Earth grounds

Pgh-skip

New Member
Joined
Jan 18, 2022
Messages
30
I'm installing an Eg4 48 volt 3 kw off grid inverter. in place of a 24 volt Magnum inverter. The system used lead/acid batteries that were recharged using a gas generator. As I was connecting the new Eg4 inverter, I noticed that the distribution panels ground bus bar was not connected to an earth ground. I have two questions. Shouldn't the distribution panels ground bus bar be connected to a grounding rod? And can I connect the distribution panel to a ground rod that I have installed for the pv panels? Or should I install a separate ground rod for the panel? Any help will be greatly appreciated.
 

Zwy

Photon Sorcerer
Joined
Jan 3, 2021
Messages
2,089
Location
Timbuktu
Diagram and photos would help.

Only one ground rod and should be at the point of N-G bond unless main grid service panel (first disconnect or breaker device per NEC) is located at a separate structure. If that is the case, then a ground rod at the separate structure but you do not bond N-G at the second panel on the separate structure.

Need any more help, post up diagrams and photos and give more information such as any grid feed to the system, location of N-G bond, whether separate structures exist and where the inverters are located.
 

Pgh-skip

New Member
Joined
Jan 18, 2022
Messages
30
My system is totally off grid. Would there be a problem if I run a 6 awg bare ground wire from my ground bus bar in my panel to a ground rod I'm installing for my pv array. The ground rod is approximately 125' from my service panel which will be located next to pv panels.
 

jasonhc73

Cat herder, and dog toy tosser.
Joined
Oct 1, 2019
Messages
1,855
Location
Wichita, Kansas
The PV panels need their own grounding rod.
Here is the kit/parts I used for mine.

THE PV grounding is not part of the AC circuit. DO NOT MIX THEM.



Attach the grounding wire to the panels so that every panel makes contact, either through the mounting rail or directly bonded to each panel.

Run the grounding wire out as far as it will go and that's where you put the grounding rod in the dirt.
 

robby

Photon Vampire
Joined
May 1, 2021
Messages
2,821
Yes there is a lot of confusion on this issue and not much clarity but the Consensus seems to be that PV Panels should be on their own ground rod and not connected to the rest of the Grounding system. If it helps I can tell you that my Inspector removed the Bond I had put in and told me he would not Pass it if the Panels were bonded to the rest of the system.
 

jasonhc73

Cat herder, and dog toy tosser.
Joined
Oct 1, 2019
Messages
1,855
Location
Wichita, Kansas
Yes there is a lot of confusion on this issue and not much clarity but the Consensus seems to be that PV Panels should be on their own ground rod and not connected to the rest of the Grounding system. If it helps I can tell you that my Inspector removed the Bond I had put in and told me he would not Pass it if the Panels were bonded to the rest of the system.
I finally had a realization the other day talking with an electrician. (Mind you most electricians don't know anything about the physics of electricity or how transformers work.)

I have no other explanation that makes sense other than this idea.

The metal surround/frame of the solar panel gets energized because of induced current, not because of the PV cells are connected to the frame, just because the cells are near the PV cells.

Think how the secondary coils of a transformer get energized from the primary. It's all induced current, there is no direct physical contact of the wires.
 

Pgh-skip

New Member
Joined
Jan 18, 2022
Messages
30
I finally had a realization the other day talking with an electrician. (Mind you most electricians don't know anything about the physics of electricity or how transformers work.)

I have no other explanation that makes sense other than this idea.

The metal surround/frame of the solar panel gets energized because of induced current, not because of the PV cells are connected to the frame, just because the cells are near the PV cells.

Think how the secondary coils of a transformer get energized from the primary. It's all induced current, there is no direct physical contact of the wires.
 

Pgh-skip

New Member
Joined
Jan 18, 2022
Messages
30
Since my distribution panel is not connected to the grid, does it need to be connected to an earth ground? I will only wire the pv panels and rails to a separate ground rod. If my service panel needs to be earth grounded, I'll install a separate ground rod for it. But, my question is does my service panel need to be earth grounded?
 

jasonhc73

Cat herder, and dog toy tosser.
Joined
Oct 1, 2019
Messages
1,855
Location
Wichita, Kansas
Since my distribution panel is not connected to the grid, does it need to be connected to an earth ground? I will only wire the pv panels and rails to a separate ground rod. If my service panel needs to be earth grounded, I'll install a separate ground rod for it. But, my question is does my service panel need to be earth grounded?
Yes.

Not for completing a circuit and your AC circuits to work, but for safety in case any wire in your circuits become open.

Watch the 1st 5 or so minutes of this:
 

robby

Photon Vampire
Joined
May 1, 2021
Messages
2,821
One thing I find amusing is his assumption that Hand to Hand or Hand to foot the human bodies resistance is 1Kohm. That is a highly subjective statement! My own normal hand to hand resistance is roughly 2Mohms and if I am sweating it will drop down to 500Kohm. I am not all that calloused but I know electricians that can touch 120V circuits and they feel almost nothing. I touch them and I most certainly feel it. While other guys will jump out of their skin from a 120V touch like they got shot. Anyway never touch a wire that your not sure it is de-energized.
 

Pgh-skip

New Member
Joined
Jan 18, 2022
Messages
30
So, when I earth ground my distribution panel, the panel should not have the ground and neutrals bonded. Since there is no grid tie, this grounding system becomes an equipment ground. Is this correct? In this case I want the neutrals and grounds separated.
 
Top