answer or avoiding the question.

2) That 250.118 may be ignored unless specifically referenced by some other code passage.

No. Asked and answered in all that I have written about 406.4(D)(1)
My understanding of all of that is (a) you read 406.4(D)(1) in a way that never leads directly to 250.118 and (b) since 406.4(D)(1) doesn't lead you to 250.118, it doesn't apply. How is that different from what I wrote? How about if I amend that to "For an existing installations, 250.118 may be ignored unless specifically referenced by some other code passage."? That kind of puts it back with the point (1) about grandfathering, so maybe this not a separate point.

3) That the use of the phrase "grounding means" in 406.4(D)(1) means something broader than EGC, and modifies later use of the phrase EGC.

No.
406.4(D)(1), in stating "Where a grounding means EXISTS". . . is deliberately crafting a phase to encompass EXISTING Branch Circuits installed to the Code in effect at the time of their installation.
OK, I get that is your idea. Can we agree that "EGC" normally means what its article 100 definition says, and that since the definition references 250.118, it only means those things listed in 250.118? Hence my statement that your position is "That the use of the phrase "grounding means" in 406.4(D)(1) means something broader than EGC." Is that part incorrect?

The fact that you go on to say that the phrase "grounding means" in 406.4(D)(1) is what the later term "EGC" in 406.4(D)(1) refers to, rather than its usual definition, is why I wrote "and modifies later use of the phrase EGC." Is that part incorrect?

Or are you saying that the use of the phrase "grounding means" has the effect that for the purposes of receptacle replacement only, the existing "grounding means" may be treated as an EGC? If so, that's a pretty specific and powerful effect for an undefined term used nowhere previously in the NEC. I really can't buy that, but we can agree to disagree.

I really do want to get this right, so I understand your position, it is possible I'm misunderstanding.

BTW, is there any way to fairly easily see the entire history of 406.4(D)(1) through the ages?

Cheers, Wayne
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
Forget about grounding receptacles for the moment.

Hi Hal,
Yes, there are the safety studies, field reports, anecdotal accounts, engineering analysis and more that are surrounding Armored Cable, either AC or BX. But that, respectfully, is another thread.

This thread is at 275+ posts on the NEC with respect to receptacle replacement in an existing Outlet, per the OP, if that's OK?
 

iwire

Moderator
Staff member
Location
Massachusetts
One thing that bothers me about this whole thing. Forget about grounding receptacles for the moment. Ground faults within the boxes and wiring are common. Don't you think that back when BX came into use they were just as smart as we are now and if the OCP (fuse) wouldn't be able to protect they would have figured it out? I think it worked just fine when it was new. So why the problem now? Is oxidation and corrosion over the years the cause? And what about that aluminum bonding strip under steel armor today? Two dissimilar metals.

-Hal

It always had a problem, with out the bonding strip a ground fault can turn the armor into a heating coil.
 

wwhitney

Senior Member
Location
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Occupation
Retired
A)[. . .] In particular, I'm interested in the case where the original installation included an allowance of 2 for the receptacle, but some other change in 314.16 pushed the required box volume above that present. Would you have to change out the box in that case when doing a receptacle replacement?

Again, to keep this simple and on target to the OP scenario, let there be enough cubic inches in the existing box.
Again. Asked and answered. Tail chasing.
Respectfully, you really haven't answered. You've just refused to entertain the question. Which you are free to do, but that's not answering.

B) For (3), contrary to your last statement on the matter, 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. Again. Asked and answered.

Sure, I agree with your first statement. But I think it is important to understand the logical consequences of your position, and I am concerned that branch extension of an existing unbonded BX branch circuit using the cable armor as an EGC is one of those consequences. Respectfully, you have again declined to entertain the question, so you have not answered.

Cheers, Wayne
 
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wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
This thread is at 275+ posts on the NEC with respect to receptacle replacement in an existing Outlet, per the OP, if that's OK?
The OP chose to put this in the General Electrical Forum, rather than in the NEC forum, so he at least is interested in a broader discussion. Of course, you and I have been engaging in a debate about the meaning of the NEC.

But I'm happy to call the NEC debate a draw if you agree with the proposition in post 272.

Cheers, Wayne
 
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