Almot wrote:
The only situation where you could damage the ceiling wires, is drilling a big hole for thick cables of the roof junction box.
As someone who
has damaged wires (and other things) by drilling, I now use a
hole saw which allows you to go through the roof one layer at a time so you can check what you're drilling into.
Almot wrote:
If you have to do parallel wiring, you should (and could) try and avoid such a box.
Yes, those plastic combiner boxes have a way of breaking down in direct sunlight. So I switched to sat TV roof plates which I could install
under a PV panel -- so no direct sunlight:
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Almot wrote:
Run a short MC4 gauge 8 through the fridge vent and install the J-box in a closet next to the fridge.
Running my PV panel wires through the fridge vent wasn't a good option for me as it would have almost doubled the length of my wire run and increased voltage drop.
My parallel run was a direct path through the roof to a breaker box > controller > batteries.