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Bonding and Grounding Solar Components

Earth is a emf dissipation point, if the earth is in the path. Static, and lightning voltage potentials balance there.

GFCI difference is possible, only due to earth bonding with neutral. Without it, a GFCI that is searching for a leak to trip has no path to leak to.

Bonding is needed to prevent emf voltage potentials from building dangerously… that bond, raises the chance to get electrocuted by fault current traveling to grounded path through a body. The GFCI trips in this event.
A GFCI doesn't need to be connected to a grounded or bonded system to function as intended.
 
You also don't have to use an emergency brake or turn the wheel toward the curb when parallel parking your standard transmission vehicle on a hill to keep the car from causing catastrophic damage to property or ending someone's life.
 
Correct… sort of.

But the neutral in the system does need to be bonded to ground for the hot to leak enough for a GFCI to trip.
Either a hot or neutral finding an alternate path, will trip the GFCI. This is what makes them great for many applications. And also why they can be very annoying, with only a tiny tolerance.
But, if a GFCI is happy, you can feel very confident in the safety level.
Assuming that it's not a defective unit. I always test them, at first power up. That way I know that it at least functioned, out of the box.
 
I have a Sol arc and a ground mount array.I'm also hooked to the grid. My grround mount array has no neutral wires runing to it or ground wires.
I used #8 bare copper wire to bond each panel to a ground rod at array-about 100 feet from outbuilding with Sol -Acr and 150 feet from house.
In the sol arc I ran the neutrals and grounds to a 100 amp sub panel in that outbuilding.On this property there are now 3 ground rods one at main service one at an pottery outbuilding with 100 amp sub panel and one at solar array that grounds only the array.
 
If you are not worried about meeting code, or getting inspected, you can do whatever you want. As long as you do it safely.
 
I have built a steel frame (in concrete) ground mount array about 300 feet from the house. The array is a "structure" that supports solar panels and per NEC must have its own grounding electrode, if I understand correctly. From this array to the house are 2 pair of DC circuits without any ground reference. Some (on this forum) have suggested that the house grounding electrode needs to be bonded to the solar array. Bonding two ground points 300 feet apart is something that I was taught should be avoided. I have been trying to get the proper perspective of this from the NEC point of view because our electric coop wants the install inspected by a contractor licensed master electrician.

Any useful input?

Thanks
 
1) The NEC is complicated and I can't say definitively, but I believe the ground mount array is not considered a separate structure and the NEC does *not* require separate grounding electrode(s). (It does allow auxiliary electrodes but does not specify any requirements for them.)

2) I believe the NEC does require an Equipment Grounding conductor be wired back to the house.
 
I believe it is considered a structure.
Light poles are. They will each have a grounding electrode of some design and a ground conductor from the electrical system. This does not cause ground loops because once the electrode is bonded to the pole and the conductor is wired to the fixture, they are bonded by association.
 
I believe it is considered a structure.
Light poles are. They will each have a grounding electrode of some design and a ground conductor from the electrical system. This does not cause ground loops because once the electrode is bonded to the pole and the conductor is wired to the fixture, they are bonded by association.
Yes, A lot of light poles are set up with a grounding electrodes
Yes, A lot of electrical engineers specify grounding electrodes for light poles
Yes, The NEC does allow it.
No, The NEC does not require a grounding electrode at the pole.
Yes, NEC does require an Equipment Grounding Conductor from the source of the power to the metal pole.
 
Yes, A lot of light poles are set up with a grounding electrodes
Yes, A lot of electrical engineers specify grounding electrodes for light poles
Yes, The NEC does allow it.
No, The NEC does not require a grounding electrode at the pole.
Yes, NEC does require an Equipment Grounding Conductor from the source of the power to the metal pole.
Ditto
 
NEC requires a grounding conductor from the house grounding system. While it allows the use of an auxiliary ground rod, it's not recommended. Unless you want a nearby lighting strike to enter your system.
 
Based upon the 2017 definition I believe the solar panels are the equipment and the ground mount is the structure. How is this any different than a freestanding electric sign? The NEC considers that a structure
 
Based upon the 2017 definition I believe the solar panels are the equipment and the ground mount is the structure. How is this any different than a freestanding electric sign? The NEC considers that a structure
When it comes to 'structures' the NEC seems to have as many exceptions as rules. As an example, a structure dedicated to solar equipment is handled differently than something like a detached garage. Could you please point me to the code that puts a freestanding electric sign under the 'structure' definition?

BTW: Where it will get really weird is a free-standing electric sign that has a service entrance. My guess is that the requirement for grounding electrodes at a service entrance would apply no matter where the service entrance is.
Thanks
 
I agree it's the interpretation of " structure ".
The nec definition of " structure " is " that which is built other than equipment " . Every inspector I've ever had considers the electrical sign on the pole the equipment and the pole and base the structure.
 
Let's go back to the post that brought this thread back to life:

I have built a steel frame (in concrete) ground mount array about 300 feet from the house. The array is a "structure" that supports solar panels and per NEC must have its own grounding electrode, if I understand correctly. From this array to the house are 2 pair of DC circuits without any ground reference. Some (on this forum) have suggested that the house grounding electrode needs to be bonded to the solar array. Bonding two ground points 300 feet apart is something that I was taught should be avoided. I have been trying to get the proper perspective of this from the NEC point of view because our electric coop wants the install inspected by a contractor licensed master electrician.

Any useful input?

Thanks

There are two questions buried in the post:

1) Must an Equipment Grounding conductor be run from the house to the array.
2) Should the array have local grounding electrodes?

The first question is pretty straightforward: To be NEC compliant an Equipment Grounding Conductor must be run from the house to the array.

The second question caused the conversation..... I think we all agree that the NEC does not forbid local grounding electrodes, but we are not aligned on whether they are required...... However, is probably a mute point.

I have built a steel frame (in concrete) ground mount array about 300 feet from the house.
That structure already has a lot of connection to the earth even without adding purpose-specific grounding electrodes. So, it probably does not matter much whether grounding electrodes are added or not. The potential problems with having two separate points where the Equipment Grounding Conductor system gets tied to earth is going to be there either way.
 
NEC doesn't require a ground rod at any signs or pole lights, either. That's the electrical engineers design. (A bad one)
 
Wow, this is one hell of a thread! Lots of distractions.
It needs to remain #6, until it reaches the main ground bar. It can be used to ground equipment and enclosures, along the way. But, it needs to be a wired connection for the entire length. (Don't stop and start it, on two different ground lugs, in equipment or enclosures)

This quote brings up a concern I have.
My current roof mounted solar has solid, bare #6 from the roof to the MSP and ground bus bar.
Was inspected years ago and in operation currently.

I'm looking to add another roof mounted array.
I was going to join the ground for the new array onto the existing #6 ground in a box close to the arrays and just run the single #6 for both arrays back to the main panel.

Does the NEC specify the need for dedicated ground wires from the PV to the MSP/ground?

Tim, I included your quote above because you mention not starting/stoping the ground which sounds similar to my plan.

I couldn't find any NEC call-out one way or another, but I'm ot the best at finding anything in the code.

If I end up splicing the new array ground onto the original, I'd probably use something like this:
(Unless anyone has a better recommendation)

Screenshot_20220920-193524.png
 
Let's go back to the post that brought this thread back to life:



There are two questions buried in the post:

1) Must an Equipment Grounding conductor be run from the house to the array.
2) Should the array have local grounding electrodes?

The first question is pretty straightforward: To be NEC compliant an Equipment Grounding Conductor must be run from the house to the array.

The second question caused the conversation..... I think we all agree that the NEC does not forbid local grounding electrodes, but we are not aligned on whether they are required...... However, is probably a mute point.


That structure already has a lot of connection to the earth even without adding purpose-specific grounding electrodes. So, it probably does not matter much whether grounding electrodes are added or not. The potential problems with having two separate points where the Equipment Grounding Conductor system gets tied to earth is going to be there either way.
Equipment Grounding Conductor is in the NEC in order to provide a current path back to the transformer neutral, causing a circuit protection device to trip. This is for the AC from the transformer to get back to the transformer. Take that grounding conductor to the array where there is no AC wiring, only ungrounded DC.... and DO WHAT WITH IT? It will not provide a current path back to anything because even if one of the PV wires touches the metal frame, wiring box, or whatever, there is no circuit, no path to anywhere.
 
NEC requires a grounding conductor from the house grounding system. While it allows the use of an auxiliary ground rod, it's not recommended. Unless you want a nearby lighting strike to enter your system.
The array has a total of 22 feet of 7"x4" steel channel in the ground, so it is very close to properly grounded, so is in effect an Aux ground rod when/if you connect it back to the house ground. This is the basis of the question, why connect ground to ground, to different locations? I understand the need for equipment ground path back to the transformer on a grounded transformer AC circuit. I also agree all metal should be grounded to drain static or induced current, etc. If there were AC wiring going out to the array, sure put in that ground wire, but just to the AC panel.
 
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