Unintended ground rod

[Bluedog225]

In 100% convinced by those who say everything should be bonded together and run to a single earth ground consisting of two grid rods at least 6’ aside and bonded together.

This includes the frames of solar panels and the racking system.

But, what do I make of a racking system that is planted in the earth? As in pipes driven into the ground.

Have I created the potential for a ground loop? Or some other issue?

 

[AntronX]

Yes.

 

[Rednecktek]

You're screwed. Gotta tear the whole system out and replace with non conductive pipe and non conductive conduit and run a #6 copper wire through non conductive steel conduit under ground all the way back to the main panel...

Sigh... and people wonder why it's so complicated...

 

[RadioChief]

I don't see an issue here. You can't have too many grounds. People might be confusing the single neutral to ground bonding point with grounding in general.

 

[hwy17]

Pools are another one that creates second earthing points.

Don't worry about it, just make one intentional grounding point. The electrons will respect the intentionality and go there.

 

[Bongbong]

Ground loops will happen and you probably won't notice until a major fault occurs, unless you have equipment that is designed to detect them and that requires you to take action. The solution AntronX gave you is probably your best long term option, it is certainly the one I would implement if I were you.

 

[Crowz]

Water seems to have potential to cause problems too

Actually its a fake in its a demolition vid they are passing off as a lightning strike but I figured I'd post it anyways.


But back to the water effect that made me look for the vids to start with.

I was blaming my grounding issues and pv lines as the cause of the surges coming into my workshop. It now seems that the surges are coming thru the water lines into the workshop and jumping to the power lines I have running beside the water lines. I moved several of the cables to a different entrance. Only things that still touch the water pipes at that entrance are getting zapped. The cables do not travel out in the yard any.

So how does one prevent this if its such a no no having grounds at the array or other locations when the water lines can do this? These are pvc pipes so I have no idea how one would even ground plastic pipes.

 

[Quattrohead]

All possible grounding points must be bonded together with substantial copper, this minimumises potential differences between them.

 

[ricardocello]

But, what do I make of a racking system that is planted in the earth? As in pipes driven into the ground.

I’ve got multiple 46’’ cast aluminum screws in the ground supporting 2” galvanized pipe for my ground mounts.
9 total! You can’t get more grounded than that. And they are all bonded together locally with 6 AWG.

And yet, I sleep just fine at night.
I just don’t worry that my 8 AWG EGC wire in the conduit back to the house might carry a bolt from Zeus back to the house.
I guess I’m just abusing the NEC auxiliary ground rod rule, and feeling good about it.

In all seriousness, sometimes there’s just nothing you can do.

 

[timselectric]

But, what do I make of a racking system that is planted in the earth? As in pipes driven into the ground.

Have I created the potential for a ground loop? Or some other issue?

It is what it is.
Sometimes bad things can't be avoided.

 

[Steve_S]

Question (rhetorical).
Ground Rods on top of houses, barns & other structures are wired to WHAT ? (hint, not the electrical ground point)
Are all grounds rods for Electrical Only or for Lightning Management as well ?
Solar Panel frames & the Racking are made of aluminum and that can attract lightning so you do have to consider that.
My ground mount setup is Grounded to a grounding plate @ Array. There is NO AC Power at the array (equipment is in a building 50' away).
My Solar Controllers, Inverter etc are all grounded in the Powerhouse to the proper ground as used by my AC System.

Some people will "ground" the Negative of their batteries to an Earth Ground. Some even do a separate one for that and have issues...
A few get mixed up with DC Negative thinking in an Automotive way (Vehicle & Residential are obviously different but still...) Never goes well.

3 Points of Interest:
AC System is the 1st Beast, DC system is the 2nd Beast, and Lightning is the 3rd that will get ya when not paying attention. Each have their own requirements along with quirks & foibles that go with it, especially when interconnecting them.

 

[timselectric]

Answer (Rhetorical) lol
Not exactly.

 

[wdwtx2.0]

Both of my arrays are six steel pipes buried five feet deep.
Obviously they are one big ground rod.
They are also grounded via EGC back to my system ground at my breaker panel.
No biggie. Nothing I can do about it.

 

[seneysolar]

What about anyone with a propane tank and ___ feet of copper line buried in the ground? Or a point well with ___ feet of steel pipe in the ground? Both of these are likely to lead to appliances that are grounded, and ultimately grounded to the main panel.

It is my understanding multiple grounds are not bad as long as they all have the same potential. You don't want 2 points in a circuit to have a different ground reference. I assume this is why NEC wants your PV system ground ran all the way back to the main panel ground. If they all run back to the same point, they all have same potential.

 

[ricardocello]

Or a point well with ___ feet of steel pipe in the ground

250 ft, It is grounded back to the panel.

 

[wpns]

It is my understanding multiple grounds are not bad as long as they all have the same potential

Which will not be true in a nearby or direct lightning strike. It’ll depend on your ground points, their characteristics, the soil between them, and a bunch of other factors. All you can do is the best you can do and hope it’s good enough. The towers atop Mount Washington, which is very rocky at the top get direct lightning strikes hundreds of times a year without damage, but they are engineered to deal with it.

 

[SoggyShoes]

Question (rhetorical).
Ground Rods on top of houses, barns & other structures are wired to WHAT ? (hint, not the electrical ground point)
Are all grounds rods for Electrical Only or for Lightning Management as well ?
Solar Panel frames & the Racking are made of aluminum and that can attract lightning so you do have to consider that.
My ground mount setup is Grounded to a grounding plate @ Array. There is NO AC Power at the array (equipment is in a building 50' away).
My Solar Controllers, Inverter etc are all grounded in the Powerhouse to the proper ground as used by my AC System.

Some people will "ground" the Negative of their batteries to an Earth Ground. Some even do a separate one for that and have issues...
A few get mixed up with DC Negative thinking in an Automotive way (Vehicle & Residential are obviously different but still...) Never goes well.

3 Points of Interest:
AC System is the 1st Beast, DC system is the 2nd Beast, and Lightning is the 3rd that will get ya when not paying attention. Each have their own requirements along with quirks & foibles that go with it, especially when interconnecting them.

When I was in construction we did a couple of house roof lightning rods. They were completely isolated from ALL the wiring in the home. They had several large cables go straight to deep ground rods.

One was because lightning struck about 100' from the house when a framer was on a aluminum ladder. Apparently there was arcing between the ladder and his hammer. It shocked (or scared) him enough to make him piss himself.
His partner was pissed because the next day he spent a ton buying all new fiberglass ladders.

 

[timselectric]

When I was in construction we did a couple of house roof lightning rods. They were completely isolated from ALL the wiring in the home.

This is dangerous. They must be bonded to the electrical grounding system, to make them safe to touch.
Usually this is done at a single point, at ground level. Preferably below grade.

 

[robbob2112]

This is dangerous. They must be bonded to the electrical grounding system, to make them safe to touch.
Usually this is done at a single point, at ground level. Preferably below grade.

Do you mean it should be connected to the main ground rod as a second connection? I.E. just another clamp around the rod with the wire from the roof attached?


Different but similar question - my telco when they put in the network interface box put a short rod 6 inches away from the main house ground but didn't attach it with a wire, should it be?

 

[timselectric]

Do you mean it should be connected to the main ground rod as a second connection? I.E. just another clamp around the rod with the wire from the roof attached?

The lighting protection system will have its own ground rods. Usually at each corner of the building and possibly more spaced between, if the distance is great.
Then a single connection from the electrical system ground rod to the nearest lighting protection system ground rod.

Different but similar question - my telco when they put in the network interface box put a short rod 6 inches away from the main house ground but didn't attach it with a wire, should it be?

Yes
I personally wouldn't have installed the auxiliary rod. But since it's there, it must be bonded to the rest of the grounding system.