[RE-wrenches] Cell damage leading to ground fault?

[David Coale]

I am having the same issue, but it is with an SMA inverter.  In my case it happens when it is raining and clears up when it dries out.  I can see there are some bad cells, but they are right next to the edge of the panel so a moisture problem would show up this way.  Good to know about sealing the conduits.

In your case, you should be able to disconnect the suspected string or jump around the suspected panel and figure this out.  Other wise I would blame it on the squirrels.  But then again, I blame everything on rogue squirrels or rats.

David


> On May 8, 2025, at 12:55 PM, david quattro via RE-wrenches <re-wrenches at lists.re-wrenches.org> wrote:
> 
> Fronius install manual says the conduit entry ports need to be packed with putty around the wires. They’re the only manufacturer I know of that requires this. Water vapor roses into the circuit boards.    I used to get a couple different error codes until we packed the conduits.
>    Good luck, and let us know!
> 
> 
> 
> On Thu, May 8, 2025 at 12:22 PM Dave Tedeyan via RE-wrenches <re-wrenches at lists.re-wrenches.org <mailto:re-wrenches at lists.re-wrenches.org>> wrote:
> Hello, 
> 
> There is an installation that I am servicing with the Q.Peak G4 modules, where one cell has some visible damage. I am wondering whether this type damage can lead to a ground fault? The Fronius inverter on site is picking up an "Insulation Resist" error. I am wondering whether this could be the cause, or whether I should look elsewhere in the array. A photo is attached. Any thoughts would be appreciated.
> 
> Thanks!
> Dave
> 
> -- 
> 
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