Reading cable designations: Cu/XLPE/SWA/PVC decoded

Three designation systems you will meet

Buyers sourcing cable from China usually see three systems on the same day. The first is the layer string used in IEC-style datasheets, such as Cu/XLPE/SWA/PVC: each abbreviation is one layer, read from the centre outwards. The second is the harmonised code used in Europe for cables up to 450/750 V, such as H07V-R or H05VV-F, defined in the EN 50525 series and its predecessors. The third is the Chinese type code, such as YJV, YJV22 or KVV, which partner plants print in their catalogues and often on the drum label. National systems add their own names: 6242Y in the UK, THHN in the US.

None of these systems is wrong. The problem is that a buyer writes one and a plant reads another, and a letter that means armour in one system means something else in the next. The desk translates every enquiry into a single, complete layer string plus the standard before asking any plant to quote.

The layer string: Cu/XLPE/SWA/PVC

Read from left to right, from conductor to sheath. Cu/XLPE/SWA/PVC means a copper conductor, XLPE insulation, steel wire armour and a PVC outer sheath. A fuller form, Cu/XLPE/PVC/SWA/PVC, shows the PVC bedding under the armour as well. Common abbreviations:

The string never stands alone. It needs the voltage, the core count and size, and the standard: "0.6/1 kV Cu/XLPE/SWA/PVC 4x35 mm2 to BS 5467" is a complete description. The same layers to BS 6724 would have LSZH bedding and sheath instead of PVC. See the armoured cables page for how these constructions differ.

Chinese type codes: YJV, YJLV, YJV22, KVV

Chinese codes are built from letters that stand for words in Chinese, followed by digits for armour and sheath. The ones that appear most in partner plant catalogues:

• YJ = XLPE insulation; V = PVC; so YJV is a copper XLPE/PVC power cable, the reference 0.6/1 kV 4x25 mm2 model on our LV power cable page.
• L = aluminium conductor; YJLV is the aluminium version, like the 4x95 mm2 reference on the aluminium cables page. Copper is assumed when no letter is given.
• 22 = steel tape armour with a PVC outer sheath; YJV22 is the Cu/XLPE/STA/PVC construction. Other two-digit suffixes indicate other armour and sheath combinations and should be confirmed on the datasheet.
• K = control cable; KVV is a PVC insulated, PVC sheathed control cable to GB/T 9330. P = screen, so KVVP adds a braided screen.

These codes are compact but national. A buyer in Europe or Africa should never put "YJV22" alone on a purchase order; translate it into the layer string and the IEC or national standard the project calls for.

Harmonised codes: H07V-R and H05VV-F 3G1.5

European harmonised codes describe low-voltage wires and cords position by position. The first part gives the approval basis and voltage: H for a harmonised type, 05 for 300/500 V and 07 for 450/750 V. Next come the insulation and sheath letters, where V is PVC and R is rubber. The suffix after the dash gives the conductor: -U solid (Class 1), -R stranded (Class 2), -K flexible for fixed installation (Class 5) and -F flexible for cords.

So H07V-R is a 450/750 V single-core PVC wire with a stranded conductor, the type sold as the 60227 IEC 01 reference on our building wire page. H05VV-F 3G1.5 is a 300/500 V PVC insulated, PVC sheathed flexible cord with three cores of 1.5 mm2, where G means one core is green-yellow; X in the same position means no green-yellow core. The solar code H1Z2Z2-K follows similar logic for EN 50618: halogen-free cross-linked insulation and sheath over a Class 5 tinned copper conductor.

UK and US names

Some markets use product names that are neither layer strings nor harmonised codes. In the UK, 6242Y is the flat twin and earth cable to BS 6004, with PVC insulation and a PVC sheath; the Y stands for the PVC sheath. Its LSZH counterpart to BS 7211 is 6242B, where B indicates the low smoke zero halogen sheath. Armoured cables are usually named by standard, BS 5467 for PVC bedding and sheath, BS 6724 for LSZH, with the layer string alongside.

In the US, building wire is named by insulation type letters defined in NEC Article 310 and the UL standards. THHN and THWN-2 are thermoplastic insulated conductors with a nylon jacket made to UL 83; XHHW-2 is a cross-linked insulated conductor without nylon, made to UL 44. The letters encode insulation material, temperature and wet or dry use, and the -2 suffix marks a 90 C rating in both dry and wet locations. Sizes are in AWG or kcmil rather than mm2, so a US order needs the size system stated as clearly as the type. Whether a given construction is acceptable on site depends on its listing and the authority having jurisdiction, so the listing is checked per order rather than assumed from the type name.

Turning a designation into a purchase order

Whatever system your customer or engineer uses, the purchase order should carry the same five elements, written out in full:

1. Voltage rating: 0.6/1 kV, 450/750 V, 8.7/15 kV and so on, explained in our post on cable voltage ratings.
2. Layer string: conductor, insulation, any screen, bedding, armour and sheath.
3. Cores and size: for example 4x35 mm2 or 3x95 mm2, with conductor class if it matters.
4. Standard: IEC 60502-1, BS 5467, BS 6724, IEC 60227, EN 50618, UL 83 or the national standard required.
5. Marking and packing: sheath legend, metre marks and drum length.

Where the designation is ambiguous, the desk asks before quoting rather than guessing, and records the answer in the spec sheet that every plant quotes against. Send the codes you have through the quote form and the desk returns a written construction for you to confirm.