Older panel revisited

[tonype]

Ca. 1960's high rise so I know it is difficult to compare with what we do today. However, am I correct that the presence of metal lath within the "space" of the panel (behind the cover) would have been considered a defect then?

In addition, the cover does not rest squarely with the panel - sits flush with the plaster and is attached with very long screws. When the cover was removed, an air current was detected - I'm guessing this is the cause of the dirt in the panel. Didn't the cover have to mate squarely with the panel?

http://i15.photobucket.com/albums/a352/TonyPE/P1160381.jpg

 

[infinity]

Here's the current requirement. Not sure if it was applicable in 1960.

312.3 Position in Wall.
In walls of concrete, tile, or other noncombustible material, cabinets shall be installed so that the front edge of the cabinet is not set back of the finished surface more than 6 mm (? in.). In walls constructed of wood or other combustible material, cabinets shall be flush with the finished surface or project therefrom.

 

[480sparky]

Here's the current requirement. Not sure if it was applicable in 1960.

From the 1962 NEC:

372-3. Position in Wall. In walls of concrete, tile or other noncombustible material, cabinets shall be so installed that the front edge of the cabinet will not be set back of the finished surface more than ? inch. In walls constructed of wood or other combustible material, cabinets shall be flush with the finished surface or project therefrom.

Oh, wait, you just said that. The language goes back to at least 1937

 

[LarryFine]

That panel may not be original to the building.

 

[macmikeman]

I see this alot in older high rise buildings built back in the 1960's. But here they didn't have a building code and permits, and inspections, and contractor license until around 1967. So all old junk that wouldn't meet the Nec then, is grandfathered as is. Mess with it and you have to fix it though. That is when all the fun part starts.

 

[hurk27]

I have seen many of those Square D panels with an extension ring added to make it flush with thicker plaster or wall board, but they would be hard to find now.

Also keep in mind that older BX can't be used as a grounding path unless it has the bare shorting wire in it.

It also appears that this is a 3-wire feed H,H,N and there is no bonding of the neutral bar (empty hole to the right of center) unless there is a grounding conductor in the main feeder?

 

[infinity]

Also keep in mind that older BX can't be used as a grounding path unless it has the bare shorting wire in it.

Are you sure that is true? If my memory serves me correctly the bonding strip was added to enhance safety but did not mean that cables without it couldn't be used for grounding.

 

[al hildenbrand]

If my memory serves me correctly the bonding strip was added to enhance safety but did not mean that cables without it couldn't be used for grounding.

Correct. The NEC recognized the sheath of old (non bonding strip) armored cable as a grounding means. I traced it back, in the my copies of the NEC, back into the Thirties.

So, unless some hazard is present, the old style BX, in an "as originally installed and inspected" state, in my experience, is still a grounding means.

 

[hurk27]

Correct. The NEC recognized the sheath of old (non bonding strip) armored cable as a grounding means. I traced it back, in the my copies of the NEC, back into the Thirties.

So, unless some hazard is present, the old style BX, in an "as originally installed and inspected" state, in my experience, is still a grounding means.

I would say that just because it was a recognized method for grounding that was reversed in 1959 when the bonding wire was required, we must also remember back then 2-wire receptacles was the norm, and most loads didn't require an EGC, but after the problem of the rust causing the old style of armored cable to become an non-efficient grounding path, which has been the results of many fires documented across the country, I would say any 3-prong receptacles that have been installed, were installed after this defect was discovered, and would not be covered by any grandfather clause, and would not be installed in a code compliant way if they were installed after the 1959 change to the NEC requiring AC cable to have a bonding strip, because after this point the NEC and UL does not recognize the sheath of AC cable for a grounding path if it does not have the bonding strip.

so my statement stands, after 1959 it was against code to install a 3-wire receptacle on a circuit using old style AC cable as a EGC, and since most 3-wire receptacles was not installed till after this point they were not legal by code.

try searching the forum for "armored cable" and then go back to the many early post and you will find many threads on this subject and links to support this.

 

[al hildenbrand]

. . . after 1959 it was against code to install a 3-wire receptacle on a circuit using old style AC cable as a EGC, and since most 3-wire receptacles was not installed till after this point they were not legal by code. . .

The type of outlet installed on non bonding strip BX legally installed before 1959 did not determine whether the wiring method was a grounding wiring method.

 

[al hildenbrand]

The type of outlet installed on non bonding strip BX legally installed before 1959 did not determine whether the wiring method was a grounding wiring method.

There's an interesting parallel in flexible metallic conduit (FMC).

FMC was an approved grounding means until the Eighties, at which point the NEC required the addition of a grounding conductor when more than six feet of FMC was to be used as a grounding means.

A grounding type receptacle, installed prior to the Eighties, when replaced with a new grounding type receptacle, in my experience, does not require the installation of a new grounding conductor within the run of FMC, as the FMC is still a grounding means as originally installed.

If, however, I pull in new conductors in the existing FMC, I add a grounding conductor.

 

[hurk27]

The type of outlet installed on non bonding strip BX legally installed before 1959 did not determine whether the wiring method was a grounding wiring method.

No but the change to the 1959 NEC did.
here is an excerpt from article 80.9(C) which many states have adopted in to regular building laws concerning existing work:

Electrical wiring added to an existing service, feeder, or branch circuit shall not result in an installation that violates the provisions of the Code in force at the time the additions are made.

Simply this means the receptacle being changed to a 3-wire would also be required to have a grounding path method that is recognized by the NEC at the time of the installation of the receptacle, and old AC cable doesn't have that for any receptacle installed after 1959.

To even put this into a different perspective, what about liability, if a fault was to occur and the place burns down because of the AC cable heating up like a toaster element, who are they going to go after. most likely the person who installed the 3-wire receptacle on the old AC cable.

AC cable has not been reconized as a grounding method since 1959, the proof is that UL and the NEC made a change to require a shorting wire in it.

 

[hurk27]

There's an interesting parallel in flexible metallic conduit (FMC).

FMC was an approved grounding means until the Eighties, at which point the NEC required the addition of a grounding conductor when more than six feet of FMC was to be used as a grounding means.

A grounding type receptacle, installed prior to the Eighties, when replaced with a new grounding type receptacle, in my experience, does not require the installation of a new grounding conductor within the run of FMC, as the FMC is still a grounding means as originally installed.

If, however, I pull in new conductors in the existing FMC, I add a grounding conductor.

so with this one could say that just changing the type of receptacle should not require us to add a ground to non-grounded NM, and 406(D) was written for nothing? as the wiring method was legal at the time it was installed.

Edited to add: I have to agree that since the 3-wire receptacle was legal before the replacement and replacing it with a like receptacle would most likely be legal and protected by the grandfather clause, but we are talking about non-grounding receptacles being replaced with grounding receptacles, where the wiring method doesn't support the grounding method required by the code at the time of the replacement.

 

[al hildenbrand]

so with this one could say that just changing the type of receptacle should not require us to add a ground to non-grounded NM, and 406(D) was written for nothing? as the wiring method was legal at the time it was installed.

Edited to add: I have to agree that since the 3-wire receptacle was legal before the replacement and replacing it with a like receptacle would most likely be legal and protected by the grandfather clause, but we are talking about non-grounding receptacles being replaced with grounding receptacles, where the wiring method doesn't support the grounding method required by the code at the time of the replacement.

Again, the type of outlet on the end of the wiring method has nothing to do with whether the method is a grounding means.

Grounding type receptacles were required in specific locations, historically, prior to the 1959 NEC. When those certain grounding type receptacles were supplied by a non bonding strip BX wiring method, it sounds like you would allow the grounding type receptacle to be replaced with a grounding type receptacle, i.e., allow the BX to continue to be used, as it was when it was installed, as a grounding means.

However, it also sounds like you're also saying that the old BX can't be a grounding means, period.

The last sentence of Annex H 80.9(C) is for "additions". Replacing a existing receptacle is not an addition in my opinion.

The first sentence of Annex H 80.9(C) is more on target, including "alterations, or repairs" and permitting the AHJ to establish what parts of the current NEC an existing installation must comply with. Continuing to use BX as a grounding means, in existing pre 1959 installations, doesn't "present an imminent danger to occupants" (Annex H 80.9(B)).