Grounding/Bonding as it pertains to overground cabling methods - Utility Scale PV installs.

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pv_n00b said:
A bit of a hijack of this discussion but I'm curious how you are doing the ground electrode system in capped landfills? Most of the time in the projects I see we can't disturb the soil deeper than 6" so have to go with a UFER electrode on the cap. Some clients don't want to use a UFER and that means putting in a grounding electrode system off the cap and running long grounding electrode conductors.
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I forget, but if the service equipment is remote is there a requirement for a GES at the array?
 
pv_n00b said:
A bit of a hijack of this discussion but I'm curious how you are doing the ground electrode system in capped landfills? Most of the time in the projects I see we can't disturb the soil deeper than 6" so have to go with a UFER electrode on the cap. Some clients don't want to use a UFER and that means putting in a grounding electrode system off the cap and running long grounding electrode conductors.
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This is still under debate, however, it might come down to a 6" overground tray run overhead to a ground bar outside the cap. It's not as bad as it seems as we are building up to the edge of the cap.
 
electrofelon said:
Has that always been in there? Or am I thinking of the auxiliary electrode for say a roof mount that has gone in and out of the code a few times?
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It's said that since the 2017 NEC.

The dedicated array electrode nonsense (690.47 D) was there in 2008, out in 2011, and back in in 2014. So 2011 was the only code for a while where an electrode wasn't somehow explicitly required at the structure with the array. But in 2011 there was still a lot of other confusing verbage about DC grounding, so I think most people were still doing it.
 
Talk with the CAB team. They're very helpful. The messenger can be used as EGC, but I believe it has to be a certain type that was ordered.
 
electrofelon said:
The NEC does not use those words or anything similar
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1659641905805.png

Is this not what we are talking about? As we've established this isn't grounding as much as it is bonding?... Not trying to pick fights here but as this is bonding and this wire is non-corrosive, would that not fit the bill here?
 
Ckennedy said:
View attachment 2561640

Is this not what we are talking about? As we've established this isn't grounding as much as it is bonding?... Not trying to pick fights here but as this is bonding and this wire is non-corrosive, would that not fit the bill here?
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The EGC is what we are talking about here. The code tells you what you can use as an EGC.

250.118 Types of Equipment Grounding Conductors. The
equipment grounding conductor run with or enclosing the
circuit conductors shall be one or more or a combination of
the following:
(1) A copper, aluminum, or copper-clad aluminum conductor.
This conductor shall be solid or stranded; insulated,
covered, or bare; and in the form of a wire or a busbar of
any shape.
(2) Rigid metal conduit.
(3) Intermediate metal conduit.
(4) Electrical metallic tubing.
(5) Listed flexible metal conduit meeting all the following
conditions:
...
(6) Listed liquidtight flexible metal conduit meeting all the
following conditions:
...
(7) Flexible metallic tubing where the tubing is terminated
in listed fittings and meeting the following conditions:
...
(8) Armor of Type AC cable as provided in 320.108.
(9) The copper sheath of mineral-insulated, metal-sheathed
cable Type MI.
(10) Type MC cable that provides an effective ground-fault
current path in accordance with one or more of the
following:
...
(11) Cable trays as permitted in 392.10 and 392.60.
(12) Cablebus framework as permitted in 370.60(1).
(13) Other listed electrically continuous metal raceways and
listed auxiliary gutters.
(14) Surface metal raceways listed for grounding.
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I don't see where a steel cable can be an EGC.
 
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And one more thought:. Doesnt this conductor also need to be a GEC in addition to a EGC? Or will you be running a separate GEC? A conductor can serve as both if it meets the requirements of both.
 
electrofelon said:
And one more thought:. Doesnt this conductor also need to be a GEC in addition to a EGC? Or will you be running a separate GEC? A conductor can serve as both if it meets the requirements of both.
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I don't see how it is a GEC. In any case, a GEC has NEC requirements as well. Steel wire is not amongst the list of allowed GEC materials.

250.62 Grounding Electrode Conductor Material. The
grounding electrode conductor shall be of copper, aluminum,
copper-clad aluminum, or the items as permitted in 250.68(C).
The material selected shall be resistant to any corrosive condition
existing at the installation or shall be protected against
corrosion. Conductors of the wire type shall be solid or stranded,
insulated, covered, or bare.
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250.68 Grounding Electrode Conductor and Bonding Jumper
Connection to Grounding Electrodes.
(C) Grounding Electrode Conductor Connections.
(1) Interior metal water piping that is electrically continuous
with a metal underground water pipe electrode ...
(2) The metal structural frame of a building shall be permitted
to be used as a conductor to interconnect electrodes
that are part of the grounding electrode system ...
(3) A rebar-type concrete-encased electrode installed in
accordance with 250.52(A)(3) with an additional rebar
section extended ...
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electrofelon said:
See post number 26. The electrodes could not be present at each array section and have to be remote was my understanding. I don't have my code but handy at the moment, but wouldn't make that a grounding electrode conductor between between the electrode and the array structure?
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I suppose it could be. But, I don't see how either a GEC or an EGC can be made from a steel wire since the code does not seem to allow either to be a steel wire.

If you are going to have a single remote GES for all the arrays would it not have to follow the rules for a common GEC?
 
petersonra said:
I suppose it could be. But, I don't see how either a GEC or an EGC can be made from a steel wire since the code does not seem to allow either to be a steel wire.

If you are going to have a single remote GES for all the arrays would it not have to follow the rules for a common GEC?
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Right I agree a steel wire cannot be a gec either. I don't think I ever stated that it could be.
 
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