To buy power cable from China, specify the voltage rating, conductor material and size, insulation type, armour and fire performance, require compliance with IEC 60502, and verify conductor resistance on delivered drums before acceptance. Cable is sold by length and weight, so the most common quality failure is a conductor that looks correct but contains less metal than the size on the sheath claims.
This guide explains the main choices, the documents to request and the checks that protect you after delivery.
LV and MV cable: where the line falls
IEC 60502 is the core standard for extruded-insulation power cables. Part 1 covers cables rated 1 kV and 3 kV (low voltage), and Part 2 covers cables from 6 kV up to 30 kV (medium voltage). Above that range, buyers move to high-voltage cables under different standards.
Cable voltage is written as Uo/U, for example 0.6/1 kV or 12/20 kV. Uo is the voltage between conductor and earth or screen; U is the voltage between phases. Make sure the Uo/U rating matches your system voltage and earthing arrangement.
For the ranked list of Chinese manufacturers, see power cables.
XLPE vs PVC insulation
| Property | XLPE (cross-linked polyethylene) | PVC (polyvinyl chloride) |
|---|---|---|
| Maximum conductor temperature, continuous | 90 °C | 70 °C |
| Short-circuit temperature limit | 250 °C | 160 °C (smaller sizes) |
| Current-carrying capacity | Higher for the same size | Lower |
| Dielectric losses | Low, suitable for MV | Higher, used mainly for LV |
| Fire behaviour | Does not contain halogens | Contains chlorine; emits acid gas when burning |
| Typical use | LV and all MV cables | LV building and distribution cables |
For MV cables, XLPE is the normal choice. For LV, XLPE gives more ampacity per size, which can allow a smaller conductor; PVC remains common for general LV wiring and building wires.
Copper vs aluminium conductors
Copper has lower resistance, so a copper cable carries more current for the same cross-section and is easier to terminate. Aluminium is lighter and usually cheaper per ampere, but needs a larger size for the same current and correct lugs and connectors to prevent joint problems.
- Use copper where space is tight, terminations are frequent, or the cable runs inside panels.
- Use aluminium for long feeders, larger sizes and overhead or underground distribution where weight and cost matter.
- Consider aluminium-alloy cables where local codes accept them and flexibility is needed.
Whatever the material, specify the conductor class under IEC 60228: class 1 is solid, class 2 is stranded, and class 5 is flexible.
Armoured or unarmoured
Armour protects cable laid directly in the ground or in areas with mechanical risk.
- Steel wire armour (SWA) is used on multi-core cables for direct burial and high tensile loads.
- Steel tape armour (STA) gives crush protection but less tensile strength.
- Aluminium wire armour (AWA) is used on single-core cables, because steel armour on single-core AC cable causes induced currents and heating.
See the ranked list of armoured cables for suppliers in this group.
Flame-retardant and low-smoke cable
Fire performance matters in buildings, tunnels, plants and anywhere people need to escape. Name the test standards rather than marketing terms:
- IEC 60332-1 — flame propagation test on a single cable.
- IEC 60332-3 — flame spread on bunched cables, with categories by the amount of material tested.
- IEC 61034 — smoke density during burning.
- IEC 60754 — acid and corrosive gas emission (halogen content).
A low-smoke zero-halogen (LSZH) cable should have test evidence for all of these. For circuits that must keep working during a fire, look at mineral-insulated cables or fire-resistant designs. The ranked list of flame-retardant cables covers the wider group.
Specification checklist for your enquiry
- Standard: IEC 60502-1 or IEC 60502-2 (or the local standard required).
- Voltage rating Uo/U and system earthing.
- Number of cores and cross-section, for example 4 × 95 mm².
- Conductor material and class (IEC 60228).
- Insulation (XLPE or PVC) and, for MV, screen type and cross-section.
- Armour type and outer sheath material and colour.
- Fire performance tests required.
- Drum lengths, tolerance on length, and drum type.
- Sheath marking: manufacturer, size, voltage, standard, year and metre marking.
- Type-test report, routine tests and witness or third-party inspection.
Conductor resistance: the check that matters most
IEC 60228 sets the maximum DC resistance per kilometre at 20 °C for each conductor size and material. If a conductor has less metal than stated, its resistance will be higher than the limit. This is the most reliable way to catch undersized conductors.
| Size | Copper class 2, max Ω/km at 20 °C | Aluminium class 2, max Ω/km at 20 °C |
|---|---|---|
| 16 mm² | 1.15 | 1.91 |
| 35 mm² | 0.524 | 0.868 |
| 95 mm² | 0.193 | 0.320 |
| 240 mm² | 0.0754 | 0.125 |
How to use this:
- Ask for the factory routine test report showing measured resistance for each drum.
- On arrival, cut a sample from selected drums and have an independent laboratory measure resistance, corrected to 20 °C.
- Also check insulation thickness, sheath thickness and the actual drum length against the order.
What to check with a Chinese supplier
- Type-test report. Ask for a full type-test report to IEC 60502 for the same construction and voltage, issued by an independent laboratory. A report for a different size range or voltage is not enough.
- Routine and sample tests. Conductor resistance, voltage test, and for MV cables partial discharge, on every drum.
- Certification. CCC applies to certain cables sold in China; for export, ask for the certificates your market requires, such as CB scheme reports or local approvals. ISO 9001 shows a quality system, not product compliance.
- Factory or trader. Cable is easy to rebrand. Confirm the production address and ask whether the sheath will carry the factory's name.
- Registered entity. Check the company against its Unified Social Credit Code.
- Pre-shipment inspection. Book a third-party inspector to measure resistance and dimensions before the container is loaded.
Our rankings measure how complete a company's public data is, not product quality. See the methodology page for how scores are built.
Common mistakes
- Accepting "equivalent to IEC" without a test report.
- Not specifying the MV screen cross-section, which must carry earth-fault current.
- Using steel armour on single-core AC cables.
- Paying the balance before resistance results are available.
- Forgetting cable accessories such as terminations and joints rated for the same cable.
Frequently asked questions
Which standard should I specify for LV and MV power cables?
IEC 60502-1 for cables rated 1 kV and 3 kV, and IEC 60502-2 for 6 kV to 30 kV. Conductors should comply with IEC 60228.
Is XLPE always better than PVC?
XLPE carries more current and suits MV cables, but PVC is still widely accepted for LV wiring. Choose based on your installation code, fire requirements and current rating.
How do I know the conductor is not undersized?
Measure DC resistance and compare it with the IEC 60228 maximum for that size and material. A result above the limit means the conductor does not meet its stated size.
Do I need armoured cable for underground installation?
Direct-buried cables usually need armour, while cables in ducts may not. Check your local wiring regulations and the mechanical risks on site.