Creative way of terminating GEC to ground rod

Jon456

Senior Member
Location
Colorado
The installation contractor who installed our facility's 1MW solar system apparently didn't have any U-bolt grounding clamps or acorn clamps large enough to terminate the large copper GEC's to their ground rods. So instead he attached a water pipe bonding clamp to the ground rod, then screwed on an aluminum lay-in lug to connect the GEC. I believe this is an NEC violation because this combination of parts is not L&L for this application. Am I correct?

 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
That close to ground contact, I would not be happy with the brass to aluminum bolted connection, totally independent of any component listing issues.
And is that Al lug in fact rated for use with copper wire? :angel:
 

Smart $

Esteemed Member
Location
Ohio
... Am I correct?
Chances are, both items are listed for grounding. The combination is definitely not the intended use, but you'd have to go to the manufacturers' instructions to prove it... and I've never seen any instructions furnished with those items. ;)
 

Jon456

Senior Member
Location
Colorado
Chances are, both items are listed for grounding. The combination is definitely not the intended use, but you'd have to go to the manufacturers' instructions to prove it... and I've never seen any instructions furnished with those items. ;)
Even ignoring any L&L or manufacture's instructions issues, it seems inappropriate to connect a 4/0 copper GEC to a 5/8" ground rod using only a 1/4" bronze screw to secure the lay-in lug to the water pipe clamp.

[Note: I'm not sure why 4/0 cu was specified in the plans for this GEC. It seems to be overkill in light of Table 250.66 and Section 250.66(A).]
 

Smart $

Esteemed Member
Location
Ohio
Even ignoring any L&L or manufacture's instructions issues, it seems inappropriate to connect a 4/0 copper GEC to a 5/8" ground rod using only a 1/4" bronze screw to secure the lay-in lug to the water pipe clamp.

[Note: I'm not sure why 4/0 cu was specified in the plans for this GEC. It seems to be overkill in light of Table 250.66 and Section 250.66(A).]
Seems inappropriate, yes... but not an outright violation which compels remedial measures... especially considering only a #6 GEC is all that is required for connecting to a single ground rod electrode.
 

sandsnow

Senior Member
I just cut strands off to make it fit.
Refering to pic in OP

This is one of the most common corrections I have written over the years.

I think it started with someone who was not allowed to play with tinkertoys or an erector set.

Seriously, most guys I ask tell me they ask the wholesale house for example a ground clamp for a rod to terminate 3/0 wire and this is what is sent out. Most do not question what is sent out from the wholesale house.

I see the same thing on water pipe bonding
 

iwire

Moderator
Staff member
Location
Massachusetts
Seriously, most guys I ask tell me they ask the wholesale house for example a ground clamp for a rod to terminate 3/0 wire and this is what is sent out. Most do not question what is sent out from the wholesale house.

I see the same thing on water pipe bonding
And the violation is what?

We terminate water pipe bonds like that all the time.
 

tbakelis

Senior Member
Dollar driven

Dollar driven

Obviously it's cost driven.. I had to install a horseshoe shaped clamp for 2/0 ground wire recently... Cost $80. That's a lot more than that $4 picture
 

sandsnow

Senior Member
And the violation is what?

We terminate water pipe bonds like that all the time.
I'm sincerely surprised you would think that is a good electrical connection, code violation aside.

The two products have not been investigated to be used together, therefore not listed.
110.3(B) and 250.8
 

Smart $

Esteemed Member
Location
Ohio
I'm sincerely surprised you would think that is a good electrical connection, code violation aside.

The two products have not been investigated to be used together, therefore not listed.
110.3(B) and 250.8
Just exactly how did you verify they have not been investigated to be used together?
 
I'm sincerely surprised you would think that is a good electrical connection, code violation aside.

The two products have not been investigated to be used together, therefore not listed.
110.3(B) and 250.8
The ground rod on the other hand as a good secure connection to the dirt :roll:. But seriously though, If I buy a stand alone lug, what can I ever use it for following that reasoning?
 

jrannis

Senior Member
Even ignoring any L&L or manufacture's instructions issues, it seems inappropriate to connect a 4/0 copper GEC to a 5/8" ground rod using only a 1/4" bronze screw to secure the lay-in lug to the water pipe clamp.

[Note: I'm not sure why 4/0 cu was specified in the plans for this GEC. It seems to be overkill in light of Table 250.66 and Section 250.66(A).]
When I see more than a #6 on a ground rod, I feel awkward like, one of us is ignorant. Observer or installer?
 

sandsnow

Senior Member
Just exactly how did you verify they have not been investigated to be used together?
Years ago I sent a picture of a terminal connected to a ground clamp to UL. The two products had not been investigated together and if they ever were the application would be in the installation instructions or product literature for one of the products.
 

sandsnow

Senior Member
The ground rod on the other hand as a good secure connection to the dirt :roll:. But seriously though, If I buy a stand alone lug, what can I ever use it for following that reasoning?
From UL guide info ZMVV:

Terminal connectors establish a connection between one or more conductors to a terminal plate or stud, or to any similar device by means of mechanical pressure. They are fixed in position.
 

Smart $

Esteemed Member
Location
Ohio
Years ago I sent a picture of a terminal connected to a ground clamp to UL. The two products had not been investigated together and if they ever were the application would be in the installation instructions or product literature for one of the products.
Okay, I'll accept that as verification. However, ...

From UL guide info ZMVV:

Terminal connectors establish a connection between one or more conductors to a terminal plate or stud, or to any similar device by means of mechanical pressure. They are fixed in position.
...it seems the category description leaves usage quite a bit open to not-investigated, non-specific usages.

Couple that with...
250.8 Connection of Grounding and Bonding Equipment.

(A) Permitted Methods. Equipment grounding conductors,
grounding electrode conductors, and bonding jumpers
shall be connected by one or more of the following means:
(1) Listed pressure connectors
(2) Terminal bars
(3) Pressure connectors listed as grounding and bonding
equipment

(4) Exothermic welding process
(5) Machine screw-type fasteners that engage not less than
two threads
or are secured with a nut
(6) Thread-forming machine screws that engage not less
than two threads in the enclosure
(7) Connections that are part of a listed assembly
(8) Other listed means
I believe this to be another area where the AHJ is more interested in flexing its muscle than actually being concerned with integrity and safety. IMO the connecting means has the essential integrity and safeness of sticking a #6 solid copper GEC in the terminal hole of the clamp and tightening the screw down on it.

Perhaps you'd like to witness each and every electrician tightening the screw with their torgue screwdriver??? :happysad:
 
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