AC or MC cable?

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shocker3218

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I am on a jobsite that the inspector has deemed that the wiring method used 15 years ago was never legal in this city. I am trying to do some research on exactly what the wiring method was. It is 2 wires in a thin aluminum sheathing with no tracer wire, or groung wire. It is very small diameter (about 1/4 inch for 14-2). One person called it Cobra flex?

His contention is that I need to replace all the receptacles in the entire apartment complex with 2 wire receptacles, as this outer sheathing does not count as an equiopment ground. If I can find out what type of product it is, and find the code that governed the installation at the time, perhaps I can fight him on this issue.

I have already replaces all the receptacles once as part of the original bid, so this would be an extra, but it seems strange that 3 wire receptacles were OK on the original install, but now are not OK.

Any help would be appreciated.
 
it is smooth. Similar to what I call EZ flex, or the inner flex in steel liquidtight. Not nearly as corigated as standard 1/2 or 3/4 flex. I am at a severe dis-advantage here because in 20 years of electrical, I have never installled MC or AC.
 
I kind of remember a sample of something like that at the supply house counter about 15 years ago. I believe it was a type of MC which would mean that it had an EGC, maybe there was an AC version. Never saw any actually in use though, I didn't like it.

Kind of hard to believe that something that was manufactured only 15 years ago was not listed for an EG. Maybe problems were discovered after it was in use, kind of like aluminum wiring?

-Hal
 
Just some guesses here, maybe they'll be of help. AC cable is required to have "an internal bonding strip of copper or aluminum, in intimate contact with the rmor for its entire length". This requirement is in the code all the way back to the 1978 edition, which is the oldest NEC I have available. I doubt what you have is AC Cable.

MC cable sheathing is allowed to be of several types, including a corrugated metallic sheath. I have never seen anything other than the interlocking metal tape armor, but the corrugated type must have been made at some time. Maybe it still is? I suspect this is what you have. The 1978, 1987, and 1990 NEC all have this requirement for MC cable: "Type MC cable shall provide an adequate path for equipment grounding as required by Article 250". In all of the NEC editions in which I have looked, Article 250 allows the metallic sheath or the combined metallic sheath and grounding conductors (depending on the type of MC cable) to be used as an equipment grounding conductor. Take a look at 250.118(10) in the 2005 for the current wording. Since the cable you have does not include a grounding conductor, I suspect you have a type with which the sheathing provides the equipment grounding conductor. If you can find evidence to support this conclusion, there should be no problem using grounding type receptacles with the wiring method. The fact that grounding type receptacles were allowed in the original install supports my guess.
 
thanks for your replies. I agree that it must be an older version of MC since there is no bonding strip, ans no ground conductor. I will try to post a picture in the next couple of days. I thought about the GFI breakers, but I would be required to label all receptacles as having "no equipment ground" and remove the ground pigtail from the receptacle. All very time consuming.
 
Sigma Clad is the type I am somewhat familiar with. Round smooth Aluminum sheath.

I don't remember who made it. It was used with two screw connectors that I assume were listed for MC Cable.

At any rate, the inspector should have something to back up this claim. My opinion is that in an existing bldg, the burden of proof is on the AHJ.

Are thay saying it was never inspected?
If it was inspected, I believe they own it. It should come from the Chief Building Official as to the installation of two wire recep's.

As far as the liability if something were to happen; I will have to bow out on that question due to lack of experience and knowledge in those matters.
 
They are actually saying it was never inspected. I find that hard to believe since a new meter stack and underground servise was installed at the same time. Most of the the connectors are two screw type similar to 3/8 romex clamps only a small hole in the bottom of the connector.

It is a round assembly
 
I've installed a lot of this in years past. It was probably 16-18 years ago and I think it was called Sigma Clad or Signa Clad. It wasn't around long for whatever reason. We used it in exposed applications in Burger King restaurants. They had an 'open concept' dining area and it concealed well in the exposed rafters.

I remember we had to buy a special cutting tool almost like a tubing cutter to work with it.
 
shocker3218 said:
They are actually saying it was never inspected. I find that hard to believe since a new meter stack and underground servise was installed at the same time. Most of the the connectors are two screw type similar to 3/8 romex clamps only a small hole in the bottom of the connector.

It is a round assembly
Click to expand...

Permits are public record. You can go down and do your own research in most jurisdictions. Some are computerized and some the old file in a drawer and some are on microfiche.

They "shouldn't" just say it wasn't inspected. They "should" have some proof.

Somebody had to release the service to the POCO!! Usually it's the local jurisdiction.
 
Larry
We have had incidents where services were upgraded, and they have not been inspected by the AHJ. Yet the utility company locked them. This is either because the meter person saw it unlocked and did not do the proper paperwork, or even worse... the contractor knows someone in the utility company and has a "deal" with them.
So one can also contact the utility company and see what their records indicate.
 
Pierre C Belarge said:
Larry
We have had incidents where services were upgraded, and they have not been inspected by the AHJ. Yet the utility company locked them. This is either because the meter person saw it unlocked and did not do the proper paperwork, or even worse... the contractor knows someone in the utility company and has a "deal" with them.
So one can also contact the utility company and see what their records indicate.
Click to expand...

Pierre
It would be great to find the POCO got a release from the AHJ while the AHJ says it was never inspected.

"course they would probably say that was bogus also.

When we had the Olympics here some years back (early 80's), I heard the POCO field crew energized the temp services for tickets to the Olympics.
 
I've had a few almost-upgrades come my way. new SE from the meter to the panel (only), 200a breaker, and a hodge-podge of breaker brands in one. Never permitted, thus never inspected, all required plenty of work to become code compliant.

What kind of work? Oh, nothing major: correct SE for the size, cable clamps, grounding electrodes and pipe bonding, that kind of stuff. Oh, yes. All gloriously heralded by a buyer-hired home inspector. But God forbid there be two wires on a breaker!!!
 
Finally got the chief electrical inspector involved. This project has been on hold for nearly a month waiting for answers, and we were getting nowhere. Chief inspector looked at the wiring method and determined that it was corrugated MC and the sheathing was approved as a grounding method when the proper fittings were used. So the entire issue is now a thing of the past. Our change order for $70,000 to add GFI breakers definately got some attention.
 
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