Solar Panels on an Aluminum Boat

[Namoian]

Just got a quote on a solar panel package (4 Kyocera panels, Blue Sky controller, etc.) and it included an item labeled "grounding assembly". This is a bolt secured through the aluminum edge of the solar panel to make sure the panel has a good ground connection to the boat. Does anyone know if this is just a safety issue or whether there may really be current flowing through this ground thus creating an electrolysis risk?

[s/v Jedi]

I would not do that so quickly on an aluminium boat!

I can think of two or three reasons for grounding the panels:

- exposed metal so connect to your AC ground (which isn't the hull for you)
- lightning strike (don't think it will make any difference grounded or not)
- static charge... well may be... but not on my boat so no.

I wonder what reason the manufacturer gives for this ground connection.

cheers,
Nick.

[espresso]

I have just fitted solar panels to my Ally boat.
When you say that the edge of the panel is grounded to the boat, do you mean that the negative is connected to the boat, or is just the glass encapsulating the panel connected to the boat?

[s/v Jedi]

No, the metal (aluminium) frame of the panels is connected to the boat.

cheers,
Nick.

[foolishsailor]

I have 3 85 watt kyocera panels on my boat.

I was not aware there was any grounding effect by attaching bolts through the aluminum frame on the panel. I have my three panels bolted through the aluminum frame directly to my aluminum davits. The bolts are insulated with teflon sleeves from both the davits and the frame on the panels, but the panels are in direct contact with the davits.

I see no pitting or peeling paint - but that does not mean it is not there

My understanding of the frames is that there is glass (or equivilent) on top of the silicon and therefore non-conductive and there is a wheatherproof backing on the bottom (non-conductive) and a rubber gasket holding it all in the frame - also non-conductive.

IMO if you are running a two wire system on your boat and not running any grounds you should not have a problem.

I am in no way an expert but after looking closely at the panels I dont understnad how bolting the frame to your boat would in any way consitute a ground.

Please if any one knows otherwise I would like to know as well so I can kick myself and redo my installation!

[espresso]

My panels are attached to the roof of my pilothouse. I have made no attempt to isolate the frames from the boat because they are both Aluminium.

[Namoian]

Thanks for all the input. As I now understand it, the grounding (of the aluminum frame of the panels) is a National Electric Code (NEC) requirement, probably to protect against the accidental electrification of the panels from a stray wire. So not an issue on a boat (I hope) and not a concern for electrolysis.

[s/v Jedi]

Yes, the last three posts are all correct: there is no electric connection between the cells and the frame.

I have never noticed a static charge so that isn't the problem so it is just about a piece of metal that they want to ground in case some idiot decides to electrify it ;-)

@espresso: but do like foolishsailor and isolate the fasteners, right? ;-)

ciao!
Nick.