Solar PV Cable vs Normal Electrical Cable – Why You Can’t Mix Them
Why the Cable Choice Matters in Solar Installations
South Africa’s growing demand for solar energy has made safe, compliant installations more important than ever. While panels, inverters, and batteries often get the spotlight, the cables that connect them are just as critical.
A common mistake in solar installations is using standard electrical cable instead of solar PV cable. At first glance, they may look similar, but they are engineered for very different conditions. Choosing the wrong type not only shortens system life, but also creates fire hazards and insurance risks.
What is Solar PV Cable?
Solar PV cable is specifically designed to handle the unique stresses of solar power systems.
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Flexible, stranded copper conductors for vibration resistance
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Double-layer insulation, typically XLPE (cross-linked polyethylene)
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UV-resistant and weatherproof for outdoor use
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High-temperature tolerance, up to 120°C in some cases
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Resistant to ozone, moisture, and chemical exposure
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Rated for DC voltages (often up to 1,500V)
This makes PV cable durable and safe in harsh South African sun, rain, and dust conditions.
What is Normal Electrical Cable?
Standard electrical cables such as Surfix or Cabtyre are designed for indoor AC applications.
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PVC insulation (suitable for 70°C continuous temperature)
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Limited UV resistance — insulation becomes brittle outdoors
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Not designed for long-term direct sun exposure
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Typically rated for 230V AC, not high-voltage DC
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Intended for fixed domestic wiring or flexible appliance use
These cables work perfectly in their intended environments, but they are not engineered for the demands of solar systems.
Key Differences Between PV Cable and Normal Electrical Cable
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Voltage rating: PV cable is rated for high-voltage DC; normal cable is not
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Durability: PV cable resists UV, weather, and temperature extremes; normal cable degrades quickly outdoors
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Flexibility: PV cable is stranded for flexibility; normal cable is solid or less flexible
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Safety: PV cable insulation prevents DC arcing; normal cable risks insulation breakdown
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Compliance: SANS solar wiring regulations require PV cable for all exposed DC connections
Why You Cannot Mix the Two
Using normal electrical cable in a solar installation may seem like a cost-saving shortcut, but the risks are significant:
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Insulation breakdown under UV exposure
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Overheating due to high DC loads
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Fire hazards from arcing and melted insulation
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Insurance claims rejected due to non-compliance
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Shortened system lifespan and costly repairs
In short: solar requires solar cable.
South African Compliance Requirements
Under SANS 10142-1-2, which covers renewable energy installations:
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All DC cabling must be double insulated
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Outdoor DC cabling must be UV-resistant
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DC cabling must be rated for the maximum system voltage
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Installations must be signed off by a registered person with a CoC
Failure to comply can result in installations being declared unsafe, and insurance will not cover damage caused by non-compliant wiring.
Common Mistakes in Solar Wiring
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Using Surfix or Cabtyre from panels to inverters
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Running normal PVC cable in conduit outdoors, assuming it is protected
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Mixing PV cable and standard cable in the same run
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Undersizing DC cabling, leading to excessive voltage drop
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DIY installations without certification
FAQs
Can I use normal Surfix cable for solar panels?
No. Surfix is not UV resistant and not rated for high-voltage DC.
Is PV cable more expensive than normal cable?
Yes, but it is designed to last 20–25 years outdoors, making it cost-effective in the long run.
Can I use normal cable if I put it in conduit?
No. Even in conduit, non-UV cable insulation degrades in heat and under DC load.
What size PV cable do I need for solar panels?
Most panel strings use 4mm² or 6mm² PV cable, but size must be calculated based on current, distance, and system design.
Is PV cable a legal requirement in South Africa?
Yes. SANS 10142-1-2 requires solar installations to use UV-resistant, DC-rated PV cable.
Can I mix AC electrical cable with DC PV cable?
No. DC and AC circuits must be separated, and each requires cables designed for their purpose.
Buy Solar PV Cable Online with Lite-Glo
At Lite-Glo, we stock a full range of solar PV cables, including 4mm², 6mm², and larger sizes. All cables are UV-resistant, DC-rated, and compliant with South African standards. We also supply connectors, conduit, and accessories to complete your installation.
Shop Solar PV Cable – Per Meter
⚠️ Safety & Compliance Notice
All electrical installations in South Africa must comply with SANS 10142-1 (Wiring Code) and the Occupational Health & Safety Act. Work must be carried out by a qualified, registered electrician.
This article is for general educational purposes only. It does not replace professional advice, and Lite-Glo accepts no liability for how this information is used. Always obtain a valid Certificate of Compliance (CoC) for any electrical work.
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