Splicing Aluminum GEC

Merry Christmas

NathanVA

Member
Location
Alexandria, VA
Occupation
Master Electrician and Electrical Contractor
I've got something that's stumped me and my usual go-to for answers. Installing a generator. Transfer switch on the outside of the house now becomes the main panel, I've separated out my neutrals and grounds in the existing panel (formerly main, now sub). I need to extend the water bond GEC from the existing panel to the transfer switch. It's #2 aluminum. 250.64(C)(1) to the rescue. Supply house says Aluminum can't be cad welded and so that leaves crimping. Turns out their rental crimper has been out on rental for weeks on end and they have no idea when it'll be available. I borrowed a Greenlee K05-Syncro crimping tool from another contractor at the supply house, after explaining what I'm trying to do. I thanked him for his generosity and said I would have it back to him in 2 days. I got back home and my heart sank when I see labels on the crimper that say "Copper Conductors Only"

I just keep running into brick walls here. Plus I'm pretty sure the butt splices I ordered today from the supply house aren't explicitly listed for grounding and bonding, since the counter rep couldn't find anything to that effect in the specs page.

Thoughts? Advice? Commiseration?
 

suemarkp

Senior Member
Location
Kent, WA
Occupation
Retired Engineer
Are you certain the water pipe outside is metal in the earth for 10 feet or more? If it isnt, and many have been changed to plastic, i dont believe the water bond is required to be irrevisibly spliced.

This is trying to avoid your problem instead of solving it.
 

NathanVA

Member
Location
Alexandria, VA
Occupation
Master Electrician and Electrical Contractor
Are you certain the water pipe outside is metal in the earth for 10 feet or more? If it isnt, and many have been changed to plastic, i dont believe the water bond is required to be irrevisibly spliced.

This is trying to avoid your problem instead of solving it.
Thanks for the reply. Likely metal. House is built within the last 20 years or so... If it were an older home, say 1940s, then perhaps the water pipe may have been changed out. I doubt it has, though. Good to keep in mind for future jobs!
 

suemarkp

Senior Member
Location
Kent, WA
Occupation
Retired Engineer
Really? I would think any house built in the last 20 years would have plastic from street to house. Generally polyetheleyne. But it certainly varies by region.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
...
I just keep running into brick walls here. Plus I'm pretty sure the butt splices I ordered today from the supply house aren't explicitly listed for grounding and bonding, since the counter rep couldn't find anything to that effect in the specs page.

Thoughts? Advice? Commiseration?
Not required to be so listed. Any listed pressure connector can be used. See 250.8(A)(1).
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
I'm under the impression that if there are multiple grounding electrodes (which there should be, as a water pipe electrode alone requires supplementing), only one of the electrodes need to be connected to the service neutral by an unspliced GEC. The other electrodes can be connected via bonding jumpers that may have reversible splices.

Cheers, Wayne
 

NathanVA

Member
Location
Alexandria, VA
Occupation
Master Electrician and Electrical Contractor
I'm under the impression that if there are multiple grounding electrodes (which there should be, as a water pipe electrode alone requires supplementing), only one of the electrodes need to be connected to the service neutral by an unspliced GEC. The other electrodes can be connected via bonding jumpers that may have reversible splices.

Cheers, Wayne
That seems too good to be true... I mean, I hope you're right. I'll ask around to see if other electricians have had that go in their favor with the AHJ.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
That seems too good to be true... I mean, I hope you're right. I'll ask around to see if other electricians have had that go in their favor with the AHJ.
Alright, now I had to look at Article 250 to see if I recalled correctly. I find (2017 NEC):

250.53(C) says "The bonding jumper(s) used to connect the grounding electrodes together to form the grounding electrode system shall be
installed in accordance with 250.64(A), (B), and (E), . . ." Note that 250.64(C) is the requirement that " . . . grounding electrode conductor(s) shall be installed in one continuous length without a splice or joint." So bonding jumpers don't have to be unspliced, as 250.53(C) omits reference to 250.64(C).

Then see 250.64(F). The use of the definite article in 250.64(F)(1) "The grounding electrode conductor" says to me that you need only one GEC, although 250.64(F)(2) clearly permits more than one.

So I would say that if you have, say, (2) ground rods, and one of them is served by an unspliced GEC, that suffices for 250.64(C); the other grounding electrodes could be connected to that ground rod, to the GEC, to the service grounded conductor, or to each other and ultimately to one of the proceeding locations, using a bonding jumper that may have splices. I can see an argument that if you run a conductor from an electrode to the service grounded conductor, that makes it a GEC and not a bonding jumper; that's contrary to my reading of 250.64(F), but would perhaps be hard to rebut. That argument can be sidestepped by running the bonding jumper to one of the other locations.

One thing I didn't find in Article 250 is an explicit list of places where the bonding jumper for the grounding electrode can connect; the list above is just the obvious answer. But the argument would be strengthened if there is an explicit list in a section I overlooked.

Cheers, Wayne
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
I totally agree with Wayne. The first unspliced conductor to the first electrode is the grounding electrode conductor and from there we connect all other electrodes via a bonding jumper. They do not need to be continuous once you get to the first electrode.
 
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