Old EGC style, which code cycle?

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KWillis

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Location
San Jose, Calif.
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Electrical Engineer, Handyman
I have a California residence built in 1962.


The EGC is a bare 14 awg wire run separately to metal outlet boxes in the kitchen, bathrooms, garage and outdoor boxes. It generally follows the 12 awg fabric wrapped NM, but not always, usually under the same staples and branches off with barrel crimped additions as needed, even to different circuits. The EGC is bonded to the boxes with grounding clips. Non-bonded boxes, such as switch boxes, are made of Bakelite.

It is an interesting solution. I am wondering which NEC code cycle this stopped being practiced, and when did grounding conductors need to be included in the cable. My searches has been fruitless.
 

user 100

Senior Member
Location
texas
I have a California residence built in 1962.


The EGC is a bare 14 awg wire run separately to metal outlet boxes in the kitchen, bathrooms, garage and outdoor boxes. It generally follows the 12 awg fabric wrapped NM, but not always, usually under the same staples and branches off with barrel crimped additions as needed, even to different circuits. The EGC is bonded to the boxes with grounding clips. Non-bonded boxes, such as switch boxes, are made of Bakelite.

It is an interesting solution. I am wondering which NEC code cycle this stopped being practiced, and when did grounding conductors need to be included in the cable. My searches has been fruitless.

FWIU, Nm with a reduced size egc in the jacket was available in the the late '50s (a lot of contractors didn't use it and instead did what you mentioned above, as the egc reqs were spotty at the time) and become commonplace around the time the code required all recs to be grounded in 1962 (your house was built then, but may not have adopted the '62 NEC at the time of construction....)- I don't know when the NEC dictated an egc be included in the jacket- I'd imagine it would be around that same time. NM with a full size egc was mandated around 1970 or so....

What you described is very typical for that time period- only recs in certain areas (like the areas you mentioned) were required to be grounded. One old NEC rule was that metal boxes within x number of feet of grounded objects (plumbing) were to be grounded- you'll see grounded boxes/ recs in old kitchens near the sink, but the ones near the dinner table across the room won't be.

They would also bond the metal shell light fixtures in those areas by running that separate egc beside the 2w nm to the ceiling box- very common to see the light and even the light switch box in an old bath grounded thru an egc snaked thru the wall and clamped to the old galvanized plumbing.

FWIW, the separate egc method is still sort of permitted- see 250.130(C)
 
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al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
FWIU, Nm with a reduced size egc in the jacket was available in the the late '50s (a lot of contractors didn't use it and instead did what you mentioned above, as the egc reqs were spotty at the time)
Wow. I've lived a sheltered life. And I worked as an apprentice during my summers in college and installed that ole' reduced EGC NM in a lot of new construction.

I've never seen that kind of installation. I can imagine it was a way to use up the existing stock of non-EGC NM . . .

I can also imagine that is was a way to give an inspector what the new Code required . . .

I agree that the 1962 NEC was the edition of the Code that introduced the requirement that all receptacles be grounding type. The rules in the '62 edition would have only gone into effect when adopted by the local AHJ where this "1962 residence" was built.

KWillis, what you describe sounds like the last edition BEFORE the 1962 NEC, where there was a list of the dwelling receptacle locations that were required to grounding type. As for the method of a separate bare EGC with barrel crimp spliced extensions as needed. . . well, that is just another possible way to "skin the cat". Compared to some of the other "solutions" to having an EGC, what you describe seems rather reasonable and effective.
 

480sparky

Senior Member
Location
Iowegia
Starting in 1947, a reduced EGC was allowed only if it was included in the cable assembly.

The 1968 NEC first required a full-size EGC.
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
Starting in 1947, a reduced EGC was allowed only if it was included in the cable assembly.

The 1968 NEC first required a full-size EGC.

That's interesting Ken. Thanks !

I'd have loved to have been in the room when the code making panel developed that one.
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
And I wonder what constitues a cable assembly. Being a bundle of wires under the same staple?

There is a definition of "cable", as used in the NEC, published in the 2016 NFPA Glossary of Terms that says a cable is "A factory assembly of two or more conductors having an overall covering."

So, no, that field assembly you describe in the OP isn't a cable.

You can Google NFPA Glossary of Terms to read a copy.
 

KWillis

Member
Location
San Jose, Calif.
Occupation
Electrical Engineer, Handyman
What you described is very typical for that time period- only recs in certain areas (like the areas you mentioned) were required to be grounded. One old NEC rule was that metal boxes within x number of feet of grounded objects (plumbing) were to be grounded- you'll see grounded boxes/ recs in old kitchens near the sink, but the ones near the dinner table across the room won't be.

They would also bond the metal shell light fixtures in those areas by running that separate egc beside the 2w nm to the ceiling box- very common to see the light and even the light switch box in an old bath grounded thru an egc snaked thru the wall and clamped to the old galvanized plumbing.

FWIW, the separate egc method is still sort of permitted- see 250.130(C)

Yup, the egc connects to an abandoned ceiling box for the kitchen light and the porch light. Thank you for the the history lesson!

The egc gets connected back to the service panel via a copper plated strap to the copper water pipe in the kitchen, then to a solid 6 awg conductor pipe clamped near the garden hose bib. Or I should say it did. During a service upgrade it appears this was disconnected in favor of a ufer ground available from new pool construction and a new gec. Also the EMTs for range and dryer were cut and segments of liquidtight were used to interface with the new panel. And there was no bonding around the liquidtight. Hey, old EGCs need love too!
This was done by a licensed contractor that proudly put their sticker on the panel door :happysad:
 

user 100

Senior Member
Location
texas
Yup, the egc connects to an abandoned ceiling box for the kitchen light and the porch light. Thank you for the the history lesson!

The egc gets connected back to the service panel via a copper plated strap to the copper water pipe in the kitchen, then to a solid 6 awg conductor pipe clamped near the garden hose bib. Or I should say it did. During a service upgrade it appears this was disconnected in favor of a ufer ground available from new pool construction and a new gec. Also the EMTs for range and dryer were cut and segments of liquidtight were used to interface with the new panel. And there was no bonding around the liquidtight. Hey, old EGCs need love too!
This was done by a licensed contractor that proudly put their sticker on the panel door :happysad:

And you have found one of the 2 main pitfalls when this method found its path to the source thru the pipes instead of going to the panel. The other is when plastic replaces that ancient pipe......

Regarding the disconnected #6- if there is still 10ft of the old metal pipe in the ground, it needs to be reconnected, as the old pipe would qualify to be used as an electrode. And whatever the status of that pipe in the ground, the pipe in the house needs to be bonded to the panel anyway- See 250.52(A)(1) and 250.104(B)(1-5)

And as far as the potential for the pipe being replaced, meaning the recs in those areas you mentioned would lose their egcs-go ahead and up those recs that rely on the separate egc to gfci- (they prolly already are considering the locations, but if not.....) and/or talk to the customer about pulling new ckts for those locations and disconnect the old egc or tie it into the egc from a new ckt-prolly need add'l ckts for those areas anyway with the age of the house.
 
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