Solar Cables

What is a solar cable?

Solar cables are UV-resistant DC cables used to connect solar panels to each other, to a charge controller or to inverters. Thanks to their insulation, which is resistant to sunlight (UV), high and low temperatures and moisture, they can be used for many years in rooftop and ground-mounted installations. Standard indoor wiring cables may not withstand these conditions outdoors; therefore, solar cables must be used for panel connections.

How is the cable cross-section selected?

Cable cross-section is selected according to the current to be carried and the cable length. In DC systems — especially in low-voltage (12–24 V) applications — voltage drop increases rapidly over long cable runs, leading to energy loss and improper operation of devices. The 4 mm² cable in this category is a cross-section widely used in many panel connections. For high-current or long-distance runs, a larger cross-section may be required.

Installation recommendations

• MC4 connectors must be used at cable ends and crimped with the appropriate tool.
• Positive and negative cables must be marked with color or labels.
• Cables must be secured so they do not rub against sharp edges, remain slack-free, and cannot be blown about by the wind.
• Cables routed underground must be laid inside a protective conduit.
• Appropriate fuses and disconnects must be used between the panel array and the controller.

Safety

Solar panels generate voltage as long as they receive light; panels should be covered or the system shut down before making cable connections. If the cable insulation shows damage, cracks, or crushing, the affected section must be replaced. Having the connections inspected by a qualified electrician ensures long-term safety.

Frequently asked questions

Can regular cable be used in a solar panel system?

It is not recommended, as regular cable is not resistant to UV radiation and outdoor weather conditions.

Is 4 mm² cable sufficient?

It is sufficient for many small and medium systems; as current and distance increase, a larger cross-section may be required.

How long should the cable be?

It should be as short as possible — no longer than the distance from the panel to the controller.

Can I bury the cable underground?

It is recommended to lay it inside a protective conduit at an appropriate depth.

Why does voltage drop matter?

Voltage drop means energy loss and negatively affects battery charging.

Are connectors purchased separately?

Yes; connectors are available separately in the category.

Is solar cable the same as inverter cable?

UV-resistant solar cable is used on the panel side; between the battery and the variable frequency drive (VFD), thicker cables suitable for high current are preferred.