Solar panel earthing

Does each solar panel need to be connected individually to the ground wire or since each panel is bolted/touching the aluminium mounting structure, can the ground wire be connected to just one point on the mounting structure.

I’m not sure what our local regulations say. But the Pv-modules have a hole for mounting an earth lug, so it does appear they want you to individually earth them. Common practice is to earth the whole structure, and then to daisy-chain the earth lugs on the modules and attach that to the same mounting point where the structure is earthed.

Would the hole per frame not be in the event you buy just one?

Question: Cause I’m now wondering, if you mount the panel frame onto the rails, would that not be a better “connection” for earthing each panel, and then earthing the entire frame once?

Again, looking at what is on the market, the issue appears to be that the anodising of the aluminium prevents a good connection. To deal with that, you get earthing clips and screws that actually bite into the aluminium to get a good connection, and if you used those as directed, then you could in theory earth the modules to the frame and then simply earth the frame.

This is one of those issues where everyone likely has a different answer. If you want to provide the one true answer that nobody will argue isn’t good enough (but several people may argue is overkill), then you earth them individually :slight_smile:

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If you want to start a argument bigger than Victron vs … or Toyota vs Ford, then walk in to a bar full of electronic and electrical guys and bring up the topic of earthing. There’s AC, there’s DC, then there’s also earthing vs grounding, earthing for safety, earthing for static, earthing for lightning.

I’m a radio amateur, I’m tired of research on the topic and I still don’t quite understand it. Basically legal and other codes of good practice aside there is no right or wrong way.

Soos hulle se, elke man soen sy vrou op sy eie manier.

It used to be Toyota vs Isuzu. How the times have changed. All I know is, don’t park your Ranger right below your bedroom window. It’s going to wake you up tonight when it breaks down…

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I have taken 1 earth wire up and I loop it from panel to panel through the provided holes and then to the frame. Honestly, it doesn’t take that much more effort. Rather safe than sorry is what I though, overkill won’t kill anything.

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When the panels were destined to be wired into MPPT, I would just rely on frame roof contact.
When the panels were destined for a higher voltage transformerless PV inverter I would go with dedicated earth wires.

Then I discovered that as my installation grew I reconfigured and repurposed arrays a lot, so now all future panels will have dedicated earth wires so I can be flexible.

I could not find anything in any regulation yet that tells me every panel needs to be earthed individually.

In sans the ohm reading to a open touchable metal part should be below a certain value. When we test our installation before we hand over we also test the reading to the panels. We earth every rail and depending on the size of the array we would inter connect the rails at different intervals to strengthen the earth.

For panels mounted on a metal roof, we test earth to the roof first to ensure that the structure is properly earthed, we then add earth wires to 1 or more of the mounting feet on each row of panels.


And the Winner of the topic is… @JacoDeJongh

Yes, you need to earth AND bond the modules, however, if you break the anodising as noted via the frame/bolting/clamps then you do not need each earth module jumper wire thing.

But you NEED to test and then if you are in Jhb vs Cpt then you need a lightning risk assessment and it might end up that you need some additional earthing/down conductor.

Had a few training courses on this and yes, you have varying opinions but only one way to do it correctly!

Ditsem, measure, measure, measure…

The K2 mounting system that I use have clips like these:

They bite into the aluminium of the panel frame, thus bonding it to the rail. Then you simply ground the rails. Quick and easy.

I use these. Your panels are then grounded on 4 points to the rails.

I also use them. Extreamly easy to work with and very sturdy when mounted.

And very, very, very… tough to get off when you don’t have the correct gadget :scream:


That is a good thing :smiley:

It is and if you get the anti-theft version - NO CHANCE!!!

What happens if you got the anti-theft version and you want to move a panel?

You have to buy the gadget (tool) - not cheap!

Must be honest, I was hoping you were going to tell me, have to cut the clamp off or something.

The moment you have an anti-anti-theft device, it is not an anti-theft solution anymore, methinks.

Yes you are making it more cumbersome for the opportunistic thieves, but still, methinks that ideally, one wants to make it near impossible to remove once fitted.