GFI and 3 prong receptacles

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Greg1707

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When did the NEC first require 3 prong grounded receptacles? When did the NEC first require GFI receptacles?
 
A few days ago, I was watching a "OLD" "OLD" episode of Andy Griffith, and noticed a 3 wire outlet on the wall....
 
I am guessing

I am guessing

I am guessing!​

The grounding wire was required in the early 1960s and was only required to be 16 AWG. After some jack-legs tried to use it for a third wire in a cable that started fires, the grounding wire was increase to match the ungrounded conductors through 10 AWG.

The GFCI was required for bathrooms (swimming pools too?) only around 1975 and has expanded its use after that date. :)
 
The first NEC with the words "shall be of the grounding type" appearing in 210.7 is the 1975. Prior to that, grounded receps were allowed and must be properly grounded, but were not required.
 
480sparky said:
The first NEC with the words "shall be of the grounding type" appearing in 210.7 is the 1975. Prior to that, grounded receps were allowed and must be properly grounded, but were not required.
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Ken, check the wording in the 47 concerning "laundry receptacles", it may even go back earlier than that.

Roger
 
Even tho, at one time, cables all had ground wires throughout the house the grounded recep. were only install in the kitchen areas
 
roger said:
Try 2124

Roger
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OK, that's one exception. And I can't find it in the '40, or '43 supplement.

chris kennedy said:
How did you get a copy of the 2124 NEC?
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Roger's real name is Emmet Brown.... Here he is with an illustration from the 2124 NEC:

flux-capacitor-schematic.jpg


(Photo taken in 1955).

Actually, he's referring to Article 2124 of the 1947 NEC.
 
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Dennis Alwon said:
Even tho, at one time, cables all had ground wires throughout the house the grounded recep. were only install in the kitchen areas
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And at a time slightly before that, the home run and circuit cables that fed kitchen and bath outlets close to sinks and such contained an EGC, and then non-EGC cable was used beyond those points.
 
charlie said:
I am guessing!​

The grounding wire was required in the early 1960s and was only required to be 16 AWG. After some jack-legs tried to use it for a third wire in a cable that started fires, the grounding wire was increase to match the ungrounded conductors through 10 AWG.
Click to expand...
I am not an electrician (engineer), but was a hack at it in the '60's as a kid. Daddy had a house built in 1961/1962; I wanted a ground run to my room where I did ham radio and other electronics, etc. The electrician told daddy that they were only required on our 1st floor (because we had a brick floor on a slab) but he would satisfy his son's request. I don't know if the requirement really existed, but he wired the ground level with 14-2WG. The ground was smaller. I don't remember any 20A branch circuits. Lighting panel was fuses, service panel was breakers. We had electric resistance ceiling heat ... lots of breakers for that, each room unique.

My wife and I owned a house built in 1972 with 2-wire-no-ECG 15A and 20A branch circuits.
 
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I believe the current style of 3 prong plug and receptacle became available about the early to mid 1950s. Amphenol made these to fit a standard octal socket hole and some mounted with the same kind of snap ring as some octal sockets. The equipment mounted plug on the rear of the equipment was identical to the plug on the end of a cord that mated with the wall receptacle. Cords made in this manner could be cascaded together.

Some history from:
http://www.absoluteastronomy.com/topics/Domestic_AC_power_plugs_and_sockets
The three prong plug was invented by Philip F. Labre, while he was attending the Milwaukee School of EngineeringMilwaukee School of Engineering

The Milwaukee School of Engineering is a private university located in downtown Milwaukee, Wisconsin....
(MSOE). It is said that his landlady had a cat which would knock over her fan when it came in the window. When she plugged the fan back in, she would get an electric shockElectric shock

An electric shock can occur upon contact of a human or animal body with any source of voltage high enough to cause sufficien...
. Labre figured out that if the plug were grounded, the electricity would go to earth through the plug rather than his landlady. He applied for and was issued a patent for grounding receptacle and plug on June 5, 1928.
Click to expand...

.
 
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