I already have been using the PVC Electrical boxes from Lowes and going through the side of the roof into ceiling mounted cabinets for my Ham Radio antenna wiring.
I don't have solar panels yet but will most likely follow this idea with the required cables...
Using the PVC electrical boxes on both sides of the wall and cut a large hole thru the center of each box. Then you can glue in a PVC short pipe to connect the two boxes and seal up good all around it... Never been a problem doing this for my Ham Radio antennas extending above the roof.
I have used this idea as well inside the floor mounted cabinets where alot of wiring is put in going to the underside of the trailer... Makes for a great loop around the the floor of my trailer for wiring. All protected inside PVC lines and electrical boxes with sealed lids...
These kind of PVC Electrical Boxes come in all sizes and many different combinations of ports.
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Roy Ken
