Solar extension cable

The Solar extension cable set (45 metres, 4 mm²) is the specialist solution for photovoltaic projects involving extreme distances. If your solar panels need to be positioned in the sunniest spot on your property – for example, at the far end of a very large garden, on a distant barn or in an open field – and the inverter is to remain centrally located in the house, this kit allows you to bridge the distance safely and reliably.

The set includes two high-quality, double-insulated solar cables: a red cable for the positive terminal (+) and a black cable for the negative terminal (-). Both ends are professionally pre-terminated with MC4-compatible plugs and sockets. Due to the considerable length of 45 metres (90 metres total circuit length), this set is primarily designed for systems with high string voltage, in order to keep the percentage of line losses within acceptable limits.

Highlights at a glance

• Extreme range: With a length of 45 metres per cable, you can also implement complex installation scenarios far away from the domestic connection or main distribution board.
• Plug & Play installation: The cables are pre-fitted with MC4-compatible connectors at both ends, so no special crimping tools are required.
• Reliable identification: The clear colour-coding in red (+) and black (-) effectively prevents dangerous polarity mix-ups over this very long installation run.
• Weatherproof & durable: The special cross-linked polyolefin sheath is UV-resistant, ozone-resistant and withstands extreme temperatures ranging from -40°C to +90°C.
• IP67 protection rating: When connected, the connectors are completely dust-tight and protected against temporary submersion (e.g. during heavy rain or when puddles form).
• High-quality conductor: Tinned electrolytic copper ensures maximum corrosion resistance and consistently excellent conductivity.

Areas of application

This 45-metre extension is intended for specific scenarios:

• Large ground-mounted systems
  • Ideal for installing modules far away in the garden or in a field, where there is no shade cast by buildings or tall trees.
• Outbuildings & Agriculture
  • Connecting garages, carports, sheds or stables located some distance away from the main building.
• Indirect cable routing
  • If cables cannot be laid directly, but have to be routed around the entire house or through extensive conduit systems.

Installation & Safety Instructions

• Voltage drop (Important!)
  • At a length of 45 metres, the total current path is 90 metres. For grid-connected systems with high string voltage (> 150V), 4mm² is still acceptable. For 12V or 24V off-grid systems, this cable is completely unsuitable due to the massive voltage drop; cross-sections of 16mm² or more would need to be used in such cases.
• Laying in the ground
  • Although the cable is weatherproof, it is not protected against mechanical damage (such as being cut by a spade or damage caused by rodents). When laying the cable underground, you must use a protective conduit (e.g. flexible conduit or cable protection conduit).
• Avoid induction and heat
  • Never wind excess cable into a tight coil whilst electricity is flowing, as this can lead to induction and the build-up of heat. Lay any excess length in loose loops ("meandering").

Features

FAQs on the 45m solar extension cable

Is 4 mm² really still sufficient for a length of 45 metres?

Technically safe for high-voltage systems, but critical in terms of efficiency. With a typical balcony solar system (approx. 40V module voltage, 10A current), you will experience a voltage drop of approx. 4 volts over a distance of 45 metres. This corresponds to a power loss of around 10%. Whilst this is technically safe, it is no longer recommended. Anyone wishing to optimise their yield should definitely opt for 6 mm² or even 10 mm² cable.

Will the connectors fit my inverter from Hoymiles, Deye or Growatt?

Yes. The connectors fitted comply with the global MC4 standard, which is used in almost all modern solar panels and micro-inverters. They fit perfectly, both mechanically and electrically.

Can I shorten the cable if necessary?