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Where Equipment Grounding Conductor Is Not Provided

Where Equipment Grounding Conductor Is Not Provided

New postby Marc M on Fri Nov 30, 2012 2:13 pm

Hey Jerry,
can you tell me, in the situation (attached), in a separate building, where a EGC is not provided, can under those explained circumstances, the neutral to case connection be acceptable? Or is it always NEVER?
I'm just wondering how come a 3 wire service to a remote is allowed (if no metallic connections exist) and if the remote panels G terminal is bondedto the case, wont that return back to the main service panel? I thought we were tring to separate the two panels?

Also, can you double check my terminology please?
GES - grounding electrode system: it encompasses the electrode as well as the conducor
EGC - Equipment grounding conductor: it is the conductor that connects the mai service panel ground ( ground/grounding/grounded?) system to the ( ground/grounding/grounded?) remote panel ground system
GEC - Grounding electrode conductor: Connects the ground ( ground/grounding/grounded?) to the electrode

In a remote panel; where a separate grounding electrode is required; is the connecting conductor still referred to as the GEC or is it referred to as EGC?
Is the term EGC used to describe the conductor used to facilitate all connections of components in equpotential bonding?

Perhaps you have the ability to make a drawing of the anatomy of a remote panel using the correct terms?

Thanks for bearing with these questions, just trying to look less like a fool with my terms. I ask electricians that I know these same questions, they just look at me with a blank stare, the lot of them.
Marc
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Re: Where Equipment Grounding Conductor Is Not Provided

New postby Marc M on Fri Nov 30, 2012 10:18 pm

Okay, take alook at these illustration also. They show a 3 wire system (2nd two) where the panel is bonded to the neutral bus which establishes an effective ground fault path.
The first is what you typically think as okay because the neutral bus is isolated from the case. And has a G-rod as a path source to ground. IS this incorrect because the earth is not an effective source of ground?
So many different rules, but need to get this right..
Thanks
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Re: Where Equipment Grounding Conductor Is Not Provided

New postby Jerry Peck - Codeman on Wed Dec 05, 2012 8:30 pm

Marc,

My apologies for my delay in answering, I've been busy with several litigation cases which have been consuming most of my 'spare' time recently.

I'll start at the top of your post and work toward the bottom of it.

can you tell me, in the situation (attached), in a separate building, where a EGC is not provided, can under those explained circumstances, the neutral to case connection be acceptable? Or is it always NEVER?


The answer at the time that article was written was 'yes, under some specific circumstances' as that article was written 'back when that was allowed': January 27, 2004 | IAEI January-February 2004

That was allowed in the 2005 NEC but was hanged in the 2008 NEC and is no longer allowed, except that existing buildings so wired are allowed to remain wired that way.

Now, though, the only exception is for existing buildings with existing installations as described, not newer installations.

I'm just wondering how come a 3 wire service to a remote is allowed (if no metallic connections exist) and if the remote panels G terminal is bonded to the case, wont that return back to the main service panel? I thought we were tring to separate the two panels?


It is no longer allowed, and, yes, you are correct in that we are trying to separate the neutral conductor (grounded conductor) and the grounding conductor (in this case the equipment grounding conductor) from each ... not that we are trying to separate the two panels.

The intent is to remove any neutral current from taking the grounding conductor, or earth ground, back to the other building.

GES - grounding electrode system: it encompasses the electrode as well as the conducor


Almost correct. The "grounding electrode system" includes all the grounding electrodes, and all of the grounding electrodes which are present are required to be bonded together, so the grounding electrode bonding conductor would be part of the "grounding electrode system".

The "grounding electrode conductor" is separate from the "grounding electrode system".

EGC - Equipment grounding conductor: it is the conductor that connects the mai service panel ground ( ground/grounding/grounded?) system to the ( ground/grounding/grounded?) remote panel ground system


Correct as far as your statement takes it ... the "equipment grounding conductor" is the conductor which connects the main service panel ground to all the other parts of the system which are to be connected to ground for carrying fault current (unintended current) versus carrying intended current (such as is on the grounded neutral conductor and the ungrounded 'hot' conductors), and the remote panel enclosure is one of those parts which is required to be grounded by the equipment grounding conductor, its just that the equipment grounding conductor is 'not just for' grounding the remote panel enclosure.

GEC - Grounding electrode conductor: Connects the ground ( ground/grounding/grounded?) to the electrode


Yes, but to word it differently, the "grounding electrode conductor" is the conductor which connects the "grounding electrode system" (see above) to the service equipment enclosure and becomes the point to which the neutral conductor is bonded to ground at.

In a remote panel; where a separate grounding electrode is required; is the connecting conductor still referred to as the GEC or is it referred to as EGC?


A "grounding electrode system" is required at the remote panel on a separate building (not sure you are still referring to the remote panel being on a separate building or just being a remote panel in the same building), and there will be "grounding electrode conductor" which connects the enclosure of that remote panel in that separate building to the "grounding electrode system". That "grounding electrode conductor" is different than the "equipment grounding conductor".

Is the term EGC used to describe the conductor used to facilitate all connections of components in equpotential bonding?


No, the conductor for equipotential bonding is a "bonding conductor" as it "bonds" the various items together but "does not ground" those items.

Perhaps you have the ability to make a drawing of the anatomy of a remote panel using the correct terms?


Not where I am now or on this computer.

I ask electricians that I know these same questions, they just look at me with a blank stare, the lot of them.


Possibly because they do not know the names of the different conductors, and possibly because some of your terms are intermixed, although I suspect it is more likely the former rather than the latter.

Is the above a good start on answering your questions>
Jerry Peck - CodeMan
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Re: Where Equipment Grounding Conductor Is Not Provided

New postby Marc M on Wed Dec 05, 2012 9:07 pm

Good stuff Jerry. I appreciate you taking your time.
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