what year did full sized ground with romex come in

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1968

1968

1968 was the year that the EGC table 250-95 (now 250.122) took the shape that it is in today (except that 300 amps wern't listed). In 1965 15 amp circuits weren't listed, 20 amp circuits were protected by #16 cu if in a cable assembly, 30 amp by #14, 40 amp by #12, and 60 amp by #10.

In 1962, all receptacles on 15 and 20 amp circuits were to be the grounding type 210-21(b). New circuits feeding such needed to provide an grounding conductor 210-7.

In 1959, various locations needed the receptacles to be grounding, but less than all 210-22(b).
 
So what you are saying is that it might have been in use before it was actuallly in the code?

Maybe. The first requirement for a grounding type receptacle came in 1947, for the laundry 2124 b. In 1959 the construction sub-section 336-2 of NM Article allowed for an 'approved size of uninsulated or bare conductor for grounding purposes only'. It was not disallowed before that, AFAIK. AC was typically use for grounding before that, though, or maybe aluminum or lead-sheathed cable, if not a raceway.
 
In 1965 15 amp circuits weren't listed, 20 amp circuits were protected by #16 cu if in a cable assembly, 30 amp by #14, 40 amp by #12, and 60 amp by #10.

Wow. 60A on #10 seems ridiculous. What changed, though? Electrons just didn't decide to run a little hotter in the past 45 years...did they?
 
Wow. 60A on #10 seems ridiculous. What changed, though? Electrons just didn't decide to run a little hotter in the past 45 years...did they?

No, sorry that I was unclear. Just the EGC size fo a 60 amp circuit allowed at that size (#10), same as now. But the smaller amperage OC sizes allowed smaller EGCs than today.
 
I'm not following you. I see 15a circuits with a 16 ground, and 20 & 30s with a 14.

Just responding to
Prior to that, and back through the 1947 NEC, a reduced-size ground was only allowed as part of an approved cable assembly.

Depends on what you/we mean by reduced-size. I was thinking 'compared to today'. So a #14 EGC for a 30 amp OCP branch-circuit is reduced-size, to me. But allowed in earlier cycles whether or not in cable. Only the #16 EGC for a 20 amp circuit needed to be in an approved cable assembly (1959 example, anyway).
 
Just responding to


Depends on what you/we mean by reduced-size. I was thinking 'compared to today'. So a #14 EGC for a 30 amp OCP branch-circuit is reduced-size, to me. But allowed in earlier cycles whether or not in cable. Only the #16 EGC for a 20 amp circuit needed to be in an approved cable assembly (1959 example, anyway).


I'm referring to just NM cable, not all circuits. The asterik (regarding approved cable assemblies) we're referring to shows up first in the '47.
 
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