BX as a ground.

[mbrooke]

This is why I go to great lengths to describe it as "unbonded BX". I assume that AC cable is understood to have the bonding conductor.

Everything you say about old BS is correct. Its simply an in wall heater.

 

[al hildenbrand]

I couldn't possibly care less what HI's do. The question was what do we as professional electricians do about old unbonded BX systems. Unbonded armor is not a recognized EGC, and rightfully so as the impedance is far too high to make a reliable fault path.

The historical National Electrical Code flies in the face of your assertion. I have given references in my posts along with quotes of the original NECs. . . you seem only to be making a claim that this old Code is lying. Can you document for us that pre-1950s Armored Cable type-BX was "not recognized" as a grounding means. The Code does not, at this time, retroactively remove the acceptability of a wiring method installed to the Code of its date of install.

I get that you, Peter, have a strong and clear opinion about pre-1950s Armored Cable type-BX, and that you, as a professional electrician, choose to treat it the way you describe. And if you can get customers to pay you for the exercise of your opinion, fine. To "sell" your customer by misstating the actual National Electrical Code is risky, in my opinion. But it is a business strategy.

Professional electricians will, contrary to the Peter D Electrical Code, use pre-1950s Armored Cable type-BX as a National Electrical Code approved grounding means in existing installations of BX that was installed as part of an equipment grounding path to the Code in effect for the original installation.

 

[peter d]

The historical National Electrical Code flies in the face of your assertion. I have given references in my posts along with quotes of the original NECs. . . you seem only to be making a claim that this old Code is lying. Can you document for us that pre-1950s Armored Cable type-BX was "not recognized" as a grounding means. The Code does not, at this time, retroactively remove the acceptability of a wiring method installed to the Code of its date of install.

I get that you, Peter, have a strong and clear opinion about pre-1950s Armored Cable type-BX, and that you, as a professional electrician, choose to treat it the way you describe. And if you can get customers to pay you for the exercise of your opinion, fine. To "sell" your customer by misstating the actual National Electrical Code is risky, in my opinion. But it is a business strategy.

Yes Al, lots of sophistry to justify that which cannot be justified. Typical for you. I stated my case clearly. If I install wiring in the year 2016, I have to follow modern codes, not ancient and long forgotten NEC rules. I cannot use the armor of BX because it's no longer listed an EGC despite what old documents said. I never said anywhere that the old code is lying, just that it no longer applies to modern extensions or modifications to old unbonded BX cable. I am not "misstating" the code rules. The burden is on you where I'm allowed to use unbonded BX cable as an EGC.

Professional electricians will, contrary to the Peter D Electrical Code, use pre-1950s Armored Cable type-BX as a National Electrical Code approved grounding means in existing installations of BX that was installed as part of an equipment grounding path to the Code in effect for the original installation.

Those "professional" electricians are hacks and are creating a highly dangerous situation by doing so. Early editions of the NEC did not require GFCI protection anywhere, do you then use that same twisted logic and not install GFCI's where they are now required?

 

[al hildenbrand]

I assume that AC cable is understood to have the bonding conductor.

This is part of the difficulty. Your assumption excludes all the armored cable that was manufactured, installed and used by consumers for the first half of the Twentieth Century.

 

[growler]

The 80-90 year old BX we're discussing, like modern Article 330 MC, has a jacket that is no longer an acceptable EGC.

Once you say it doesn't have an acceptble EGC then you may as well say it doesn't have an EGC. So how would you deal with replacement receptacles with old two wire or knob and tube? You can forget the idea of two prong receptacles because that's not what the bank wants. To install three pronged receptacles you would have to GFCI protect the circuit and install " no equipment ground" stickers on all receptacles. Now that you have changed out the receptacles then Arc fault protection is probably required.Then the fun begins.

 

[peter d]

This is part of the difficulty. Your assumption excludes all the armored cable that was manufactured, installed and used by consumers for the first half of the Twentieth Century.

Ok, I get it. You think this stuff is an acceptable EGC. I think by doing so you're literally playing with fire. We are not going to agree on this.

 

[ActionDave]

I agree with Peter, either use two wire recpts or gfci protect the circuit.

 

[user 100]

For the benefit of anyone following this thread who's not familiar with the jargon, or with the conflict between casual talk and strict NEC usage...

Article 320 AC cable, introduced around 1959, includes a bonding wire, aka drain wire, so that its metal jacket is listed and NEC-acceptable for use as an Equipment Grounding Conductor.

The 80-90 year old BX we're discussing, like modern Article 330 MC, has a jacket that is no longer an acceptable EGC.

Casually, "AC" might be used to include old BX, or to MC. And some folk use "BX" to refer to modern AC or MC. But for NEC, or GEC, purposes, they are quite distinct.

I think too that in order for the retroactive/grandfather argument to hold any weight the bx armor would only qualify as an egc if it was approved for such by the NEC/ul during the time period in which the dwelling was wired. A 1956 house then yeah, sure but a 1929 house, I don't think so, unless of course there is an old code passage that states otherwise.

Anyway, even if it would have been allowed thru grandfathering, still not a good idea. You don't want a toaster coil in the wall or someone hit by a ground fault- the amount of res present on many old bx runs it may take minutes or longer for a standard ocpd to trip. Like I said earlier in the thread, imo, there was obviously lot of ignorance years ago about impedance and thus the poorly bonded sheath as egc was allowed because of ignorance.

Today we know better- a high resistance path for fault current back to source is considered dangerous and almost unthinkable and we have acceptable alternatives (like gfci) to effectively eliminate the hazard- I say on this issue to leave the '50's style thinking in the '50's.

GFCI, 2 wire recs, or rewire.

 

[al hildenbrand]

lots of sophistry to justify that which cannot be justified. Typical for you.

soph·ist·ry -- the use of fallacious arguments, especially with the intention of deceiving.

So you are saying, again, that my quotes from the NEC are lies.

I cannot use the armor of BX because it's no longer listed an EGC despite what old documents said.

Well, if it is not your opinion that binds you, it is what? Local ordinance? It's not the NEC, in spite of your assertion.

I am not "misstating" the code rules. The burden is on you where I'm allowed to use unbonded BX cable as an EGC.

Already shown to you. So far you have given only strong opinion.

 

[mbrooke]

The historical National Electrical Code flies in the face of your assertion. I have given references in my posts along with quotes of the original NECs. . . you seem only to be making a claim that this old Code is lying. Can you document for us that pre-1950s Armored Cable type-BX was "not recognized" as a grounding means. The Code does not, at this time, retroactively remove the acceptability of a wiring method installed to the Code of its date of install.

I get that you, Peter, have a strong and clear opinion about pre-1950s Armored Cable type-BX, and that you, as a professional electrician, choose to treat it the way you describe. And if you can get customers to pay you for the exercise of your opinion, fine. To "sell" your customer by misstating the actual National Electrical Code is risky, in my opinion. But it is a business strategy.

Professional electricians will, contrary to the Peter D Electrical Code, use pre-1950s Armored Cable type-BX as a National Electrical Code approved grounding means in existing installations of BX that was installed as part of an equipment grounding path to the Code in effect for the original installation.

The old code clearly is lying then. The bonding strip was added for a reason, otherwise we would still have armored cable without bonding strips. If you would like to prove us wrong, first show us the reason why the bond strip was added...

 

[user 100]

The old code clearly is lying then. The bonding strip was added for a reason, otherwise we would still have armored cable without bonding strips. If you would like to prove us wrong, first show us the reason why the bond strip was added...

Ignorance,mbrooke, not lying- again, today we are head and shoulders above the old guys when it comes to understanding of ocpd's opening and resistance. The code bx bonding probably changed because of a greater understanding (and probably b/c of failures too) about that issue.

 

[mbrooke]

Ignorance,mbrooke, not lying- again, today we are head and shoulders above the old guys when it comes to understanding of ocpd's opening and resistance. The code bx bonding probably changed because of a greater understanding (and probably b/c of failures too) about that issue.

True, perhaps ignorance would better explain it as I dont think old CMP members way back when actually wanted fires, but I agree with Peter D 100%. Old BX is not a reliable EGC.

 

[romex jockey]

For the benefit of anyone following this thread who's not familiar with the jargon, or with the conflict between casual talk and strict NEC usage...

Article 320 AC cable, introduced around 1959, includes a bonding wire, aka drain wire, so that its metal jacket is listed and NEC-acceptable for use as an Equipment Grounding Conductor.

The 80-90 year old BX we're discussing, like modern Article 330 MC, has a jacket that is no longer an acceptable EGC.

Casually, "AC" might be used to include old BX, or to MC. And some folk use "BX" to refer to modern AC or MC. But for NEC, or GEC, purposes, they are quite distinct.

Historian Al, how'd I do?

So basically BX was installed prior to the debut of an ecg , which it was never intended by it's manufacturer(s) to be.

~RJ~

 

[peter d]

soph·ist·ry -- the use of fallacious arguments, especially with the intention of deceiving.

So you are saying, again, that my quotes from the NEC are lies.

Not lies, but certainly irrelevant and throwing sand in the eyes of those trying to understand this issue better. 1950's era NEC code rules are not relevant and certainly don't apply to modifications made to old BX cable in 2016. You're not a dumb guy but you're certainly using a dumb argument on this one.

Well, if it is not your opinion that binds you, it is what? Local ordinance? It's not the NEC, in spite of your assertion.

Already shown to you. So far you have given only strong opinion.

Please show me in the current edition of the NEC where unbonded BX cable armor is listed as a suitable EGC.

Also, please explain (as another member pointed out) why AC cable (an evolution of unbonded BX) included in its construction a bonding wire across all armor spirals?

 

[peter d]

The old code clearly is lying then. The bonding strip was added for a reason, otherwise we would still have armored cable without bonding strips. If you would like to prove us wrong, first show us the reason why the bond strip was added...

I agree with user100, ignorance was the case here. Remember that in the 1950's and earlier, there was asbestos on pipes and boilers, people smoked cigarettes like chimneys anywhere and everywhere, lead paint was the norm, ballasts were filled with PCB's, toxic and chemical waste was dumped directly into rivers and waterways, racial segregation was alive and well...I could go on. We've progressed and learned from those past blunders. Obviously later editions of the NEC recognized this serious deficiency in unbonded BX and changed accordingly.

 

[mbrooke]

I agree with user100, ignorance was the case here. Remember that in the 1950's and earlier, there was asbestos on pipes and boilers, people smoked cigarettes like chimneys anywhere and everywhere, lead paint was the norm, ballasts were filled with PCB's, toxic and chemical waste was dumped directly into rivers and waterways, racial segregation was alive and well...I could go on. We've progressed and learned from those past blunders. Obviously later editions of the NEC recognized this serious deficiency in unbonded BX and changed accordingly.

I agree, and good chance its actually that. Remember that at one point in history electricians were trained to check for voltage by touching the wires.

 

[al hildenbrand]

Remember the OP? This is the question:

can you use the outer casing on bx as a ground while adding self grounding outlets and putting a gfci breaker in at the panel be good.

To which the first answer was:

If it is the old BX without the bonding strip then the sheathe should not be used as an equipment ground. Look at 250.130(C) and 406.4(D).

That answer is only accurate if the "old BX" is being INSTALLED now in new construction.

Obviously later editions of the NEC recognized this serious deficiency in unbonded BX and changed accordingly.

Peter, the question is not about installing new runs of pre-1950s Armored Cable type BX in new installations.

The OP question is about receptacle replacement in an existing dwelling that was originally wired to the Code in effect at the time of its construction with "unbonded" armored cable type BX.

What you are effectively doing, by claiming that nothing short of total BX replacement should be done, is throw up an economic barrier to those who are maintaining the Premises Wiring (System). They withdraw from repairing worn receptacles because of your opinion. Who's creating the risk?

 

[al hildenbrand]

I think too that in order for the retroactive/grandfather argument to hold any weight the bx armor would only qualify as an egc if it was approved for such by the NEC/ul during the time period in which the dwelling was wired. A 1956 house then yeah, sure but a 1929 house, I don't think so, unless of course there is an old code passage that states otherwise.

Anyway, even if it would have been allowed thru grandfathering, still not a good idea. You don't want a toaster coil in the wall or someone hit by a ground fault- the amount of res present on many old bx runs it may take minutes or longer for a standard ocpd to trip. Like I said earlier in the thread, imo, there was obviously lot of ignorance years ago about impedance and thus the poorly bonded sheath as egc was allowed because of ignorance.

Today we know better- a high resistance path for fault current back to source is considered dangerous and almost unthinkable and we have acceptable alternatives (like gfci) to effectively eliminate the hazard- I say on this issue to leave the '50's style thinking in the '50's.

GFCI, 2 wire recs, or rewire.

I have a copy of the 1918 NEC open at the moment, and little time left at the moment. . . my apologies for brevity,

The 1918 NEC grounding means on the armor of armored cable is in place then.

 

[Fulthrotl]

True, perhaps ignorance would better explain it as I dont think old CMP members way back when actually wanted fires, but I agree with Peter D 100%. Old BX is not a reliable EGC.

well, the NEC is an evolving document.

sometimes the driving forces are altruistic, sometimes crassly commercial,
and subject to the judgement of the person(s) making the call.

BX, Aluminum Romex, AFCI breakers. all part of the code at one point in time.

unless i'm mistaken, as a group of [professionals] the only thing we can absolutely
agree on, is ground up, or ground down, right?

all two wire ungrounded systems should have the 3 wire grounded receptacle
installed ground UP, so we know it's not to be depended upon... correct?



and when this horse is dead, can we please discuss something less controversial,
like gun control?

 

[mbrooke]

Remember the OP? This is the question:

To which the first answer was:

That answer is only accurate if the "old BX" is being INSTALLED now in new construction.


Peter, the question is not about installing new runs of pre-1950s Armored Cable type BX in new installations.

The OP question is about receptacle replacement in an existing dwelling that was originally wired to the Code in effect at the time of its construction with "unbonded" armored cable type BX.

What you are effectively doing, by claiming that nothing short of total BX replacement should be done, is throw up an economic barrier to those who are maintaining the Premises Wiring (System). They withdraw from repairing worn receptacles because of your opinion. Who's creating the risk?

Not advocating replacement, simply it not be used as an EGC.