Grounding panels on RV roof?

[chaostactics]

Im a bit confused. I've watched a number of solar installs on RVs on YouTube from the bigger channels (I'm 100% aware it doesn't mean they're correct). And I've never seen them use grounding lugs on the panels.

I have 600 watts of panels going to a victron 100|50 mppt. The mppt is connected to the ground lug on the Victron multiplus, which is connected to a lynx distributor, which has a chassis ground.

The RV is a rubber membrane roof. Do I need to ground the panels?

 

[time2roll]

Generally the ground is skipped on a mobile system.

 

[Ampster]

Generally the ground is skipped on a mobile system.

I would assume the chassis is a partial ground but the tires keep it from being an Earth ground. Because of that I assume the risks of lightning strikes are different in RVs than in homes.

 

[Pappion]

I would assume the chassis is a partial ground but the tires keep it from being an Earth ground. Because of that I assume the risks of lightning strikes are different in RVs than in homes.

My Travel Trailer has a steel Tongue Jack. Also 4 steel Stabilizing Jacks.

 

[Ampster]

My Travel Trailer has a steel Tongue Jack. Also 4 steel Stabilizing Jacks.

I guess that is some protection in a lightning strike. Hopefully you are not the highest structure connected to ground in the nearby neighborhood?

 

[Pappion]

I guess that is some protection in a lightning strike. Hopefully you are not the highest structure connected to ground in the nearby neighborhood?

The tree near me sacrificed itself.

I think the problem with mobile would be the wire size and ground stake. Lightning could vaporize the wire.

 

[RoadTurtle]

The tree near me sacrificed itself.

I think the problem with mobile would be the wire size and ground stake. Lightning could vaporize the wire.

At my house, I had a lightening strike on a tree in the backyard, while power lines wree at the street. Over the next 6 months, I replaced just about all the electrical equipment in the house... none covered by insurance, since the time had passed, and the electrical line wasn't struck.

 

[Pappion]

At my house, I had a lightening strike on a tree in the backyard, while power lines wree at the street. Over the next 6 months, I replaced just about all the electrical equipment in the house... none covered by insurance, since the time had passed, and the electrical line wasn't struck.

Maybe my electronics got lucky. Maybe I made my own luck.
Surge Protector at the Pedestal survived. The power lines are buried.
TV, DVD, and Wii were not plugged in due to thunderstorm warnings. Power strip has a surge protector.
Laptop 12v adapter cigarette socket has a large power line filter. 12v sound system already had one.
I added (audio) 12v power line filters for control boards of Frig and Water Heater.
Also spread a lot of Clip-ON Ferrite Beads around. Bought a large packet from Amazon.

I started with the 12v power line filters on my old A-Frame. It helped with random issues, like a confused Frig display. Turned out it was a grounding problem. Cheap bums, no ground bus, just 3 large closed end crimp connectors for dozens of wires.

My parents house suffered from a power line lightning hit. Only the TV survived as it was plugged into a great surge protector power strip. I talked them into replacing the strip, IMHO just good for one use.

 

[chrisski]

My Travel Trailer has a steel Tongue Jack. Also 4 steel Stabilizing Jacks

But still not a copper rod dug in the the earth.

If you are going to install grounding on the panels for lightning, recommend doing in accordance with local code.

I’ve been 3’ to 6’ in the earth for a copper grounding bar. I have rarely been anywhere I could pound a bar that deep and I have never been in a place where I could recover the copper if I drove the bar in.

 

[emerge411]

Im a bit confused. I've watched a number of solar installs on RVs on YouTube from the bigger channels (I'm 100% aware it doesn't mean they're correct). And I've never seen them use grounding lugs on the panels.

I have 600 watts of panels going to a victron 100|50 mppt. The mppt is connected to the ground lug on the Victron multiplus, which is connected to a lynx distributor, which has a chassis ground.

The RV is a rubber membrane roof. Do I need to ground the panels?

I noticed the same thing but I did end up connecting the panel frames to my grounding bus as detailed in fitlerguys mobile grounding doc. Folks using factory/existing wiring only have two wires so they dont add a ground. Any airstream install is likely to be connected to chassis ground though the skin, so I dont think it is something that matters a ton. I was already running eight wires for my install so i added a 9th. I dont think there is going to be much if a difference in the instance of a lighting strike...

https://diysolarforum.com/resources/grounding-made-simpler-part-4-mobile-systems.159/


The white wire is my ground. It is a single wire running to all the panels that has the insulation stripped in a small section to connect to the panel via one of these

 

[Checkthisout]

Lots of people still confusing ground rods and the egc.

 

[HRTKD]

Any PV mounting that uses the typical Z brackets may not have a connection to the Airstream aluminum skin that you think it does. Z brackets use butyl tape between the aluminum skin and the foot of the bracket. That's not a connection, that's a barrier. I wouldn't count on the screw/bolt making that connection either.

 

[Supervstech]

But still not a copper rod dug in the the earth.

If you are going to install grounding on the panels for lightning, recommend doing in accordance with local code.

I’ve been 3’ to 6’ in the earth for a copper grounding bar. I have rarely been anywhere I could pound a bar that deep and I have never been in a place where I could recover the copper if I drove the bar in.

There are no copper ground rods…

You aren’t pounding in a Bar of copper anywhere…

It’s a steel rod plated or dipped in copper…

 

[HRTKD]

This just in...

The newest TikTok challenge is to drive a rod of pure copper 6' into the ground.

 

[chrisski]

There are no copper ground rods…

You aren’t pounding in a Bar of copper anywhere…

It’s a steel rod plated or dipped in copper…

But a grounding rod is something pounded in the ground.

Since you’re an electrician, Do you think grounding panels on an RV to a frame is valid if that frame ground stops at two steel supports that may sit on top of the soil or may rest on top of a plastic leveler.

 

[Checkthisout]

But a grounding rod is something pounded in the ground.

Since you’re an electrician, Do you think grounding panels on an RV to a frame is valid if that frame ground stops at two steel supports that may sit on top of the soil or may rest on top of a plastic leveler.

Low voltage arrays are not required to be grounded.

(I think)

 

[chrisski]

Low voltage arrays are not required to be grounded.

(I think)

My grounding rod is not intended for the average RV build of 600 watts of panels.

My setup is 2550 watts of panels with a 3000 watt inverter I run 6 hours at 2000 watts.

At some point a grounding would be wise.

 

[Checkthisout]

My grounding rod is not intended for the average RV build of 600 watts of panels.

My setup is 2550 watts of panels with a 3000 watt inverter I run 6 hours at 2000 watts.

At some point a grounding would be wise.

What's the array voltage?

 

[chrisski]

What's the array voltage?

It’s currently 66 VOC at the panels, 24 volt inverter, 3000 watt inverter, constant load 2000 watts for 6 hours.

I’m wondering if there’s a book answer for limits on this, which I doubt, or also opinions.

I also realize no matter what the book says, I won’t be driving a rod in the ground for a couple day stay.

 

[Supervstech]

Low voltage arrays are not required to be grounded.

(I think)

In a mobile application, neutral may be floating and not grounded. The array should be bonded to the chassis if it is a metal vehicle and the panels can be in contact with a metal surface. If the roof is fiberglass, and a wood frame, then no bonding is possible or needed.