When did the NEC prohibit neutral-to-case connections on the load side.

Douthit

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Utah
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Home Inspector
When did the NEC prohibit neutral-to-case connections on the load side.
We come across old homes that have the neutral-to-case connection after the main on the load side breaker distribution panel as well as the main panel

But I can not find when this practice was discontinued.
 

infinity

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New Jersey
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Journeyman Electrician
I think that you might have to go back 100 years or so. I'm not sure that this was ever permitted.
 

mwm1752

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Location
Aspen, Colo
most likely when the grounded conductor was a bare concentric. There was a time when the EGC wasn't required for a feeder to another structure panel - see NEC 2017 230.32 (B)(1) exception 1 which addresses the specifics which ECG was not required - NEC 2002 230.32 (B)(2)
 

mbrooke

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What?

I'm just saying 200.2(B) was a change to the 2008 NEC. Continuity of the grounded can't be dependent on the enclosure.
Quote from the the NEC of 200.2 (B). But I get what your're saying now, it came after the fact so nothing to quote from prior additions.
 

mwm1752

Senior Member
Location
Aspen, Colo
What?

I'm just saying 200.2(B) was a change to the 2008 NEC. Continuity of the grounded can't be dependent on the enclosure.
I was under the impression 200.2(B) meant you could not tie any grounded conductor to a equipment ground terminal attached to a first disconnect panel frame so that all grounded conductors were attached to the common buss bar which the service grounded conductor was attached. How does that associate with the OP question - Grounded conductor connections to metal case which EGC are connected to after 1st disconnect?
 

chris kennedy

Senior Member
Location
Miami Fla.
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60 yr old tool twisting electrician
I was under the impression 200.2(B) meant you could not tie any grounded conductor to a equipment ground terminal attached to a first disconnect panel frame so that all grounded conductors were attached to the common buss bar which the service grounded conductor was attached. How does that associate with the OP question - Grounded conductor connections to metal case which EGC are connected to after 1st disconnect?
Yup
Completely misread the OP.
Appears OP is asking about 250.142.
 

don_resqcapt19

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Illinois
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retired electrician
But yet that installation is so commonly found that one would think it was compliant.
It is commonly found because a lot of electricians do not understand the code and because they don't want to throw the manufacturer supplied main bonding jumper...the green screw, so they just install it.
 

Clayton79

Member
Location
illinois
Well I guess if everyone is going to throw out an opinion, here is my 2 cents.. since I don’t own a code book older than 1999, I’m guessing probably around the time they started requiring grounded systems in residential installations.. does anyone know when that might have been? I’m just guessing mid sixties maybe?


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darkenergy

Member
Location
Weirton WV 26062
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semi-retired electrician
Poster boy for haste makes waste I am. I had not even heard of the 'NEC style manual' previous to the last couple of years if that is what it is actually called, and if I got the name right, I would be surprised at that. Something to pursue in my spare time, who has it? LOL. I'm going to make time eventually.

I believe I should have stated 250.24 (A) (5) load side grounding connection, First, instead of referring to 'separately derived'.

I can't even remember when I became aware of the 'NEC HANDBOOK' version… Which has 'commentary printed/highlighted blue'.

For instance, the 2017 handbook commentary of the above refers you to 250.142 (B)

As far as the OP's original question… "When did the NEC prohibit neutral-to-case connections on the load side."…

I'm going to see if I still have a copy of the 96 code, maybe even 93 if I did the math right. It was around that time that I started trying to be an electrician instead of just calling myself one. Shocking, I know.

Even then, in my haste and zeal I could not make the distinction between 'grounded conductor' and grounding conductor… Meant the same in my mind.

Not even sure if it was always referred to as the grounded conductor… something else to look up.
 

darkenergy

Member
Location
Weirton WV 26062
Occupation
semi-retired electrician
I put this in the wrong thread, my excuse is I'm new and hasty... my apologies. I'm going to try to copy and past it to where I wanted to go, LOL, wish me luck! Don't know if it's acceptable to delete posts or even how to do it.

A point of clarification if anyone would care to venture one. If the 'grounding electrode conductor' lands on the equipment grounding bus, that is when the appropriately sized wire type jumper is required to the neutral bar. I would still put in the green screw in the neutral bar. Any opinions or statements of fact as far as you know would be much appreciated.

Thank you, Willy
 
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