GEC entering panel

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Please rebut the following argument:

2014 250.64(E)(1) says in part "Ferrous metal raceways and enclosures shall be bonded at each end of the raceway or enclosure to the grounding electrode or grounding electrode conductor." If the grounding electrode conductor is not enclosed in a raceway, this reduces to the statement "Ferrous metal enclosures shall be bonded at each end of the enclosure to the grounding electrode or grounding electrode conductor." The phrase "each end of the enclosure" would include where the grounding electrode conductor exits the enclosure.

Cheers, Wayne
 
They added the parallel path wording that Roger mentioned in the 2017 NEC.

250.64(E) Raceways and Enclosures for Grounding Electrode Conductors.(1) General. Ferrous metal raceways and enclosures for grounding electrode conductors shall be electrically continuous from the point of attachment to cabinets or equipment to the grounding electrode and shall be securely fastened to the ground clamp or fitting. Ferrous metal raceways and enclosures shall be bonded at each end of the raceway or enclosure to the grounding electrode or grounding electrode conductor to create an electrically parallel path. Nonferrous metal raceways and enclosures shall not be required to be electrically continuous.
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250.64 Grounding Electrode Conductor Installation.
Grounding electrode conductors at the service, at each building or structure where supplied by a feeder(s) or branch circuit(s), or at a separately derived system shall be installed as specified in 250.64(A) through (F).

(E) Raceways and Enclosures for Grounding ElectrodeConductors.

(1) General. Ferrous metal raceways and enclosures for grounding electrode conductors shall be electrically continuous from the point of attachment to cabinets or equipment to the grounding electrode and shall be securely fastened to the ground clamp or fitting. Ferrous metal raceways and enclosures shall be bonded at each end of the raceway or enclosure to the grounding electrode or grounding electrode conductor. Nonferrous metal raceways and enclosures shall not be required to be electrically continuous.

(2) Methods. Bonding shall be in compliance with 250.92(B) and ensured by one of the methods in 250.92(B)(2) through (B)(4).

(3) Size. The bonding jumper for a grounding electrode conductor raceway or cable armor shall be the same size as, or larger than, the enclosed grounding electrode conductor.

(4) Wiring Methods. If a raceway is used as protection for a grounding electrode conductor, the installation shall comply with the requirements of the appropriate raceway article.


The enclosure that houses the panelboard is a "cabinet". I think what they are referring to there besides raceways is any other ferrous material that "encloses" the GEC that can act as a "choke" should the conductor be carrying current.
 
In a typical residential panelboard, the GEC enters via the 1/4" knockout, travels about 6" or so and terminates onto the grounding/neutral bar. I fail to see how this is an NEC violation.
 
The additional 2017 wording is helpful.

If a GEC enters through a small knockout and then terminates at a lug which is bonded to the enclosure, then an additional bond at the knockout surely is unnecessary by any electrical theory consideration.

Inspectors I've had this conversation with generally say 'either bring it through a small hole with no connector, or if you put a metal connector on it then you need a bonding bushing on the connector.' I guess once you put that connector on it you've got another 'end' of the metal path to bond. Whereas with just the hole, you've already bonded the only piece of metal along the path.

I've never seen a Kenny clamp in my life.
 
jaggedben said:
The additional 2017 wording is helpful.

If a GEC enters through a small knockout and then terminates at a lug which is bonded to the enclosure, then an additional bond at the knockout surely is unnecessary by any electrical theory consideration.

Inspectors I've had this conversation with generally say 'either bring it through a small hole with no connector, or if you put a metal connector on it then you need a bonding bushing on the connector.' I guess once you put that connector on it you've got another 'end' of the metal path to bond. Whereas with just the hole, you've already bonded the only piece of metal along the path.

I've never seen a Kenny clamp in my life.
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If you put it through a metal "romex clamp" and tighten the clamp IMO you have same thing as a Kenny clamp, though probably never tested/listed for this application.

Hole through the panel is three dimensional just like a tube leaving the panel, just is only 1/16th inch or even less in length.

From a theory perspective IMO as long as a metal raceway containing a GEC is bonded to the service entrance enclosure via locknuts, EMT fitting, etc. it is bonded well enough on that end - the cabinet and raceway kind of become one closure for the conductor, now all you need to do is bond the other end. But how far away does the other end need to be before such bonding is necessary? 1/16 inch cabinet wall thickness, 1/2 inch, 4 inches, 24 inches....?
 
jaggedben said:
Inspectors I've had this conversation with generally say 'either bring it through a small hole with no connector, or if you put a metal connector on it then you need a bonding bushing on the connector.' I guess once you put that connector on it you've got another 'end' of the metal path to bond. Whereas with just the hole, you've already bonded the only piece of metal along the path.

I've never seen a Kenny clamp in my life.
Click to expand...

I've seen this and think that it's dumb. The squeeze connector isn't listed for that in the first place.
 
312.5 Cabinets, Cutout Boxes, and Meter Socket Enclosures.
Conductors entering enclosures within the scope of this article
shall be protected from abrasion and shall comply with
312.5(A) through (C)

(A) Openings to Be Closed. Openings through which
conductors enter shall be closed in an approved manner
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<<<<&&&>>>>
110.3(B) Installation and Use. Listed or labeled equipment shall be
installed and used in accordance with any instructions included
in the listing or labeling
Click to expand...
.

~RJ~
 
So you are saying that the GEC entering the small 1/4" KO is not closed in an approved manner?

Or am I misreading the reason you stated a Code section with no accompanying commentary?
 
I can forward plenty of commentary , some via manufacturers query

At this time i would simply like this to be recognized as a valid concern

thx

~RJ~
 
From: Romex Jockey Electric
Sent: Monday, December 18, 2017 4:10 PM
To: Rick Holbrook Milbank rep
Subject: Technical Question for you



Dear Rick & Cathy Holbrook
I'm a Vermont electrician with a question about Milbank meters and/or enclosures I'm hoping you can help me with.

It would appear there is a dispute in just what the 1/4" knockouts on the bottom of your meters are really for

Some say it's for the GEC (Grounding Electrode conductor)* , usually a bare #6 or #4 copper wire to simply run through

However, we are finding this is not to code, the* NEC passage(s) below being applicable

Can you unfuzz me please? Thank you for your time
~*Vermont Electrician

From: Rick Holbrook
Sent: Tuesday, December 19, 2017 2:04 PM
Subject: FW: Technical Question for you


Hi Steve,
The ¼” KO’s are for water drainage only.
 
The small holes are there for a reason, to bring the GEC into the panel, no connector, no Kenny clamp required. It's as simple as that according to the NEC. For years we used a simple NM 2-screw squeeze connector in a 1/2" KO. Not required but gives more options for KO's. Is it a technical violation because the connector isn't listed for single conductors, yes but who cares, how is that any less safe than running it through the small hole?
 
romex jockey said:
From: Romex Jockey Electric
Sent: Monday, December 18, 2017 4:10 PM
To: Rick Holbrook Milbank rep
Subject: Technical Question for you



Dear Rick & Cathy Holbrook
I'm a Vermont electrician with a question about Milbank meters and/or enclosures I'm hoping you can help me with.

It would appear there is a dispute in just what the 1/4" knockouts on the bottom of your meters are really for

Some say it's for the GEC (Grounding Electrode conductor)* , usually a bare #6 or #4 copper wire to simply run through

However, we are finding this is not to code, the* NEC passage(s) below being applicable

Can you unfuzz me please? Thank you for your time
~*Vermont Electrician

From: Rick Holbrook
Sent: Tuesday, December 19, 2017 2:04 PM
Subject: FW: Technical Question for you


Hi Steve,
The ¼” KO’s are for water drainage only.
Click to expand...

Isn't this thread about panels? From the OP:

[h=2]GEC entering panel[/h]
Click to expand...
 
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