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 challenging cable routes. A length of 15 metres gives you enormous freedom: you can place your solar modules where solar irradiation is highest (e.g. at the end of the garden or on an outbuilding), while the inverter or the battery is safely housed indoors or in the basement.

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

Highlights at a glance

• Maximum flexibility: 15 metres of cable length bridge large distances between the generator field (modules) and the technical room.
• Plug & Play: Ready for immediate use thanks to pre-installed MC4-compatible plug connectors (male/female).
• Fault protection: The colour set consisting of Red (+) and Black (-) ensures a 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.
• IP67 protection class: The connections are dustproof and water-resistant (short-term immersion) when plugged in.
• 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 long distances:

• Ground-mounted systems in the garden: If the modules have to be located far from the house to avoid shading.
• Outbuildings: Connecting modules on the garage, carport or shed to the main building.
• Complex cable routing: When cables need to go round many corners, through empty pipes or shafts and a "direct line" is not possible.
• Facade systems: For conducting the DC lines from high facade positions to the basement.

Installation & safety instructions

• Note line losses: At a cable length of 15 metres (total 30 m circuit) a physical resistance is created. For typical PV applications (high voltages for strings or micro-inverters), 4mm² is fine. However, in pure 12V stand-alone systems (charging a battery), the voltage drop would be too high — here thicker cables or shorter runs should be selected.
• Do not coil cables: Avoid winding excess cables into rings (coil effect/heat development). Rather, lay it in loops.
• Use protective tubing: When laying in the ground or in areas with the risk of rodents (attic/garden), a protective tube (empty tube/corrugated tube) is strongly recommended.
• Strain relief: The high weight of 15m of cable must not pull on the small connectors of the solar module. Secure the first section of cable tightly to the module frame.

Features

FAQs about the 15m solar extension cable

Is a 4mm² cable still efficient at 15 metres in length?

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

Are the cables suitable for direct burial?

No. Although the cables are extremely weather-resistant ("like earth cables"), they are not protected against mechanical damage (stones, spade cut, animal bites). Outdoors at ground level, you should always use an inexpensive PE pipe or flexible conduit as a protective sheath.

Do the connectors fit my balcony system?