Solar extension cable 45m 4mm² - red/black for optimum PV connections (set)

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

The set includes two high-quality, double-insulated solar cables: one red cable for the positive pole (+) and one black cable for the negative pole (−). Both ends are professionally pre-assembled with MC4-compatible connectors and sockets. Due to the considerable length of 45 metres (90 metres total current path), this set is primarily intended for systems with high string voltage, to keep percentage line losses within reasonable limits.

Highlights at a glance

• Extreme range: With a length of 45 metres per cable, you can also realise complex installation scenarios far from the house connection or main distribution board.
• Plug & Play installation: The cables are pre-assembled on both sides with MC4-compatible connectors, so no special crimping tool is required.
• Secure identification: Clear colour coding in red (+) and black (−) effectively prevents dangerous mix-ups of polarity during very long cable runs.
• Weatherproof & Durable: The special sheath made of cross-linked polyolefin is UV-resistant, ozone-resistant and can withstand extreme temperatures from −40°C to +90°C.
• Protection rating IP67: The connectors are absolutely dust-tight when plugged in and protected against temporary submersion (e.g. during heavy rain or puddle formation).
• High quality conductor: Tinned electrolytic copper provides maximum corrosion resistance and permanently excellent conductivity.

Areas of application

This 45-metre extension is intended for specific scenarios:

• Large ground-mounted systems
  • Ideal for placing modules far away in the garden or on a field, where there is no shading from buildings or tall trees.
• Outbuildings & Agriculture
  • Connecting distant garages, carports, sheds or barns to the main building.
• Indirect cable routing
  • When cables cannot be laid directly but instead have to be routed all around the house or through widely branched empty conduit systems.

Installation & safety instructions

• Voltage drop (Important!)
  • With 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 stand-alone systems, this cable is absolutely unsuitable due to the massive voltage loss; here you would have to use cross-sections of 16mm² or more.
• Laying in the ground
  • Although the cable is weatherproof, it is not protected against mechanical influences (spade cuts, rodents). When laying underground, always use a protective conduit (e.g. flexible conduit or cable protection pipe).
• Avoid induction & heat
  • Never coil excess cable into a tight spool while current is flowing, as this can lead to induction and heat build-up. Lay excess cable in wide loops ("meanders").

Features

FAQs about the solar extension cable 45m

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

Technically safe for high-voltage systems, but critical for efficiency. With a typical plug-in solar system (approx. 40V module voltage, 10A current), you have a voltage drop of approx. 4 volts at 45m. This means around 10% power loss. This is technically safe, but no longer recommended. To optimise the yield with this extreme length, you should definitely upgrade to 6mm² or even 10mm² cable.

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

Yes. The connectors used conform to the global MC4 standard, which is used with almost all modern solar modules and micro inverters. They fit perfectly in terms of both mechanics and electrics.

Can I shorten the cable if necessary?