Solar extension cable 15m 4mm² - red/black for photovoltaic systems (set)

With this solar extension cable set (15 metres, 4mm²) you can also master extensive installations and difficult cable routes. A length of 15 metres gives you enormous freedom: you can place your solar modules where the sunlight is highest (e.g. at the end of the garden or on an outbuilding), while the inverter or battery is safely and securely housed in the house or cellar.

The set consists of two high-quality, double-insulated PV cables (1x red for plus, 1x black for minus). Both cables are already professionally pre-assembled with MC4-compatible plugs and sockets ("Plug & Play"), so you do not need any special tools. The conductor made of tinned copper guarantees good conductivity and corrosion resistance even over this long distance.

Highlights at a glance

• Maximum flexibility: 15 metres in length bridge large distances between the generator field (modules) and the technical room.
• Plug & Play: Ready for immediate use thanks to pre-assembled MC4-compatible plug connectors (male/female).
• Fault protection: The colour set consisting of Red (+) and Black (-) ensures clear assignment of the poles and prevents dangerous polarity reversal.
• Weatherproof & robust: The special insulation made of cross-linked polyolefin is extremely UV-resistant, ozone-resistant and withstands temperatures from -40°C to +90°C.
• Protection class IP67: The connections are dustproof and waterproof in the plugged state (short immersion).
• Certified quality: Meets common standards (e.g. EN 50618) for voltages up to 1500V DC.

Areas of application

The 15-metre extension is ideal for installations with large distances:

• Ground-mounted systems in the garden: When the modules have to be positioned far away from the house to avoid shading.
• Outbuildings: Connecting modules on garage, carport or shed to the main house.
• Complex cable routing: When cables have to be laid around many corners, through empty conduits or shafts and direct routing is not possible.
• Façade systems: For routing the DC cables from high façade positions to the cellar.

Installation & safety instructions

• Consider cable losses: With 15 metres of cable length (30m circuit in total), a physical resistance occurs. For typical PV applications (high voltages with strings or micro-inverters), 4mm² is fine. However, for pure 12V stand-alone systems (charging a battery), the voltage drop would be too high – thicker cables or shorter distances are recommended here.
• Do not wind up cables: Avoid winding excess cable into coils (coil effect/heat build-up). Lay it in loops instead.
• Use protective conduit: When laying in soil or in areas with risk of rodents (attic/garden), a protective conduit (empty/ corrugated conduit) is strictly recommended.
• Strain relief: The high own weight of 15m cable must not be pulled on the small connectors of the solar module. Fix the first section of cable firmly to the module frame.

Properties

FAQs about the solar extension cable 15m

Is a 4mm² cable still efficient at 15 metres?

For grid-connected systems: Yes. If you use the cables for a balcony power system or a roof system (voltage approx. 30-40V or higher), the loss is acceptable (approx. 2-3%). For 12V stand-alone systems: No. If you want to connect a 12V module directly to a battery, the voltage drop at 15m is too high. In this case, use a 6mm² or even better 10mm² cable.

Are the cables suitable for direct burial?

No. The cables are extremely weather-resistant ("underground cable-like"), but are not protected against mechanical damage (stones, spade cut, animal bites). Outdoors on the ground, you should always use a cheap PE pipe or flexible conduit as a protective sheath.

Do the connectors fit my balcony power system?