Question to Mr. Holt or ??

[celtic]

IMO there is no NEC need for that 'Kenny Clamp'.

Here are some different opinions:
Factory KO Question

Notched hole for GEC

GEC entering panel

 

[roger]

IMO there is no NEC need for that 'Kenny Clamp'.

Run the EGC through a hole and bond it to the enclosure by other means. (As in the neutral bar)

I agree, how many times does the GEC need to be bonded enclosure?

Roger

 

[tom baker]

Do you mean a GEC, or the wire to the ground rod?
If so, its a Kenny Clamp.
Mike and I were at the IAEI conference in Orlando some years ago where we saw the Kenny Clamp at mfgs booth. The manufacturer is 100% correct in saying that a romex clamp or hole in a service can violates the NEC.
I purchased some of the Kenny Clamps, about $3.50 each.
urlhttp://www.mwelectricmfg.com/NewAdditions.htmlurl
strip off the URL and paste into your browser.

 

[George Stolz]

The manufacturer is 100% correct in saying that a romex clamp or hole in a service can violates the NEC.

Reference?

 

[iwire]

The manufacturer is 100% correct in saying that a romex clamp or hole in a service can violates the NEC.

What section would that be?

 

[George Stolz]

Jinx! .................

 

[ryan_618]

I think it could be argued that 312.5(A) requires the connector. What do you guys think?

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 adequately closed.

 

[Dennis Alwon]

I think it could be argued that 312.5(A) requires the connector. What do you guys think?

What does adequately closed mean???? A #6 wire through a 1/4" hole is pretty well closed. What's left is a lot less than a weep hole that is in a meter base.

 

[tom baker]

Here is the mfgs statement on code sections:
"Complies with 110.3(B) and 250.8 NEC, using a listed grounding or bonding connector for the proper application.

Complies with 250.64 (E) NEC when entering and exiting metallic raceways and enclosures."

At the IAEI meeting, where the mfg had the product booth, I was there with Mike Holt and Phil Simmons. Phil was the chair of CMP 5 (Art 250) for several cycles and the author of Soares Book on Grounding, he was also an electrical inspector in Washington State. I asked him if he would require someone to use the product, and he said no as they are the only mfg. But both he and Mike saw the correctness of the product, which is why you see it in all Mikes graphics.
I have some samples I tote around for my classes.

 

[LarryFine]

Here is the mfgs statement on code sections:
"Complies with 110.3(B) and 250.8 NEC, using a listed grounding or bonding connector for the proper application.

Complies with 250.64 (E) NEC when entering and exiting metallic raceways and enclosures."

Saying that use of a device complies with code is a far cry from saying that not using the device is non-compliant.

 

[iwire]

Saying that use of a device complies with code is a far cry from saying that not using the device is non-compliant.

I agree.

I see no actual 'need' for this product but it sure does look pretty and I am sure it cost enough to make the manufacturer very happy if they could get inspectors to require it.

 

[George Stolz]

I haven't seen services that have been subjected to abuse that would prove the need for this clamp. I can imagine that the flashover from the GEC to the can as it passes through a small hole could cause some damage.

In the same breath I wonder if it would really help; if the flash in question was barrelling along the GEC in the first place, then chances are some damage to the can on the way by would be the least of the issues.

I'll have to look and see what the max size of these things are, too. I've run insulated 1/0 AL GEC's into the back of a can before, I wonder if they've designed these with larger GEC's in mind?

 

[tom baker]

I haven't seen services that have been subjected to abuse that would prove the need for this clamp. I can imagine that the flashover from the GEC to the can as it passes through a small hole could cause some damage.

I just remembered that one of my students saw a video of a test on the Kenny Clamp and with out it. I'll see if I can get more info. They owe me as I am the only person on the West coast using!

 

[celtic]

Roger:
Round & round I go. The link page has a pic of Mike (& Steve) and the next link takes you back to the main forum page.

PS, it's quitting time at office....1-1/2 hr ride home, be back later.

John

Yesterday, 03:51 PM


I hope that bloke got home "ok".

 

[John Arendt]

OK, yes I got home OK, and my head was spinning from the revolving link.

It's been a busy Sat. & I did not get back here till Sat PM, and I have read all the responses.

Basically, Mike & Phil saw the Kenny Clamp.....like the intent, saw the 'need', put it in the graphics, but....Phil does not require it, as there is only one mfg. of the clamp.

References were made to 110.3 (B); 250.8; 250.64 (E) and 312.5 (A).

Opinions range from 'I'm the only one who uses it' to 'not necessary'. No individuals mentioned, no quotes.

Here in my area, it has been common practice over the years to use a two screw NMC connector, or recently the black button push-in NMC connector.
Although based on the 'letters of the laws', no fuss was made regarding the technical mis-use of a 'cable' connector for a 'conductor'. Personally, I have not seen ANY EGC's thru the '1/4-5/16" hole in panels.

Iwire: (Bob)
Quote:
Originally Posted by tom baker
The manufacturer is 100% correct in saying that a romex clamp or hole in a service can violates the NEC.

What section would that be?

Not speaking for Tom, and based on the responses within this thread, and my opinion:

As the NMC connector is intended for a 'cable'; technically, it should not be used to secure 'cord' or 'conductors', or anything other than 'cable', and NMC specifically.

The 'hole' argument goes back to 312.5 (A), and lack of any connector securing said conductor to the enclosure.
Please don't take this reply as a flame attempt, or some smart aXX attempting to fan flames, or drag on what some may consider a stupid subject. This debate/subject has been kicking around for 2+ weeks b'twn an AHJ and EC and ALL I'm seeking is opinions and input, and hopefully an NEC reference or two.

The vast array of experience and knowledge available on the trade forums is appreciated, and I intend to offend no one.

John

 

[electricmanscott]

$3.50 For a connector in this application is outrageous. A standard romex connector is more than enough for this application. While not "technically" correct installation it certainly should be.

 

[George Stolz]

John, welcome to the forum.

Personally, I have not seen ANY EGC's thru the '1/4-5/16" hole in panels.

One cool thing about this site is, since it is a national forum, we get exposed to different 'standards' of installation quite a bit. For example, a typical North-East-Coast service would never pass in my area of CO, simply because it looks so different than what we're used to seeing.

Around here, a #6 GEC running from a ground rod through a hole in the bottom is routine.

The manufacturer is 100% correct in saying that a romex clamp or hole in a service can violates the NEC.

What section would that be?

The 'hole' argument goes back to 312.5 (A)...

I would tend to disagree with that. A #6 bare fills a 1/4" hole in the bottom of the disconnect quite completely, IMO. I would venture to guess that the amount of daylight visible through the hole would be less than you'd see through a two-screw NM connector in a 1/2" hole.

)...and lack of any connector securing said conductor to the enclosure.

I think this gets down to where the rubber meets the road on this issue: Where is it required that any single conductor be secured to the box? I don't see a requirement for single conductors, or more specifically, for a GEC to be secured to the box.

Look at this from another perspective: if the GEC were piped out of the box in Sch 80, down the wall, and ended at grade, would we instinctively feel like securing the GEC to the box?

As the NMC connector is intended for a 'cable'; technically, it should not be used to secure 'cord' or 'conductors', or anything other than 'cable', and NMC specifically.

Agreed. 110.3(B) could be cited for misusing the connector, IMO.

In fact, due to this technicality being brought up in a review of my shoddy work, I personally switched to just a hole.

Please don't take this reply as a flame attempt, or some smart aXX attempting to fan flames, or drag on what some may consider a stupid subject.

I don't consider this a stupid subject at all, and I hope nobody takes my responses to be negative either.

 

[mike@mikeholt.com]

Just Mike Holt

Just Mike Holt

The NEC does not require a connector on the GEC when it leaves an enclosure. Sometimes in our graphics we use a Kenny Connector and other times we just run the GEC through the enclosure without a connector.

Our office staff contacted Square D and UL and the response is that the 1/4' knock out in equipment is specifically for the use of the grounding electrode conductor without a connector.

My office will be making a proposal for the 2011 NEC to clarify this issue.

 

[George Stolz]

$3.50 For a connector in this application is outrageous. A standard romex connector is more than enough for this application. While not "technically" correct installation it certainly should be.

Scott, I agree that an NM connector should be allowed for this.

If four different manufacturers were making the Kenny Clamp, then the price would be lower. I think the Kenny Clamp does make for a neater installation, and demonstrates a nod to workmanship, but I don't think more damage would come from a two-screw NM connector than a Kenny Clamp. But I haven't seen the demo, either.

But both he and Mike saw the correctness of the product, which is why you see it in all Mikes graphics.

Thanks for the explanation, Tom!

 

[George Stolz]

Thanks for dropping in, Mike!

My office will be making a proposal for the 2011 NEC to clarify this issue.

Would you favor proposing the Kenny Clamp for the application, or just clamping the GEC to the box (leaving the door open for a product like a two-screw connector)?