Approved GEC Bonding Method

[Canton]

Here we see that as a violation of 110.3 and 250.70. There is not much surface contact to that lug or any certainty that it will hold. When dealing with a grounding electrode you wants to be sure it will hold up to its intended purpose.

I will agree with that. When those lugs are listed and tested it is with the intention of all the surface area being in contact. I don't see that.....

 

[iwire]

I will agree with that. When those lugs are listed and tested it is with the intention of all the surface area being in contact. I don't see that.....

It is my opinion you are guessing as it is very common for panelboards with these types of lugs factory installed without 'full contact'.

 

[iwire]

I respectfully disagree. The electrode does not extend 5' from grade, the electrode is underground, however the first 5' entering the structure can be used as a conductor to attach to the electrode. I do agree that meter position does not matter. Question, if we were to just attach on the supply the side of the meter then there would be no need to bond around it, correct? My understanding is that it's always bonded round anyways because that is the easiest spot for bonding the interior metal water pipes.

I don't see 250.52(A)(1) saying that at all.

 

[mjc763]

I don't see 250.52(A)(1) saying that at all.

250.68(c) out of the 2011 code, I don't think it has changed in the 2014 I just don't have that one handy

 

[GoldDigger]

Well seeing as you can't provide a code section and this is a common method in my area and seemingly other areas as well we will have to remain in disagreement.

It just took me awhile, and the statement is indirect, but still IMHO persuasive:

250.70 [2011]:

...Ground clamps shall be listed for the materials of the grounding electrode and the grounding electrode conductor ....

If the ground clamp unit does not directly connect to both the electrode and the wire (conductor), the requirement above cannot be applied.
Now you can argue that the setscrew lug, although not a wire is in fact a conductor, and so the clamp would just have to be approved for the electrode and the lug material. As long as the surface of the clamp which is connected to the lug is the same surface and attachment method which was designed to connect to a wire if that was the mechanical design of the clamp.
I have serious doubts whether the clamp shown on the pipe in the picture is in fact listed as a ground (GEC) clamp. Listing would not be required for a bond clamp.

 

[kwired]

When weg get into o size gec its hard to find the clamp that fits a 4 or 6 " water pipe and the gec termination point be any bigger than awg 1 or 2. I may be mistaken by memory , but I think we put the bolt for tightining the clamp through the lug then through the clamp with lock washer and nut .. on the clamp side that doesnt open. When the crimp tool is there . I have seen it crimped down to 100 a wire size. Although from what is being posted gec s cant be connector to connector.

I have had no trouble getting pipe clamps that accept a 250 kcmil coductor in both 1" and 4" pipe sizes.

 

[kwired]

Simple enough, but without section citations:
A grounding pipe clamp is listed for attaching a GEC to a pipe, not for attaching a lug attached to a GEC to a pipe.
I would guess that since the pipe clamp used does not have a place to attach a wire directly it is not in fact a listed or recognized ground clamp under NEC.
If the pipe clamp does have a wire connection point and you do not use it you are violating the installation instructions.

I am with you on it being more of a listing issue then a NEC issue making the applicable NEC section 110.3(B).

 

[electricalist]

Is that 2 gec s ending at cold water? It might have been better to bldg steel if possible suplemented with ground rod. And if cold water got a green tag see if #6 could be used for cold water since most cw clamps dont accomidate o size. But they can be found. Also gec should never be spliced in any way other than compression.

 

[MannyBurgos]

250.64

 

[electricalist]

I have had no trouble getting pipe clamps that accept a 250 kcmil coductor in both 1" and 4" pipe sizes.

Whoa, what size service is that gec for and how did it end up at cold water over cee or provable bonded to cee bldg steel. . Thats expensive to get to cw sometimes. Im asking seriously I dont undermine anyone.

 

[mjc763]

Is that 2 gec s ending at cold water? It might have been better to bldg steel if possible suplemented with ground rod. And if cold water got a green tag see if #6 could be used for cold water since most cw clamps dont accomidate o size. But they can be found. Also gec should never be spliced in any way other than compression.

Im assuming that is not two GEC but rather one GEC and then a bonding jumper around the water meter.

 

[electricalist]

If we believe the installer ought not have used lugs. I fall on the side of if I have to create something that could easily be made and ul approved then either my method or application is incorrect. Having said that. If he had put the grounds between the clamp and the pipe would he be any better off?

 

[mjc763]

If we believe the installer ought not have used lugs. I fall on the side of if I have to create something that could easily be made and ul approved then either my method or application is incorrect. Having said that. If he had put the grounds between the clamp and the pipe would he be any better off?

I think he would have been better off using two of these ground clamps. He could have ran the wire thru the first clamp unspliced right to the second one.

 

[kwired]

Whoa, what size service is that gec for and how did it end up at cold water over cee or provable bonded to cee bldg steel. . Thats expensive to get to cw sometimes. Im asking seriously I dont undermine anyone.

look at T250.66, largest aluminum GEC in the table is 250, the clamp I mentioned earlier was rated for cu or al, I did not utilize it with 250 but when I have needed larger conductor or aluminum conductor I often end up with one that will accept up to 250. (Some more comment on CEE size related to this quote is also following next quote).

Expensive? I know, but NEC doesn't generally care about cost with their rules (will not say it was never a consideration in some instances though), and 90.1 kind of tells us why.

Is that 2 gec s ending at cold water? It might have been better to bldg steel if possible suplemented with ground rod. And if cold water got a green tag see if #6 could be used for cold water since most cw clamps dont accomidate o size. But they can be found. Also gec should never be spliced in any way other than compression.

building steel does not require a supplementary electrode. Water pipe elecrode does - but the presence of a building steel electrode makes it available to be the supplementary electrode. Neither the building steel or the water pipe have any exceptions allowing GEC smaller then required in T250.66. Bonding of interior piping must also be sized per 250.66, it states this in 250.104(A)(1), so interior piping only gets #6 bonding conductor when T250.66 specifies #6 as minimum necessary.

I think he would have been better off using two of these ground clamps. He could have ran the wire thru the first clamp unspliced right to the second one.

Done it exactly the way you described many times.

 

[iwire]

Friday I happened to stop by a big box stores fire pump room ..... low and behold.


Glad our inspectors are more easy going than you all.

 

[electricalist]

look at T250.66, largest aluminum GEC in the table is 250, the clamp I mentioned earlier was rated for cu or al, I did not utilize it with 250 but when I have needed larger conductor or aluminum conductor I often end up with one that will accept up to 250. (Some more comment on CEE size related to this quote is also following next quote).

Expensive? I know, but NEC doesn't generally care about cost with their rules (will not say it was never a consideration in some instances though), and 90.1 kind of tells us why.

building steel does not require a supplementary electrode. Water pipe elecrode does - but the presence of a building steel electrode makes it available to be the supplementary electrode. Neither the building steel or the water pipe have any exceptions allowing GEC smaller then required in T250.66. Bonding of interior piping must also be sized per 250.66, it states this in 250.104(A)(1), so interior piping only gets #6 bonding conductor when T250.66 specifies #6 as minimum necessary.

Done it exactly the way you described many times.

The problem we have with bldg steel is that the inspector may ask can u show me where the bond to cee is at. (Doubt it ) so the norm has become of the methods for gec you much use at least 2 . Bldg steel only is guaranteed red tag

 

[kwired]

Friday I happened to stop by a big box stores fire pump room ..... low and behold.


Glad our inspectors are more easy going than you all.

$13.80 at this site (and is probably within price range of a similar clamp at my regular supply house) is much less then a correction order and time spent making corrections will cost. Reinspection fee alone is minimum of $50 here. You may spend just as much or even more for a different clamp and the lug. You also need not be concerned if the screw holding a separate lug should happen to work loose.

 

[iwire]

$13.80 at this site (and is probably within price range of a similar clamp at my regular supply house)

Bacon is $5.99 a pound this week at http://stopandshop.shoplocal.com/St...number=1&listingid=0&sneakpeek=N&redirected=1

is much less then a correction order and time spent making corrections will cost. Reinspection fee alone is minimum of $50 here. You may spend just as much or even more for a different clamp and the lug.

And that would be a factor if they handed out violations for that in this area. But they do not.

You also need not be concerned if the screw holding a separate lug should happen to work loose.

Truth be told I think that is the biggest concern I have about this, I agreed with Gus about that as soon as he brought it up. I also would not even argue with an inspector that did shoot it down based on 110.3(B).

However, the OP asked for opinions and mine is that is safe installation that many areas except. I think that is using commonsense and not getting overly tied up in listing issues. To me it is no different than making a change over with a conduit coupling. It will perform the tasks it need to do.

 

[kwired]

Bacon is $5.99 a pound this week at http://stopandshop.shoplocal.com/St...number=1&listingid=0&sneakpeek=N&redirected=1

........

However, the OP asked for opinions and mine is that is safe installation that many areas except. I think that is using commonsense and not getting overly tied up in listing issues. To me it is no different than making a change over with a conduit coupling. It will perform the tasks it need to do.

First part - Who doesn't like bacon?



Last part - fair enough. I do have other things I do that may be questionable, like the mentioned raceway change over with a conduit coupling, straight thread fittings in hubs allegedly intended for taper thread only....

 

[RICK NAPIER]

It is my opinion you are guessing as it is very common for panelboards with these types of lugs factory installed without 'full contact'.

Sorry I've been away from the forum for a few days. Yes I'm guessing but the point is your guessing it's sufficient contact, without listing for this application we can't tell whether it will function adequately.