PV Cable in South Africa: What Is Allowed, What Is Not, and Where Each Type Applies

One of the most common disputes on solar installation projects in South Africa is PV cable — specifically, what type is legally required, where it must be used, and when a cheaper alternative is permissible. The question comes up constantly among electricians, contractors, and procurement teams: do I really need H1Z2Z2-K throughout, or can I use SWA for some of the run?

The answer depends entirely on where in the system the cable is installed. Here is a clear breakdown based on IEC 60364-7-712 (the international standard for PV power supply systems) and IEC 62930 (the standard governing PV cable specifications).

Why PV DC Cable Has Its Own Standard

Standard electrical cables — even high-quality SWA XLPE — are not designed for the specific conditions found in a solar DC system. PV cables must withstand:

• Continuous UV exposure for 25+ years without degradation
• High operating temperatures (cables on rooftops or ground arrays routinely exceed 70°C surface temperature)
• Mechanical flexing from wind movement, tracker systems, and handling
• DC voltage up to 1500 V, which behaves differently from AC in terms of arc fault risk
• Long-term moisture and ozone resistance

Standard PVC or XLPE cables are not rated for these conditions in exposed outdoor DC applications. IEC 62930 exists specifically to define the cable construction and testing requirements for PV use — and IEC 60364-7-712 tells you where that standard applies in your system.

The Cable That Meets the Standard: H1Z2Z2-K

H1Z2Z2-K is the designation for PV-compliant DC cable under IEC 62930. The designation tells you exactly what it is: a single-core, flexible, halogen-free cable with a cross-linked polyolefin insulation and outer sheath, rated to 1.5 kV DC and tested for UV resistance, heat ageing, and outdoor exposure. It is available in both Class 2 (solid/stranded) and Class 5 (flexible fine-strand) conductor options.

Where IEC 60364-7-712 mandates PV-specific cable, H1Z2Z2-K is what satisfies that requirement.

Where H1Z2Z2-K Is Mandatory

The standard is clear: anywhere the DC cable is exposed — to UV, to heat build-up, or to mechanical movement — you must use IEC 62930-compliant cable. In practical terms, this covers:

• Module to module (inter-module) connections: The short flexible cables linking panels on a string. Full UV and heat exposure. H1Z2Z2-K is mandatory — no exceptions.
• Module to string combiner or DC distribution unit: The string cables running from panels along the mounting frame to the combiner box or first point of consolidation. Exposed, often flexing, fitted with MC4 connectors. Must be H1Z2Z2-K.
• String combiner to array junction box (where used): Still on the array, still exposed. IEC 62930-compliant cable required here too.

The logic is straightforward: if the cable is in the array, on the frame, or anywhere it sees sunlight and outdoor conditions, it must meet the PV cable standard. Using standard SWA or PVC cable in these positions is non-compliant, full stop.

Where SWA and Other DC-Rated Cables Are Permitted

IEC 60364-7-712 includes an important “or” clause: where a cable is not exposed — because it is buried underground, installed inside conduit, or run inside trunking or a building — it is not required to meet IEC 62930, provided it is suitable for DC application and rated at or above the system voltage.

This opens up the use of SWA XLPE/PVC or LSZH cables in the following positions:

• Array junction box to DC isolator or distribution board: If this run is buried or in conduit with a minimum impact protection rating of 750 N per IEC 61386-24, DC-rated SWA is permitted. The armour in this context is treated as a protective earth — not as a live DC conductor.
• DC isolator to inverter DC terminals: If this section is indoors, in trunking, or mechanically protected, both H1Z2Z2-K and DC-rated SWA are permissible. Choose based on the environment.
• Inverter DC bus to battery (hybrid and BESS systems): This is typically an indoor run with no UV exposure. Class 2 DC-rated SWA is acceptable here. Flexible Class 5 battery interconnect cables are used for the short connections between battery cells or modules.

The key test is simple: is the cable exposed or protected? Exposed means H1Z2Z2-K. Protected means DC-rated SWA is allowed — but it still must be rated at or above the system DC voltage, which for most modern systems means 1000 V or 1500 V.

What Is Never Allowed on the DC Side

• Standard 600/1000 V AC SWA used in exposed PV cable positions — not rated for DC at system voltage, not UV-tested
• PVC-insulated single-core cable in exposed outdoor runs — UV degradation over time is a documented failure mode
• Any cable with an insulation voltage rating below the system DC voltage
• Using the steel armour of SWA as a DC live conductor — armour is earth only
• Running DC and AC cables in the same trunking or conduit without segregation — IEC 60364-7-712 requires DC/AC separation

The AC Side Is Different

Once you are past the inverter output on the AC side, ordinary installation rules apply. Standard 600/1000 V SWA cable per SANS 10142-1 and IEC 60364-5-52 is perfectly correct for the AC wiring from the inverter to the distribution board and beyond. The PV-specific cable requirements do not extend to the AC side of the system.

A Quick Reference Summary

Array and string cables (exposed): H1Z2Z2-K per IEC 62930 — mandatory.
Buried or conduit-protected DC runs: DC-rated SWA at system voltage — permitted under the “or” clause of IEC 60364-7-712.
Indoors, no UV (inverter to battery, etc.): DC-rated SWA or H1Z2Z2-K — both acceptable.
AC side from inverter onwards: Standard SWA per SANS 10142-1 — ordinary wiring rules apply.

Supplying the Right PV Cable for Your Project

Green Dawn Electric supplies H1Z2Z2-K PV cable and DC-rated SWA cable for solar projects across South Africa. Whether you are specifying cable for a residential string system, a commercial rooftop array, or a large ground mount installation, we can supply the correct cable type for each section of your system — and help you avoid the compliance issues that come from using the wrong product in the wrong position.

We supply. You install. Contact us to discuss your project cable requirements and get a quote.