Application note
Waterproof Roof Cable Entry on a Camper
When the cable assembly of solar panels on the roof of a camper is run, the practical route is to bring the cable through the roof penetration into the interior rather than around the outside of the vehicle.
The Challenge
A cable passed through a drilled hole and sealed by hand is not splash-proof for long, has no strain relief, and gives the cable nothing to bear against but the raw edge of the hole.
Pain Points
- A hand-sealed hole loses its seal as the roof flexes and heats
- No strain relief means road vibration is carried straight into the cable entry
- Water tracking down the cable into the roof void goes unnoticed until damage appears
- A second cable usually means a second hole and a second seal to maintain
What We Recommended
Step 1
Drill a sufficiently large hole in the roof and bond the entry housing over it with the adhesive supplied for the purpose.
Step 2
Use the double-hole box where two cables have to cross the roof line — each launch carries an 11 mm thick cable.
Step 3
The PG 13.5 gland size provides the strain relief that protects the cable from mechanical stress.
Step 4
Where only one launch is needed, close the second with the supplied cap.
Result
What Changed
The cable entry into the vehicle is splash-proof once the housing is bonded
Strain relief at the gland protects the cable from mechanical stress
Any other cable can be routed the same way — antenna cable, for example, not only solar cable
One penetration instead of two when both array legs share the box
Products used
Hardware Referenced in This Note
BS090025-BSolar Cable Entry Double Hole Black
Two IP65 glands in one bonded box — one roof penetration for both legs of an array.
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BS090025-WSolar Cable Entry Double Hole White
The white twin-gland roof box for caravan, motorhome and RV solar roofs.
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BS090028-BSolar Cable Entry Single Hole Black
A bonded waterproof gland housing that takes one 6–12 mm solar cable through a roof or deck without a leak path.
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BS090028-WSolar Cable Entry Single Hole White
The white single-gland roof feed-through — recyclable ABS, UV resistant, and half the weight of a metal equivalent.
View details →Questions
Frequently Asked Questions
How thick a cable will each launch take?
Each of the two launches can carry one cable up to 11 mm thick.
What provides the strain relief?
The PG 13.5 gland size provides strain relief, which protects the cable from mechanical stresses.
Can I run something other than solar cable through it?
Yes. Any other cable can be drawn through — antenna cable, for example — through the roof penetration into the interior of the motorhome.
What if I only need one of the two launches?
Close the second with the supplied cap.
A Similar Job to Quote?
Describe the vehicle or vessel, the panels and the roof construction. We will tell you what to order and what to bond it with.