Is additional array grounding required to be continuous or irreversably spliced?

[SunFish]

When I'm installing my additional array ground per 690.47(D) in the 2014 code is this required to be irreversibly spliced all the way from the array to the ground rod?

We have been irreversibly crimping this #6 Bare additional array ground onto our racking & module equipment ground using a Brundy C-crimp, but this is expensive. I'm not seeing anything in the code that says this has to be irreversibly spliced, could we be using a split bolt for this connection instead of the C-crimp?

 

[jaggedben]

When I'm installing my additional array ground per 690.47(D) in the 2014 code is this required to be irreversibly spliced all the way from the array to the ground rod?

We have been irreversibly crimping this #6 Bare additional array ground onto our racking & module equipment ground using a Brundy C-crimp, but this is expensive. I'm not seeing anything in the code that says this has to be irreversibly spliced, could we be using a split bolt for this connection instead of the C-crimp?

I would say it's very unclear. On the one hand,the new 690.47(D) doesn't mention 250.64 like other parts of 690.47 do, and it refers to the electrode as auxiliary. On the other hand, it says it's a grounding electrode conductor and 250.64 governs that.

 

[pv_n00b]

#1, it's pretty easy to use the exceptions to 690.47(D) to get out of having to do it.

#2, the conductor that connects the auxiliary grounding electrode to the equipment being grounded is still identified as a grounding electrode conductor and there is no exception anywhere that I have seen that says it can be installed any differently that any GEC. So we are kind of stuck with the whole irreversible connection and bonding of the raceway thing. Go back to #1 and take a real close look at exception 2. If you can show that you can install the 690.47(D) electrode within 6ft of the existing building electrode then you don't have to install it.

 

[SolarPro]

See also Exception 1:

If you are putting a PV array on a building and the load served by the interactive PV system is the building, then the load is integral with the array.

Who could argue with that logic? Now you have two exceptions you can point two.

Perhaps most importantly, the 2017 Code revises this content as follows:

B) Additional Auxiliary Electrodes for Array Grounding. Grounding electrodes shall be permitted to be installed in accordance with 250.52 and 250.54 at the location of groundand roof-mounted PV arrays. The electrodes shall be permitted to be connected directly to the array frame(s) or structure. The grounding electrode conductor shall be sized according to 250.66. The structure of a ground-mounted PV array shall be
permitted to be considered a grounding electrode if it meets the requirements of 250.52. Roof mounted PV arrays shall be permitted to use the metal frame of a building

That just says you can put an additional auxiliary electrode in if that's what get you out of bed in the morning. The rest of us can go about our business. It is not required by Code.

 

[Fulthrotl]

When I'm installing my additional array ground per 690.47(D) in the 2014 code is this required to be irreversibly spliced all the way from the array to the ground rod?

We have been irreversibly crimping this #6 Bare additional array ground onto our racking & module equipment ground using a Brundy C-crimp, but this is expensive. I'm not seeing anything in the code that says this has to be irreversibly spliced, could we be using a split bolt for this connection instead of the C-crimp?

.
these can be had for a smidge over $2 each....

YC6L12

the heavy duty direct burial and concrete encasement ones run about $7 each.

if you have to tap off to hit each piece of raceway, and it's exposed, the cheaper
ones will work ok.

 

[jaggedben]

#2, the conductor that connects the auxiliary grounding electrode to the equipment being grounded is still identified as a grounding electrode conductor and there is no exception anywhere that I have seen that says it can be installed any differently that any GEC. So we are kind of stuck with the whole irreversible connection and bonding of the raceway thing. Go back to #1 and take a real close look at exception 2. If you can show that you can install the 690.47(D) electrode within 6ft of the existing building electrode then you don't have to install it.

Sticking with 2014 here (since thank goodness 2017 lets us out of the whole thing again, hopefully for good this time)...

They called it an auxiliary electrode, which harkens back to 250.54. That section is vague as to whether a GEC is required but I would think most auxiliary electrodes do not get subjected to 250.64 requirements. Anyway, the point is, since they called it auxiliary I would say one can make the argument that none of the normal GES requirements apply except what's explicitly stated in 690.47(D), which doesn't mention 250.64.

Bottom line: ask your AHJ.

 

[Carultch]

Sticking with 2014 here (since thank goodness 2017 lets us out of the whole thing again, hopefully for good this time)...

They called it an auxiliary electrode, which harkens back to 250.54. That section is vague as to whether a GEC is required but I would think most auxiliary electrodes do not get subjected to 250.64 requirements. Anyway, the point is, since they called it auxiliary I would say one can make the argument that none of the normal GES requirements apply except what's explicitly stated in 690.47(D), which doesn't mention 250.64.

Bottom line: ask your AHJ.

The auxiliary grounding electrode rules are so vague that you could run CAT5 to it as a GEC and use a 3 foot ground rod, which would make no sense at all.

 

[jaggedben]

The auxiliary grounding electrode rules are so vague that you could run CAT5 to it as a GEC and use a 3 foot ground rod, which would make no sense at all.

Yes, and while 690.47(D) wouldn't let you do that (it invokes 250.166), the OP's question lies right in within the remaining vagueness that is not directly addressed.