Grounding confusion

PsychoticEpisode

Solar Addict
After watching Will vid and the vid he posted in the disruptions I'm totally lost now. So ill describe my system and maybe you guys can tell me if I need an earth ground. I have a 24v system with the panels setting on cinderblocks on the ground. They all connect to my shed that is also sitting on blocks. The pv wire runs throw a combiner box then to a main bus bar. From the bus bar it move to the batteries or the inverter. From the inverter is runs 240v to a box mounted on a tree that my RV plugs into. My RV is setting on its wheels and cinder blocks. I have a earth grounding rod but I have not installed it yet because I did not know where to do it at.
Do I even need an earth ground?
If I need an earth ground what locations should I put it?
 

FilterGuy

What, me worry?
First: The purpose of earth ground is to keep the system voltage from floating to a potential that is significantly different than the earth.
I don't know where you are located, but in North America it is required by code. (From what you describe, it does not sound like anyone is checking code though)

I would recommend grounding the system at a single point, but I would need to know a lot more about the system to say where that one point should be....so the rest of this post is speculation.

My first assumption is that you are in North America and you are using 240V split phase. If I am wrong, then ignore the rest of this.

If the RV was wired for plugging into Power monuments at camp grounds, then the ground wire at the plug-in on the RV is tied to the AC Ground that runs through the RV. In addition, the RV probably does NOT have a Neutral-Ground bond. Instead the RV counts on the N-G bond from the power monument.

Given the above assumptions, the 'box-on-a-tree' is the equivalent to the campground power monument and the earth ground should be there or at the inverter. I would also put an Earth-Neutral bond at the point the system ties to earth ground.

You should review at least the first 3 of the grounding resources. This is the first and it has links to the others.
 

HRTKD

Boondocker
If everything was deployed on or in the RV then no ground would have been required. But since you put devices outside the RV, those devices need to be grounded. My opinion is that the external devices cannot use the RV as a ground. It has to be separate. I agree with FilterGuy's conclusions.

I think the inverter and solar panels need to use the grounding rod.

I'm not an electrician though. My opinions are based on what I've read here on the forum.
 

PsychoticEpisode

Solar Addict
First: The purpose of earth ground is to keep the system voltage from floating to a potential that is significantly different than the earth.
I don't know where you are located, but in North America it is required by code. (From what you describe, it does not sound like anyone is checking code though)

I would recommend grounding the system at a single point, but I would need to know a lot more about the system to say where that one point should be....so the rest of this post is speculation.

My first assumption is that you are in North America and you are using 240V split phase. If I am wrong, then ignore the rest of this.

If the RV was wired for plugging into Power monuments at camp grounds, then the ground wire at the plug-in on the RV is tied to the AC Ground that runs through the RV. In addition, the RV probably does NOT have a Neutral-Ground bond. Instead the RV counts on the N-G bond from the power monument.

Given the above assumptions, the 'box-on-a-tree' is the equivalent to the campground power monument and the earth ground should be there or at the inverter. I would also put an Earth-Neutral bond at the point the system ties to earth ground.

You should review at least the first 3 of the grounding resources. This is the first and it has links to the others.
Unfortunately the papers are not there it just loops back to the same post.

It sounds like I just need 1 ground at and connect it to the inverter is that correct?
 

PsychoticEpisode

Solar Addict
One Last question can you attach 2 inverters on 2 different banks to the same ground bar?

Thank you guys again for the help, you never fail to fix my mess-ups.
 
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FilterGuy

What, me worry?
One Last question can you attach 2 inverters on 2 different banks to the same ground bar?
yes..... there should be only one point that the whole system gets tied to earth ground.

I assume you are using two inverters to get the 240?

Could you please provide a diagram of your system?
 

PsychoticEpisode

Solar Addict
yes..... there should be only one point that the whole system gets tied to earth ground.

I assume you are using two inverters to get the 240?

Could you please provide a diagram of your system?
No I have 1 system making 240v and an 2nd system at 120v to run my shed and other things. 2 system on 2 banks so if one is down it will not effect the other.
 
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