BX as a ground.

Status
Not open for further replies.

iwire

Moderator
Staff member
Location
Massachusetts
I picked up a feed for an under cab light and a DW from this old BX.

Would not use it as an EGC much more comfortable with my scotch 33 ground clamp to the waterline.

Now I don't do this hack work on the job but I show you this mess as a way to show I won't use old BX as an EGC.
 

Attachments

  • IMG_20160118_155341.jpg
    IMG_20160118_155341.jpg
    143 KB · Views: 1
  • IMG_20160118_155306.jpg
    IMG_20160118_155306.jpg
    146.6 KB · Views: 1

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
I disagree that there is an EXISTING EGC. There is a ground path, which the current NEC no longer judges to qualify as an EGC. Act accordingly.

Cheers, Wayne
Seriously, Wayne?

Before I touch the coverplate on the existing grounding-type receptacle, it is installed to the Code of it's original install, and IS connected to a grounding means then recognized (the early 1970s FMC), and is, in fact, electrically grounded. . .

I have given a reading of 406.4(C) first sentence just a little earlier in this thread that maintains the existing grounding means.
 

iwire

Moderator
Staff member
Location
Massachusetts
Before I touch the coverplate on the existing grounding-type receptacle, it is installed to the Code of it's original install, and IS connected to a grounding means then recognized (the early 1970s FMC), and is, in fact, electrically grounded. . .

And it was properly grounded back in 1970 but now in 2016 you want to install a NEW outlet and that old BX is not compliant for new work. You agreed with me on that a few posts ago.
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
And it was properly grounded back in 1970 but now in 2016 you want to install a NEW outlet and that old BX is not compliant for new work. You agreed with me on that a few posts ago.
I agree for a NEW outlet, but I am staying with the question about an EXISTING outlet that is being maintained by receptacle replacement. Replacing the device with a grounding type, nongrounding type, GFCI, or OBC AFCI, the "outlet" is still a "receptacle outlet", an existing outlet. No new outlet.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
Seriously, Wayne?
Yes, seriously. What's so hard about the idea that something can be compliant under the code at the time of installation, but subsequent code changes render it non-compliant?

Before I touch the coverplate on the existing grounding-type receptacle, it is installed to the Code of it's original install, and IS connected to a grounding means then recognized (the early 1970s FMC)
Yes, then recognized, but no longer. You're not replacing the receptacle in the 1970's, you're replacing it today.

, and is, in fact, electrically grounded. . .
Yes, but not well enough for the current NEC. It is not connected to a currently recognized EGC.

I have given a reading of 406.4(C) first sentence just a little earlier in this thread that maintains the existing grounding means.

2011 NEC said:
406.4(C) Methods of Grounding. The equipment grounding conductor contacts of receptacles and cord connectors shall be grounded by connection to the equipment grounding conductor of the circuit supplying the receptacle or cord connector. The branch-circuit wiring method shall include or provide an equipment grounding conductor to which the equipment grounding conductor contacts of the receptacle or cord connector are connected.
To satisfy this rule you need an equipment grounding conductor. That would be something that is listed under 250.118 in the current NEC. No explicit direction to 250.118 is required in 406.4(C); the phrase 'equipment grounding conductor' is enough. As a bonus we get an informational note to remind use to look in 250.118 to evaluate whether we have an EGC.

So absent any EGC listed under 250.118, we can not comply with 406.4(C). That would apply to old style BX or FMC of excessive length.

Your attitude seems to be "it was compliant at the time of the install, I'm only touching the receptacle, so I don't need to look at anything else." By that logic, if you were replacing a receptacle in a box where EMT is the EGC and you notice that one of the nearby couplings had come loose, you could ignore it because you are only touching the receptacle. In both cases you have evidence of a compromised grounding path, and in both cases you need to fix it before installing a replacement grounding type receptacle.

Cheers, Wayne
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
To satisfy this rule you need an equipment grounding conductor. That would be something that is listed under 250.118 in the current NEC.
You are misquoting the rule of 406.4(C) by not separating the two sentences and adding the two different numbering systems of the Informational Notes. This is misleading, IMHO. I contend the rule is in two parts, as written and formatted. This offers at least a second interpretation which I have explained in this thread . . . an interpretation that does NOT take us to 250.118.
Your attitude seems to be "it was compliant at the time of the install, I'm only touching the receptacle, so I don't need to look at anything else." By that logic, if you were replacing a receptacle in a box where EMT is the EGC and you notice that one of the nearby couplings had come loose, you could ignore it because you are only touching the receptacle. In both cases you have evidence of a compromised grounding path, and in both cases you need to fix it before installing a replacement grounding type receptacle.
Wayne, I'm making a Code argument, not a workmanship argument. I'm trying to find the Code that makes existing legal wiring no longer legal. What ends grandfathering? A loose coupling hypothetical in the area that MAY be present is another thread.
 

iwire

Moderator
Staff member
Location
Massachusetts
YI'm trying to find the Code that makes existing legal wiring no longer legal.

The entirety of the latest code. (Much as George S posted before, but you seem to have missed or ignored.)

This does not mean what is existing is now non-compliant or has to be ripped out it just means you can't use the old wiring for new work.


Al, I mean no disrespect at all but I really can't understand your position or what you are not seeing. :(
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
New receptacle = new work absent any allowances to the contrary by the current NEC.
Yes, I agree . . . BUT it is a new device (new "work") and no more. The Receptacle Outlet that existed still exists and is not NEW. No NEW receptacle outlet has been added.
 

iwire

Moderator
Staff member
Location
Massachusetts
Yes, I agree . . . BUT it is a new device (new "work") and no more. The Receptacle Outlet that existed still exists and is not NEW. No NEW receptacle outlet has been added.

You installed a new receptacle, new receptacles require compliance with today's code. Old BX is not in compliance with today's code or listing standards.
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
The entirety of the latest code. (Much as George S posted before, but you seem to have missed or ignored.)

This does not mean what is existing is now non-compliant or has to be ripped out it just means you can't use the old wiring for new work.


Al, I mean no disrespect at all but I really can't understand your position or what you are not seeing. :(
I haven't gotten back to George's response in his quote from page four of the NEC. . . the NEC is a new construction standard. That's the sticker, to me.

I don't think I'm missing anything. I'm frankly surprised at how divergent folks here on the Forum are in their declaration of my error, compared to the Real World of my area of work. And I'm willing to hold forth with an attempt to understand the legal end of grandfathered installations.

new receptacles require compliance with today's code.

Yes, new RECEPTACLE devices DO. . . but no new OUTLET is added, so the EXISTING outlet is still viable. The EXISTING outlet has a grounding means delivered by the branch-circuit wiring method, and from its Code in effect when installed. IMHO, nothing has ended that.
 

Gene B

Member
Location
USA
Can we agree that no EGC (with GFCI) is more hazardous than a non-Code-compliant EGC (also with GFCI)?

Because the former is NEC legal for old construction, and not only in bathrooms.

So if somebody hits you over the head with NEC, just point out that what you're doing is safer than what is explicitly allowed.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
You are misquoting the rule of 406.4(C) by not separating the two sentences and adding the two different numbering systems of the Informational Notes.
I disagree. The informational notes are just that, pointers to other sections of the code to be aware of. Deleting them does not change the meaning of the code. They are just guides to helping you understand the code. For example, one of the informational notes there directs you to 250.118, but an informed reader already knows that you need to go to 250.118 to see if you have an EGC. The informational note is a guide for the uninformed reader.

As to separating the two sentences, I see the second sentence as redundant. To paraphrase, sentence 1 says "connect the ground prong on the receptacle to the EGC." That implies there has to be an EGC. Sentence 2 says "the branch circuit has to provide an EGC." We already knew that, because if there's no EGC in the branch circuit, we can't connect to it.

This offers at least a second interpretation which I have explained in this thread . . . an interpretation that does NOT take us to 250.118.
You seem fond of that argument, but it makes no sense. The first sentence of 406.4(C) tells us to connect to the EGC. That immediately means to check 250.118 to see if we have an EGC. BX without a bonding strap does not provide an EGC (anymore), so we can't comply with 406.4(C). QED.

In your earlier argument you wrote:
At this point, and this is the heart of my position, NOTHING is said that defines the nature of the "existing grounding means."
The word "existing" does not occur in 406.4(C) outside of the informational note. Informational notes are not code.

Also, "grounding means" is not used in 406.4(C). Only the term EGC is used, which unequivocably means one of the things listed in 250.118. A box fed only with BX cable lacking a bonding strap has no EGC.

Cheers,
Wayne
 
I am on mobile so short answer for now.
To me digraming a code section is a waste of time and only serves as a means to show ones own abilities.
I would be shocked if any CMP has diagramed a code section before adding it to the code.
Bottom line for me is simple this, old BX is not constructed as the present standards require therefore I can not use it for new work / grounding of new work.
I am not saying what is in place has to go, I am simply saying that if I add to a BX circuit I don't have a code compliant ground to use for the new wiring.

Not nice. Of course the CMP doesn't diagram their sentences. No normal person diagrams their sentences! The only reason I did what I did (which wasn't a diagram at all, really) was to try to explain Al's mis-reading of 250.130.

You and I agree on the conclusion, iwire, but Al is holding out for code support. It's in there: whenever you replace a non-grounding receptacle with a grounding one, it's made explicit via 250.130 (C) that you must involve a currently-acceptable EGC by the standards of 250.118.

Looking at the first part of 250.130, Al thought the restriction, "
only in existing installations that do not have an equipment grounding conductor in the branch circuit", took 250.130(C) out of the picture entirely. But take another look: that restriction follows "and for branch circuit extensions". It doesn't apply to the previous phrase "For replacement of non–grounding-type receptacles with grounding-type receptacles".

So you can't evade 250.118, because 250.130(C) says so. And the start of 250.130 doesn't get you out of this.

Here's why I'm so sure I'm right about this: If the CMP had wanted the "only in..." to cover both phrases, they wouldn't have written "and for". Compare these:

(a) For dogs and for cats only if they're not ugly you must smile at them.
(b) For dogs and cats only if they're not ugly you must smile at them.
I think you must smile at ALL the dogs in (a), but maybe only the pretty ones in (b).

And (a) is how 250.130(C) is written: you smile at all the dogs. You reference 250.130(C) for all the ungrounded-to-grounded receptacle replacements.

Bitter realization of the obvious:
Y'know, if the NFPA had hired one good copy-editor, then this forum would have a lot less argument, the wolf would dwell with the lamb, and iwire would love all his fellow forum members.

A comma or two would've made this all very obvious, but this CMP couldn't be bothered. Or maybe they have a commitment to the Forensic Linguist Full-Employment Movement.
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
Thank you for a thoughtful analysis. I think you've made a good point, but I will come back to it after coffee tomorrow. There is only one fly in your ointment, I think:

it's made explicit via 250.130 (C) that you must involve a currently-acceptable EGC by the standards of 250.118.
"250.118" does not appear anywhere in the text of all of 2014 NEC 250.130.
 
There is only one fly in your ointment, I think:
it's made explicit via 250.130 (C) that you must involve a currently-acceptable EGC by the standards of 250.118.
"250.118" does not appear anywhere in the text of all of 2014 NEC 250.130.

Indeed it does not. Would you believe It's "made explicit" only in the depraved sense such the phrase that might apply to the NEC?

250.130(C) does demand an EGC, and its the Article 100 definition of EGC that references 250.118

So you are pointed toward 250.118, but you are taking the long way there.
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
Forgive me for the length. We are in the center of the matter, finally.

250.130(C) does demand an EGC, and its the Article 100 definition of EGC that references 250.118

So you are pointed toward 250.118, but you are taking the long way there.
In the opening of the rule 250.130 last sentence that guides us to 250.130(C), I'm not finding the instructions to install an EGC (2014 defined) nor am I finding the instructions to use only an EGC as defined by today's Code, which you, as you are reading it, seem to be finding.

This is interesting. Somehow the NEC terminates the "grandfathered" installed to the Code of its original installation status as a "grounding means" of two different wiring methods -- 1.) Armored Cable type BX, 2.) Flexible Metal Conduit of over six feet aggregate length.

Armored Cable type BX was manufactured and installed in an era of nongrounding-type receptacles being predominant, however, when required GROUNDING-type receptacles were installed, they were grounded by the device screws attachment to the receptacle outlet box (as was the Code of that day) because the BX was installed as a grounding means per that day's Code.

Flexible Metal Conduit (FMC) is also a wiring method that has had its status as an EGC altered as the Code editions have evolved, although FMC has not had to have its manufacturing altered. The metal of FMC was recognized as a grounding means, regardless of length, until the "6 feet" restriction of the 1971 NEC 250-91(b) Exception No. 1(a.) appeared for the first time. All receptacle devices installed at that time had to be of the grounding-type, and that had been true since the 1962 NEC was adopted.

Also, parenthetically, note that 1968 NEC Article 100 Definitions has the FIRST appearance of the defined term "Grounding Conductor, Equipment". For the first almost 3/4 century of the NEC, the EGC was NOT called the EGC.

In my work area, there was a housing boom, post WWII, that was in full swing, and an existing local ordinance(s) that prohibited NONmetallic wiring methods like NM. Some areas are almost 100% FMC, others are almost 100% Armored Cable and, depending on date of construction, are either type BX or type AC. Infill new construction, and new additions / remodels will be scattered all over the Metro area and ALL this new construction is matching to the work found in NEW Occupancy ADDITIONS to the Metro Area. (However, if one got out far enough from City Center, the "all-metal" ordinances didn't reach, and NM was the primary wiring method.)

My State has had an Electrical Act at the level of State Wide Statute, with enforcement, since 1899. Yes, EIGHTEEN ninety nine. There are a lot of good minds here. The cognitive dissonance I experience between the certainties in this thread about BX and FMC, and the Real World of my work area outside my door is high.

Somewhere, something is being missed. . . here, this thread, has said I am missing it, that the Code is clear. OK. Show it to me.

The immediate rejoinder is "look at 250.118." But, Why?

How, in a "receptacle replacement" in an existing outlet that starts in 406.4, does the Code, not you, or your opinion, does the Code narrow an existing outlets wiring method's existing grounding means to the choices ONLY in 2014 NEC 250.118?

Netpog, I see your point and agree that the first part of 250.130 reads as follows:
2014 NEC
VII. Methods of Equipment Grounding
250.130 Equipment Grounding Conductor Connections.
. . . For replacement of nongrounding-type receptacles with grounding-type receptacles . . . , connections shall be permitted as indicated in 250.130(C).

So, when I am ONLY replacing a receptacle device (that is, I am not installing a NEW branch circuit extension or NEW EGC with the branch circuit conductors) in an existing "outlet" that has an "existing" "conductive(s) path 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," (Note that this is the Definition of Grounding Conductor, Equipment from Article 100.) I check that "connections" are as "permitted" in 250.130(C).

Bear with me now, I will return to this last sentence, "I check that 'connections' are as 'permitted' in 250.130(C)."

But I have two "or" in the logic tree that leads me to 250.130(C), and they are back in 406.4(D)(1) in that one-sentence-rule.

This is the start of "receptacle replacement" as I see it.
406.4 General Installation Requirements. Receptacle outlets shall be located in branch circuits in accordance with Part III of Article 210. General installation requirements shall be in accordance with 406.4(A) through (F).
(D) Replacements. Replacement of receptacles shall comply with 406.4(D)(1) through (D)(6), as applicable.
(1) Grounding-Type Receptacles. Where a grounding means exists in the receptacle enclosure or an equipment grounding conductor is installed in accordance with 250.130(C), grounding-type receptacles shall be used and shall be connected to the equipment grounding conductor in accordance with 406.4(C) or 250.130(C).
(2) Non–Grounding-Type Receptacles. Where attachment to an equipment grounding conductor does not exist in the receptacle enclosure, the installation shall comply with (D)(2)(a), (D)(2)(b), or (D)(2)(c).
I only have to know that a grounding means exists. Earlier Codes in effect at the time of installation, establish the grounding means existence, at that time.

Because of the first "or" I do not have to look further, I skip EGC (because no new EGC is being installed), and read "shall be connected to the equipment grounding conductor in accordance with 406.4(C) or 250.130(C)," and I choose 250.130(C). I don't have a choice in this matter about the grounding-type receptacle, even if the existing receptacle device that I am to replace is an nongrounding-type, because I HAVE to use a grounding-type "Where a grounding means exist".

"But" you say, "it says you have to connect to the "equipment grounding conductor" which puts you in 250.118 which, in turn, says BX, or >6' lengths of FMC, are not grounding means. . .

Paradox. We're only at this use of "equipment grounding conductor" because of "Where a grounding means exists in the receptacle enclosure" . . . The old Codes unambiguously establish the armor of "armored cable", without restriction, as a grounding means as I have quoted them from 1918 until 1959.

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).

And there I have returned us to 250.130(C). We never went to 406.4(C) because of the "or".

As I have said from the very beginning of this thread, the problem is everybody can't use 250.118 without first arriving at it through the NEC, by which I mean, one can't start by assuming that old non-bonding strip BX was NEVER a grounding means.

The original BX Code approved installation as a grounding means is preserved until it is removed by the NEC. I've just shown a path through today's 2014 NEC that makes use of that existing older Code status. I think it is correct. Regardless, if my opinion, where is the Code cited wrong?
 
Last edited:

iwire

Moderator
Staff member
Location
Massachusetts
Not nice.

I am not known as Mr Sunshine. :D But you did ask me a direct question and I gave you my honest opinion.

Of course the CMP doesn't diagram their sentences. No normal person diagrams their sentences! The only reason I did what I did (which wasn't a diagram at all, really) was to try to explain Al's mis-reading of 250.130.

But then you asked me about your diagramming it and what I thought of it.

You and I agree on the conclusion, iwire,

Yes.
 
Status
Not open for further replies.
Top