Portable solar panel junction box repair
3D-printed junction box and charge controller mount for the Allpowers 100 W foldable solar panel
On many foldable solar panels the factory junction box is glued over the spot-welded busbars, so a loose or burnt cable can’t be reached or fixed. We remove the old box, slide a printed frame in under the panel’s outer textile layer around the contacts, and screw a cover on top through the textile, so the contacts stay reachable. The upgrade version swaps the cover for an adapter that carries a solar charge controller, so the panel can charge a 12 V battery directly. Drag the model to rotate it, scroll or pinch to zoom.
Gallery
Print it
| Material | PETG (handles sun and heat better than PLA) |
|---|---|
| Print time | ≈ 2 h for frame and cover |
| Layer height | 0.2 mm |
| Walls / infill | 3 perimeters, 20–30 % infill |
| Nozzle / bed | 235–245 °C / 75–85 °C |
| Supports | None, print every part flat |
| Size | Junction box 120 × 120 × 20 mm; with controller adapter 140 × 120 × 25 mm |
| Panel | Allpowers 100 W foldable solar panel |
| Files | solarbase.stl, solarcover.stl, Solarchargercontorler-Fusion.stl and two FreeCAD files |
These are our recommended settings; the download pages list the files but no fixed profile.
What you need
Frame (solarbase) slides in under the outer textile layer around the contacts. Cover (solarcover) closes it with 8 × M3 screws. For the upgrade, the controller adapter replaces the cover and holds the charge controller with 4 × M4 screws on a 128 × 70 mm hole pattern. You also need a sharp knife, solder, and a 12 V solar charge controller that fits that hole pattern.
Edit it
The FreeCAD files have every body, so you can change the frame size or the hole pattern for your own panel or controller.
Need it fixed for you?
We can print the parts, or repair and upgrade your panel in Sarajevo. Message us for price and delivery, or send a quote request.
Repair & upgrade
- Printed frame + cover
- 8 × M3 screws
- Sharp knife
- Solder & flux
- 12 V LCD solar charge controller (optional)
- 4 × M4 screws (optional)
- Remove the factory boxCut and peel the glued junction box off the back of the panel without bending the busbars underneath.
- Fix the contactsClean the spot-welded busbars, re-solder the cable cores and check the bypass diode, so the panel delivers its full voltage again.
- Slide the frame under the textileCut the outer textile layer open over the contacts and slide the printed frame in underneath it, so the textile holds the frame against the panel. The low sides leave a slot for the cable.
- Close itPut a foam pad into the frame, set the cover on top of the textile and screw it through the textile into the frame with 8 × M3 screws. If anything fails later, unscrew the cover and the contacts are right there.
- Upgrade: add a charge controllerInstead of the cover, screw on the controller adapter, mount the charge controller with 4 × M4 screws and connect the panel to the SOLAR terminals.
- Connect and testConnect the battery to the BATTERY terminals, put the panel in the sun and check the voltage on the controller’s display.
The charge controller, busbars, diode and cables in the 3D model and renders are drawn for illustration; they are not in the download. Working on solar panels and batteries carries electrical risk. Do it at your own risk; PrintYourFix is not responsible for damage.
Credits
“Portable solar panel junction box fix repair upgrade” by PrintYourFix, licensed CC BY-SA. See the Thingiverse listing. Allpowers is a trademark of its owner; this part is an independent repair design, not made or endorsed by Allpowers.