What is a PV solar cable?
Solar cables connect photovoltaic modules with inverters and other components of the photovoltaic system. They ensure that the direct current generated in the photovoltaic modules is transmitted. Since they are direct current cables, solar cables are also referred to as DC cables. The transmission of direct current requires special safety requirements. Therefore, solar cables differ from conventional cables used to transmit alternating current. Solar cables have also been used outdoors for decades. They are therefore permanently exposed to weathering and must be UV and weather resistant. In addition to DC solar cables, solar systems also have cables that carry AC power after the inverter to the feed-in meter or into the house. These are usually located in the house and therefore need to be less robust. However, the shortest possible cable lengths are important here.
Requirements for solar cables
Experience has shown that solar cables that do not meet the specified requirements will sooner or later lead to damage and failure of the photovoltaic system. For example, when requesting a quote for a photovoltaic system, make sure that the solar cables meet these standards. When selecting the cable cross-section, make sure that the energy loss is less than one percent. In most cases, cables with a cross-section of 4 mm² should be used. Smaller cross-sections are usually not practical. Since solar cables are constantly exposed to all types of weather, they must meet special requirements. These include good insulation and excellent weather resistance. In addition, the cables should be halogen-free and acid-free. Certification and Tüv testing should also be available from the cables.
What is the structure of a solar cable?
If you remember that solar cables play a minor role in terms of cost compared to all other components of your PV system, it is not worth saving money at this point. Future operators of photovoltaic systems should therefore take special care to use only tested and high-quality solar cables. Tested solar system cables can be recognized by the marking "PV1-F". These have double insulation of the conductor wire. If you want to be absolutely sure that the wiring of your photovoltaic system will last for the next 30 years, look for VDE or TÜV-compliant wiring. These lines are marked accordingly. If you look inside the solar cable, you will see that the copper wires (also called strands) are surrounded by an additional tin sheath on the outside. Long-term tests have shown that cross-linked polymer insulation is more durable than rubber insulation.