Ask a Chinese supplier for house wiring and you will get a quote full of letter codes — BV, BVR, BVV, BVVB, RV, RVV. Ask a North American electrician for the same thing and you get THHN. These are two different naming worlds, and confusing them is how buyers end up with cable that cannot pass inspection. This guide translates the Chinese codes, shows where they genuinely overlap with IEC 60227, and spells out why a BV cable is not a THHN substitute.
Why Chinese wire codes confuse overseas buyers
Chinese building wire is named by construction code rather than by a listing or a trade designation. The code tells you the conductor type, the insulation material and whether there is a sheath — but it does not, by itself, tell you the voltage rating, temperature rating, or whether the product is approved for your market. You have to ask for those separately.
Decoding the letters
- B = building wire for fixed installation.
- V = PVC — appears once for insulation, twice if there is also a PVC sheath.
- R = flexible / stranded conductor.
- L (when present, e.g. BLV) = aluminium conductor.
Put together:
| Code | Meaning |
|---|---|
| BV | Rigid (single-strand) copper conductor, PVC insulated, no sheath |
| BVR | Stranded copper conductor, PVC insulated, no sheath — flexible for fixed wiring |
| BVV | Copper conductor, PVC insulated + PVC sheathed, round |
| BVVB | Same as BVV but flat construction |
| RV | Flexible (fine-stranded) copper connecting wire, PVC insulated, no sheath |
| RVV | Flexible copper conductor, PVC insulated + PVC sheathed cord |
The good news: several of these ARE IEC 60227 designations
China's GB/T 5023 series is the national adoption of IEC 60227, which is why IEC 60227 itself uses the same-looking codes. If your supplier also states the IEC designation, the product is internationally recognisable:
| IEC 60227 designation | Code | Typical rating | Construction |
|---|---|---|---|
| 60227 IEC 01 | BV | 450/750 V | Rigid single-core, non-sheathed |
| 60227 IEC 02 | RV | 450/750 V | Flexible single-core, non-sheathed |
| 60227 IEC 05 | BV | 300/500 V | Light-duty rigid, non-sheathed |
| 60227 IEC 06 | RV | 300/500 V | Light-duty flexible, non-sheathed |
| 60227 IEC 10 | BVV | 300/500 V | Sheathed, round |
| 60227 IEC 52 | RVV | 300/300 V | Flexible cord |
| 60227 IEC 53 | RVV | 300/500 V | Flexible cord |
So BV, RV, BVV and RVV are not exotic Chinese inventions — they carry IEC 60227 designations. Always ask the supplier to write both the Chinese code and the IEC designation on the quote.
The exceptions: BVR and BVVB are largely China-specific
BVR (stranded conductor for fixed installation) and BVVB (flat sheathed) do not have a clean IEC 60227 counterpart. They exist because of Chinese installation practice — BVR pulls more easily through conduit, and BVVB is convenient for flat surface wiring. If you need these, specify them by full description (conductor class, size, voltage, construction) rather than by code alone.
Side-by-side comparison
| Code | Conductor | Insulation / sheath | Voltage | Typical use |
|---|---|---|---|---|
| BV | Rigid (Class 1) copper | PVC insulation only | 450/750 V (300/500 V light-duty) | Fixed indoor wiring in conduit |
| BVR | Stranded (Class 2) copper | PVC insulation only | 450/750 V | Fixed wiring where flexibility helps pulling |
| BVV | Rigid or stranded copper | PVC insulation + PVC sheath (round) | 300/500 V | Surface wiring, damp locations |
| BVVB | Rigid copper | PVC insulation + PVC sheath (flat) | 300/500 V | Flat surface wiring, small appliances |
| RV | Fine-stranded (Class 5) copper | PVC insulation only | 300/500 V | Internal appliance / equipment wiring |
| RVV | Fine-stranded copper | PVC insulation + PVC sheath | 300/300 V or 300/500 V | Flexible cords, extensions |
Versus North America: UL 83 (THHN / THWN / THWN-2)
UL 83 covers single-conductor thermoplastic-insulated cable — the THHN / THWN / THWN-2 family:
- 600 V rating (versus 450/750 V or 300/500 V for the IEC/Chinese family).
- THHN 90 °C dry, THWN 75 °C wet, THWN-2 90 °C wet — versus a typically 70 °C conductor rating for PVC building wire to IEC 60227 / GB/T 5023.
- Nylon jacket over PVC, sized in AWG / kcmil rather than mm².
⚠️ A BV cable is not a THHN substitute. The NEC requires listed (or AHJ-accepted) conductors; an inspector will reject a cable whose only marking is a GB/T code. Voltage rating, temperature rating, conductor sizing (mm² vs AWG) and the listing itself all differ. If your destination is the US or Canada, specify UL 83 / UL-listed, AWG size, and the exact insulation type — do not translate BV into THHN.
Versus the EU: EN 50525 plus CPR EN 50575
For the EU, cables are normally supplied to the harmonised EN 50525 series, and — because they are construction products — they also fall under the CPR: you need a reaction-to-fire Euroclass under EN 50575 (PVC building wire commonly lands at Eca or Dca) with a Declaration of Performance and CE marking. A GB/T mark does not satisfy either requirement.
Buyer checklist for an RFQ
- Give the code AND the IEC 60227 designation (e.g. "BV = 60227 IEC 01, 450/750 V").
- Specify the conductor class — Class 1 rigid, Class 2 stranded or Class 5 flexible per IEC 60228. "Copper" alone is not a specification.
- State voltage and temperature rating numerically.
- Give cross-section in mm², plus the AWG equivalent if the destination is North America.
- North America: require the UL listing. EU: require the EN 50575 DoP and Euroclass. Neither is covered by a GB/T mark.
- Ask for the construction drawing / spec sheet — codes alone leave too much room for substitution.
Conductor choice matters as much as the code: see bare copper vs tinned copper vs tinned CCA for what the conductor actually is, and the UL cable certification guide for what North American approval requires.
FAQ
Q1: Is BV the same as THHN? A: No. BV is an IEC 60227 / GB/T 5023 PVC building wire in mm² with a typically 70 °C rating; THHN is a UL 83 listed 600 V conductor with a nylon jacket and a 90 °C dry rating in AWG. They are not interchangeable in a listed installation.
Q2: What is the difference between BV and BVR? A: Both are PVC-insulated single-core building wire, but BV uses a rigid (Class 1) conductor while BVR uses a stranded (Class 2) conductor, making it easier to pull and bend in fixed installation.
Q3: Is BVV the same as RVV? A: No. BVV has a rigid or stranded conductor with PVC insulation and PVC sheath for fixed wiring (300/500 V); RVV is a flexible cord with fine-stranded conductors (60227 IEC 52/53). Different flexibility, different application.
Q4: Can I use Chinese BV wire in a US installation? A: Not on the basis of a GB/T marking. The NEC requires listed conductors and the AHJ will look for a UL mark. You must buy cable that is actually UL listed as THHN/THWN (or another accepted type) in the correct AWG size.
Q5: What voltage are BV, BVR and BVV rated for? A: Commonly 450/750 V for BV and BVR (with 300/500 V light-duty variants), and 300/500 V for BVV and BVVB. Always confirm against the supplier's spec sheet rather than assuming from the code.
Sourcing note
🔴 Disclaimer: the correspondences in this article are standard-family translations for buying guidance, not certified equivalences. Always obtain the current spec sheet and the target-market certificate before specification or acceptance.
Need building wire for a specific market — BV/BVR in mm², UL-listed THHN in AWG, or EN 50525 cable with a CPR Euroclass? Tell me the destination and I will quote the right construction — reach me on WhatsApp: Inquiry . Pricing follows the day's copper price; confirm by inquiry.
