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Bonding and Grounding Solar Components

fisherus

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I'm installing a Sol-Ark 12K system on my off-grid farm and have a question about grounding and bonding. In many videos I have watched, I have noticed that a green 6AWG THNN stranded copper wire is ran inside the conduit along with the PV wires from the array to the place where the hybrid inverter is mounted. Is this wire attached to the grounding rod of the array and to all the neutral lugs in switches and boxes from the array to the Sol-Ark for bonding purposes? What is the purpose for this wire? Is it necessary for an off-grid system?
 
I'm installing a Sol-Ark 12K system on my off-grid farm and have a question about grounding and bonding. In many videos I have watched, I have noticed that a green 6AWG THNN stranded copper wire is ran inside the conduit along with the PV wires from the array to the place where the hybrid inverter is mounted. Is this wire attached to the grounding rod of the array and to all the neutral lugs in switches and boxes from the array to the Sol-Ark for bonding purposes? What is the purpose for this wire? Is it necessary for an off-grid system?
It attaches to the rest of the grounding system.
NOT TO THE NEUTRALS
Neutral and ground are only connected in one place.
This is usually at the main service panel.
This is called the N/G bond.
If you are completely off grid.(no grid available)
N/G bond should be located at the first means of disconnect. I would need to know more about your system, to determine where it should be.
 
I'm installing a Sol-Ark 12K system on my off-grid farm and have a question about grounding and bonding. In many videos I have watched, I have noticed that a green 6AWG THNN stranded copper wire is ran inside the conduit along with the PV wires from the array to the place where the hybrid inverter is mounted. Is this wire attached to the grounding rod of the array and to all the neutral lugs in switches and boxes from the array to the Sol-Ark for bonding purposes? What is the purpose for this wire? Is it necessary for an off-grid system?

The line that caught my eye is this:
"Is this wire attached to the grounding rod of the array"

Is the array on the same structure as the rest of the equipment or is it a ground mount?

In general, multiple grounding rods should be avoided and if the array is on the same structure they should be removed.
 
In general, multiple grounding rods should be avoided and if the array is on the same structure they should be removed.
A little clarification: There may be multiple grounding electrodes. In fact it is often required. However, they should all tie to the Equipment Grounding system at one point.
 
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The line that caught my eye is this:
"Is this wire attached to the grounding rod of the array"

Is the array on the same structure as the rest of the equipment or is it a ground mount?

In general, multiple grounding rods should be avoided and if the array is on the same structure they should be removed.
I agree
But, the industry standard is when in doubt, just drive another rod. lol
 
Actually, I believe that the Sol-Ark should do it internally.
I do not think the Sol-Ark does any N-G bond.

The sol-ark systems are designed with what I call a 'common neutral'. What I mean by this is the input natural is electrically the same as the output neutral. This means that the N-G bond for the house is also 'seen' by any circuits/loads being driven by the Sol-Ark.
 
I do not think the Sol-Ark does any N-G bond.

The sol-ark systems are designed with what I call a 'common neutral'. What I mean by this is the input natural is electrically the same as the output neutral. This means that the N-G bond for the house is also 'seen' by any circuits/loads being driven by the Sol-Ark.
That makes perfect sense.
Because, it's always connected to the source input.
 
This is a ground mount. The one thing I don't want to create is a potential for a ground loop. I think that driving another rod would be the fastest way to create one. From what I am hearing, I don't need to run any wire for a neutral or anything else then? I've put in a ground rod for the AC panel and the AC current only.
 
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I do not think the Sol-Ark does any N-G bond.

The sol-ark systems are designed with what I call a 'common neutral'. What I mean by this is the input natural is electrically the same as the output neutral. This means that the N-G bond for the house is also 'seen' by any circuits/loads being driven by the Sol-Ark.
As an aside, I believe the common neutral design is by far the best design for stationary systems. Separate-ground systems like MPP and Growatt add unnecessary complications and can be a lot more difficult to set up correctly and safely.
 
This is a ground mount. The one thing I don't want to create is a potential for a ground loop. I think that driving another rod would be the fastest way to create one.
Since there's no neutral, at the array. A rod there won't be an issue. (If there were, you would keep them separate)
Just run the ground wire back to the main ground bar, for the system.
 
This is a ground mount. The one thing I don't want to create is a potential for a ground loop. I think that driving another rod would be the fastest way to create one. From what I am hearing, I don't need to run any wire for a neutral or anything else then? I've put in a ground rod for the AC panel and the AC current only.
I believe the NEC requires the Equipment Grounding Conductor for the Panels to be tied to the main grounding system of the property.
I also believe the NEC *allows* additional grounding electrodes at the array, but I am not sure I would add one.
 
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A rod at the array is a good thing, in my opinion.
This keeps the array at the same zero potential as the earth around it.
Since there's no neutral, at the array. A rod there won't be an issue. (If there were, you would keep them separate)
Just run the ground wire back to the main ground bar, for the system.
Are you talking about a wire through the conduit from the array to the Sol-Ark or the array to the ground rod? I've already grounded the panels and ground mount to the ground rod.
 
Are you talking about a wire through the conduit from the array to the Sol-Ark or the array to the ground rod? I've already grounded the panels and ground mount to the ground rod.
First priority is the wire through the conduit. From the array to the main ground bar.
Optional array to local ground rod, should be also connected to this wire.
Preferably this would be one continuous unbroken wire. From the main ground bar, through the array ground connection, and continued on to the array ground rod.
 
First priority is the wire through the conduit. From the array to the main ground bar.
Optional array to local ground rod, should be also connected to this wire.
Preferably this would be one continuous unbroken wire. From the main ground bar, through the array ground connection, and continued on to the array ground rod.
I follow the logic but not sure if I agree. If a ground rod is driven at the location of the ground mount, I'd prefer to ground the system there instead of giving lightning a direct path inside. If the combiner box is mounted at the array, ground it there as well. If it's inside, then ground it to the main ground in the house
 
Lighting is going straight to the earth. The magnetic pulse it would create, could travel on this wire. But, it would also be traveling on the other wires as well. And they go straight into the inverter. There should be Lighting arrestors installed at both ends.
That #6 ground wire cannot carry a Lighting strike. It will just blow apart. This grounding system has nothing to do with Lighting protection.
 
What I have done at the ground mount is put an two 5/8" x 8ft ground rods, spaced one on each side of the ground mount coupled to a 6AWG bare stranded copper wire attached to the stanchion and panels then to the rods on each side. I also ran another wire between each rod and grounded my disconnect switches and combiner boxes to the rods. I have two more disconnect switches outside my solar shed that feed the PV strings to the Sol-Ark. So, what do I need from here. I have 2 Midnite Solar lightning arresters and was thinking about using one on the disconnect switch at the ground mount and the other at the Sol-Ark? My thinking is that the green 6AWG wire I've seen run through the PV conduit sole purpose is for bonding all switches, boxes, etc. together. Am I correct in assuming this because if I don't need to do it, it's about a $450 savings for the wire
 
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The array grounding system is useless in a bolt of direct lightning. Everything in the system will probably be destroyed and there is no grounding in the world that will prevent it. In order to prevent damage from a direct hit requires a lightning suppression system and that will be a completely separate system with air terminals and its own grounding.

This is what I believe is required and optional for grounding ground mount arrays in the NEC

(I put the question mark on the grounding electrodes for the array because I am 99% sure they are optional.)1649102040070.png




Note: If the ground mount rack is metal, it is hard to avoid some amount of grounding at the array even if there is no grounding electrodes

If the array is mounted on the house, the code allows an additional grounding electrode but does not require it. You should not do it.
1649103821591.png
 
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