Three cable systems in one plant
A ground-mount solar farm and a commercial rooftop use the same logic at different scales. Modules are connected in strings on single-core DC cable rated for sunlight and outdoor temperature. Strings run to combiner boxes or directly to string inverters. Inverter AC output runs at low voltage to a transformer, and on larger plants a medium voltage collection network brings the power to the substation. Alongside the power cable runs control, instrumentation and fibre for monitoring and SCADA. Each system has its own standard and its own drum logic.
| Circuit or section | Cable line | Typical standard | Typical packing |
|---|---|---|---|
| Module strings and string extensions | H1Z2Z2-K 1x4 or 1x6 mm2, red and black sheath | EN 50618, IEC 62930; UL 4703 PV Wire for US | 100 m coils, 500 m drums |
| Combiner to inverter DC feeders | Larger PV cable sizes or DC cable per design | EN 50618 / IEC 62930 within the plant's range | Drums per run |
| Inverter AC output to transformer | Aluminium XLPE cable or copper LV XLPE | IEC 60502-1 | Drums, length per run |
| Buried AC runs across the site | Armoured cable, STA or SWA | IEC 60502-1; BS 5467 / BS 6724 where specified | Steel-wood or steel drums |
| MV collection to the substation | MV XLPE cable, copper or aluminium | IEC 60502-2; partial discharge to IEC 60885-3 | Heavy drums, one or more runs each |
| Weather station, tracker and SCADA | Instrumentation cable; outdoor loose tube fibre | Per specification; Telcordia GR-20 for fibre | Drums; 2 km / 4 km fibre drums |
The reference PV construction is H1Z2Z2-K 1x4 mm2 from a partner plant catalogue: tinned flexible copper Class 5 with single wires of 0.31 mm or less, 0.7 mm cross-linked halogen-free insulation, 0.8 mm cross-linked halogen-free sheath, overall diameter 5.7 mm plus or minus 0.2 mm, rated DC 1.5 kV, with maximum conductor resistance of 5.09 ohm/km. Public datasheets put 1x4 at about 55-66 kg/km and 1x6 at about 75-86 kg/km.
Standards and market notes
EN 50618 and IEC 62930 define the current generation of PV cable; the older PV1-F designation has been replaced by H1Z2Z2-K, so a quote still offering PV1-F should be questioned. US projects use PV Wire to UL 4703 at 600, 1000 or 2000 V, and usually require UL or other NRTL listed products to satisfy the AHJ. A TUV certificate or UL listing belongs to the partner plant and the specific construction; the desk checks it in the certifier's public database per order. AC and MV cables follow IEC 60502-1 and IEC 60502-2 or national equivalents. Conductor sizes on DC and AC circuits are set by the designer from voltage drop, installation method and grouping, never from a supplier table. See EN 50618 solar cable.
Where the cable comes from
New-energy cable is a strength of Ningjin in Hebei, a cluster of 2,393 firms with 68.89 billion yuan of revenue in 2024, up 28.9% (Hebei industry department, 2025), and recognised as a medium and low voltage and new-energy cable cluster. MV and armoured cable for the collection network often comes from Yixing and Guanlin in Jiangsu. Fibre for SCADA comes from the fibre clusters. One project can involve three partner plants.
Drum planning for a PV site
String cable volumes are large but runs are short, so PV cable usually ships in 100 m coils or 500 m drums split by colour, which keeps red and black stock balanced across the blocks. AC and MV cables are the opposite: fewer, longer runs that should be pulled without joints, so the drum plan follows the cable schedule run by run and the drum weight follows what the site's equipment can lift. Open sites leave drums in sun and rain for weeks; specify lagging and sealed end caps, and see packaging and drums.
Typical risks on solar projects
- Superseded or unlisted constructions. PV1-F offered as if current, or a certificate that covers a different size range.
- Conductor and tinning shortfalls. Resistance above 5.09 ohm/km on 4 mm2 tinned Class 5 means less copper than declared.
- Colour imbalance. Red and black ordered in equal metres when the layout needs a different split.
- Aluminium terminations. Aluminium AC cable needs lugs and procedures suited to aluminium; confirm with the installer before switching from copper.
- Drum damage in storage. Unprotected drums lose sheath integrity at the outer turns.
MOQ and lead time follow MOQ and lead time and are confirmed in writing per order. Send the string layout and cable schedule through the quote form.