# GEC exit from service equipment



## MDShunk (Jan 7, 2007)

I know that 99% of guys will take their grounding electrode conductors out of the service panel or meter stack out of one of those little 1/4" knockouts. After all, that's what they're for, right? It seems in recent years, there's a fitting called the "Kenny Clamp" that people are starting to use to exit their panels, meter stacks, and CT cans. In the first picture below is a normal typical set of GEC's exiting a meter stack through a 3/8" two screw NM connector. The second picture is a CT can I did a couple of months ago where I decided try out the Kenny Clamp. It does make for a nice, finished appearance.


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## Speedy Petey (Jan 10, 2007)

How much do _those_ things cost?

Although I have never worked with it, it looks a bit like an MI cable connector.


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## MDShunk (Jan 7, 2007)

Speedy Petey said:


> How much do _those_ things cost?
> 
> Although I have never worked with it, it looks a bit like an MI cable connector.


Yes, they do put you in mind of a gland connector for mineral insulated cable. I've only worked with that stuff twice in my life for a generator hookup. 

The Kenny Clamp connectors are 4 bucks a piece. They were invented by an inspector in Prince George's County, Maryland, from what I understand. They are being made by M&W. I use a lot of M&W stuff for services. They're a good old-time brand. I use their service cable straps and their weatherheads. I used to use their weatherproof SE connectors, but I can't buy them around here now. 

Here's a link to the Kenny Clamp: http://www.mwelectricmfg.com/NewAdditions.html


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## 3phase (Jan 16, 2007)

My inspector requies the GEC exit the panel in conduit. If it is metal conduit then the bonding bushing is required but not on PVC. He would probably have a purple kitten if I tried one of the fittings then I have to trip over the kitten the rest of the day!


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## Joe Momma (Jan 23, 2007)

3phase said:


> My inspector requies the GEC exit the panel in conduit. If it is metal conduit then the bonding bushing is required but not on PVC. He would probably have a purple kitten if I tried one of the fittings then I have to trip over the kitten the rest of the day!


 
That's funny.

We usually use PVC too, to avoid the extra fitting for steel conduit. Those Kenny clamps look good to always keep the same potential between the GEC and cabinet(I wonder how a romex connector rates for carrying current)

The reason for the fitting on the steel pipe is because the magnetic field created from the conductor carrying a lightining strike would impose an opposite field on the conductor carrying the current, thusly stopping all current flow.

I know with parallel conductors it is allowed to carry all of each phase in each pipe, although the entrance of each pipe would need to be cut in between(slits in the can) to keep the fields of each pipe from creating a resistance to itself. Now this strikes a question of when we run the GEC in PVC but it comes through the steel can, wouldn't that ring of steel where the pipe enters also create this CEMF field around the conductor?


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## MDShunk (Jan 7, 2007)

Joe Momma said:


> Now this strikes a question of when we run the GEC in PVC but it comes through the steel can, wouldn't that ring of steel where the pipe enters also create this CEMF field around the conductor?


I'm betting it might... but consider this... that GEC is connected to some lug in that can. Perhaps the can and the GEC are already at the same potential because of this? So far, nobody in the industry seem to be raising any red flags about that question, but I have privately wondered the same thing. I mostly used those Kenny clamps for a more finished appearance. I sorta thought they dressed up the install a bit. If they happen to also enhance the performance of the grounding electrode system as a side benefit, then that's a bonus.


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## raider1 (Jan 22, 2007)

> My inspector requies the GEC exit the panel in conduit.


Is it subject to physical damage? Typically unless the GEC is subject to physical damage or smaller then a #8 AWG they aren't required to be installed in a raceway. (See 250.64(B))

Chris


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## Joe Momma (Jan 23, 2007)

I don't see a definition for "physical damage", I would imagine that's where the issue comes to play. 
I don't know how the connection to the electrode could be protected from physical damage. I mean how often is the top of a ground rod inside a box?


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## raider1 (Jan 22, 2007)

Joe Momma said:


> I don't see a definition for "physical damage", I would imagine that's where the issue comes to play.
> I don't know how the connection to the electrode could be protected from physical damage. I mean how often is the top of a ground rod inside a box?


Joe, it seems here in Utah most everone installs the GEC in a PVC conduit because that just the way we have all ways done it. My point was if an inspector was to say that I was required to install the GEC in a conduit I would like to see why he thought the GEC was subject to physical damage.

P.S. Overcurrent devices can not be installed where subject to physical damage so if the GEC at the service disconnecting means is subject to physical damage wouldn't the overcurrent device also be subject to physical damage?

Chris


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## MDShunk (Jan 7, 2007)

It's interesting that people sometimes sleeve the exposed GEC in a bit of PVC conduit. Schedule 40, no doubt. In the eyes of the code, schedule 40 is the same as nothing at all. Schedule 40 PVC is not rated for protection against physical damage.


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## JohnJ0906 (Jan 22, 2007)

Somewhere I had thought I had heard that we shouldn't use those 1/4" KOs for the GEC because in the event of a lightning strike it would arc at that point, possibly damaging or severing the wire at that point. Sorry, that seems to be emerging from the back recesses of what passes for my memory:whistling2:


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## raider1 (Jan 22, 2007)

MDShunk said:


> It's interesting that people sometimes sleeve the exposed GEC in a bit of PVC conduit. Schedule 40, no doubt. In the eyes of the code, schedule 40 is the same as nothing at all. Schedule 40 PVC is not rated for protection against physical damage.


Agreed, I see this all the time. I think it boils down to the old addage "Thats how we have always done it." even though it is not required.

Chris


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## MDShunk (Jan 7, 2007)

In fairness, I sometimes sleeve the grounding electrode conductor when the mood strikes me. I do this for no other reason than to simply "pretty up" the install. On certain installs, the exposed GEC aestitically just seems wrong. I can't put my finger on why or how. I have used RMC to sleeve the GEC when I knew it needed physical protection.


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## Joe Momma (Jan 23, 2007)

raider1 said:


> Agreed, I see this all the time. I think it boils down to the old addage "Thats how we have always done it." even though it is not required.
> 
> Chris


I don't think it boils down to "how we've always done it", I'm pretty sure we just don't like running a piece of wire up the wall and saying we did that. We would honestly run it in EMT if it didn't require the special fittings, if we did it that way we could even do some pretty bends and do it up right.


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## round2it (Jan 22, 2007)

Raider, your little figure bouncing was going right in time with the song I was listening to...cracked me up...oh yeh, that simple mind showing itself again...sorry for being off topic.


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## raider1 (Jan 22, 2007)

> Raider, your little figure bouncing was going right in time with the song I was listening to


Was it a Pantera song? Thats what I usually listen to while surfing the electrical sites:thumbup: 



> I don't think it boils down to "how we've always done it", I'm pretty sure we just don't like running a piece of wire up the wall and saying we did that. We would honestly run it in EMT if it didn't require the special fittings, if we did it that way we could even do some pretty bends and do it up right.


I agree that I personally install a GEC in PVC to clean it up and make it look good. I was thinking more about the electricians that tell me that you HAVE TO install a GEC in a PVC conduit. When I ask them why, they tell me cause it's somewhere in the code, and besides thats how we have always done it.

Chris


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## round2it (Jan 22, 2007)

I am all for the neater install. It doesn't take that much and when you want to distinguish yourself from the competition, you do the little extra things like that. At least that is the way I look at it. Also when someone tells me "its somewhere in the code" I say, "Really...show me!!!" 

No Chris it wasn't a Pantera song...I think I was listening to Floyd...they are my faves

Matter of fact...listening to Another Brick in the Wall as I type...


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## 3phase (Jan 16, 2007)

Raider, it is his "thing". I try not to argue with inspectors unless they are off base, it just makes life so much easier. Besides PVC is cheap and it does look better than a wire running down the house to me.


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## raider1 (Jan 22, 2007)

3phase said:


> Raider, it is his "thing". I try not to argue with inspectors unless they are off base, it just makes life so much easier. Besides PVC is cheap and it does look better than a wire running down the house to me.


It is funny how some inspectors have certain quirks like requiring a GEC to be installed in a schedule 40 PVC conduit when schedule 40 can't be used for protection of a GEC. Other inspectors only look for staples and nail plates but totally ignore other violations.

I agree that PVC makes the installation look good and I have almost always installed my GEC's that way, my problem comes when an inspector requires it.

Chris


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## TheElectricalGuru (Jan 16, 2007)

We simply use the 1/4" hole provided by the manufacturer, ensure our connection in the enclosure and run it along the wall, strapped nice and yep....exposed.


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## acrwc10 (Jan 28, 2007)

MDShunk said:


> It's interesting that people sometimes sleeve the exposed GEC in a bit of PVC conduit. Schedule 40, no doubt. In the eyes of the code, schedule 40 is the same as nothing at all. Schedule 40 PVC is not rated for protection against physical damage.


 
Afew years ago I had to run a ground loop for a telcom sight to a ground ring in 750 mcm , The engineers wanted it in pvc with pvc straps. They said the metal strap created a "choke" in the ground circuit. I had to take a moment to myself to laugh because they said nothing about all the other metal items the pvc ran through like metal studs in the walls, rebar in the wall it exited the building through, etc. 
On the subject of physical damage that seems to be a subjective term with no uniform definition.Just don't tell the ahj in my area that sch 40 isn't good enough, I would rather just keep using it when needed.


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