In the wire and cable industry, every letter and number in a model carries specific meaning. Being able to decode a full specification at a glance saves time in procurement, installation, and quality inspection. This guide walks through several real-world examples to illustrate how model codes work in practice.

1. Basic Single-Core Wire: BV4

→ Single copper core PVC insulated wire, 4 square millimeters.

This is one of the most common building wires for fixed residential and commercial wiring. The absence of "L" confirms a copper conductor; the absence of "R" confirms a solid (non-flexible) conductor.

2. Coaxial Cables: SYV and SYWV

SYV 75-5-1 (A / B / C)

→ Solid PE insulated RF coaxial cable, 75Ω, 5mm OD, single-core, with specified braid count.

Higher braid counts (B or C) provide better shielding effectiveness, reducing signal interference in demanding environments.

SYWV 75-5-1

→ Foamed PE insulated RF coaxial cable, 75Ω, 5mm OD, single-core.

The key difference from SYV is the foamed dielectric (W), which reduces attenuation and improves high-frequency performance — making SYWV the preferred choice for modern CATV and satellite systems.

3. Flexible Shielded Cable: RVVP 2×32/0.2

→ Copper core PVC insulated and sheathed shielded flexible cable, 2 cores, each core consisting of 32 strands of 0.2 mm copper wire.

For comparison, here are two related models decoded the same way:

4. Flame-Retardant Twisted Pair: ZR-RVS 2×24/0.12

→ Flame-retardant flexible PVC insulated twisted-pair connecting wire, 2 cores, each with 24 strands of 0.12 mm copper.

Commonly used in fire alarm systems, broadcast audio, and control circuits where flame retardancy and flexibility are both required.

5. Sheathed Cable with Multiple Cores: ZR-BVV 3×6.0

→ Flame-retardant copper core PVC insulated and PVC sheathed round cable, 3 cores × 6.0 mm².

Often used for three-phase power distribution or single-phase + earth configurations in exposed installations.

6. Fire-Resistant Power Cable: NH-VV 3×70 + 2×35

→ Fire-resistant copper core PVC insulated and PVC sheathed power cable: 3 × 70 mm² + 2 × 35 mm².

This is a 5-core power cable​ configuration — the three larger conductors carry the three phases, while the two smaller ones serve as neutral and protective earth (PEN). The fire-resistant (NH) property ensures the circuit remains operational for a specified time during a fire, making it suitable for emergency power feeds.

Quick Reference: How to Decode Any Model

When faced with an unfamiliar cable designation, break it down into layers:

[Property Prefix] – [Series/Insulation] – [Sheath/Shield/Armor] – [Core Count × Conductor Size]

Key Takeaways

1. Numbers after letters tell the physical story​ — core count, strand count, wire diameter, cross-sectional area, impedance, and outer diameter all appear in a predictable order.

2. Slash notation (32/0.2)​ means "32 strands of 0.2 mm diameter" — multiply to estimate total cross-section: 32 × π × (0.1)² ≈ 1.0 mm².

3. Plus-sign notation (+ 2×35)​ indicates auxiliary cores — typically neutral and earth in power cables.

4. Letter order follows construction order​ — conductor → insulation → shielding → sheath → armor, from inside out.

Pro Tip:​ When verifying a cable delivery, always check that the printed model on the jacket matches the purchase specification — including every prefix and suffix. A missing "NH" or "ZR" changes the cable's safety classification entirely.