The underestimated weak point of your PV system
With balcony power plants or your own photovoltaic system, problems often lie in the details: precisely where the solar cables run from the roof into the house. If the cable is simply laid through the tile, it will rub against the sharp clay edge – over the years, the insulation can be damaged. Here are the 5 most common mistakes and how to avoid them.
Mistake 1: Laying the cable unprotected over the tile edge
The classic. Wind moves the cable, and the sharp tile edge acts like a file. A 3D-printed roof penetration serves as abrasion protection: The cable is neatly guided and no longer touches the edge.
Mistake 2: Cutting off the MC4 connectors
Many people cut off the pre-assembled MC4 connectors to get the cable through a narrow hole – and then have to re-crimp them (a real source of errors). Unnecessary: A sufficiently dimensioned penetration allows the cable, including the connector, to pass through.
Mistake 3: Drilling or buying special tiles
You don't need to drill into the roof or buy expensive special tiles. The cables are inserted laterally into the guide slots, and the penetration is simply inserted into the tile – no tools required.
Mistake 4: The wrong material
Cheap, hard plastics embrittle in the sun. On the roof, you need UV and temperature-resistant material. Our penetrations are made of TPU – flexible, weather-resistant, and 3D-printed in Germany.
Mistake 5: Choosing the wrong size
Too small, and the cables won't fit cleanly; too large is unnecessary. The size depends on the number of cables and their cross-section. In our PV roof penetrations, you'll find 105, 125, and 150 mm – for 1 to 4 solar cables plus grounding.
Conclusion: A small part that saves big trouble
The roof penetration costs little but prevents precisely the damage that later becomes expensive: a chafed solar cable on the roof. Pay attention to abrasion protection, the right material (TPU), and the correct size – then your system will remain securely wired in the long term.
Find suitable PV roof penetrations now
More on the topic
- Balcony power plant: Leading solar cables into the house – 3 ways compared
- Solar cables on the roof: Why insulation ages – and how to protect it
- Cutting out roof tiles for PV cable penetration – step by step
Suitable PV roof penetrations from our manufactory: All PV roof penetrations · DIY version without MC4 removal · 125 mm for Frankfurter Pfanne tiles · 150 mm for almost all roof tiles
