Class B1 Low-Smoke Zero-Halogen Flame-Retardant Eco-Friendly Cable

Officially named WDZB1 Series Low-Smoke Zero-Halogen Class B1 Flame-Retardant Power Cable, it complies with national standard GB 31247-2014 Classification of Burning Performance for Cables and Optical Cables. Ranked as premium high flame-retardant cable (second only to non-combustible Class A) in China’s construction industry, it is mainly rated for 0.6/1kV low-voltage power distribution and also available for medium & high voltage grades. Its insulation and outer sheath adopt halogen-free eco-friendly polyolefin formula with multi-layer oxygen-barrier flame-retardant composite structure, integrating superior flame suppression, low smoke & non-toxicity, stable electrical performance and weather durability. It is mandatorily specified for densely populated areas with stringent fire safety standards such as metro systems and super high-rise buildingsJinHong Wi....

1. Grade Definition & Key Combustion Parameters

Combustion performance ranking (from highest to lowest): Class A (non-combustible) > Class B1 (high flame retardant / hardly combustible) > Class B2 > Class B3 (ordinary flame retardant). Class B1 cables must pass comprehensive combustion test under 20.5kW heat source with mandatory criteria:

• Maximum flame spread length ≤ 1.5m to effectively block vertical flame propagation along cables

• Peak heat release rate ≤ 30kW; total heat release within 1200s ≤ 15MJ to slow fire temperature rise

• Smoke light transmittance ≥ 60% to guarantee visibility during fire evacuation

• Top auxiliary grades: burning droplets grade d₀ (no combustible molten drips), smoke toxicity grade t₀ (negligible toxicity), corrosivity grade a₁ (low corrosion)

2. Core Performance Advantages

1. Halogen-Free & Eco-Friendly, Safe with Low Smoke & Zero ToxicityNo halogen elements (chlorine, bromine etc.) contained in insulation and sheath. No highly corrosive toxic hydrogen halide gas will be released under flame exposure. Extremely low smoke emission prevents suffocation and poisoning casualties in fires, meanwhile protects precision electrical equipment and building steel structures from corrosive damage, fully complying with EU RoHS environmental directives.

2. Superior Flame Retardancy & Fire ControllabilityEquipped with multi-layer oxygen barrier and inorganic flame retardant fillers (magnesium hydroxide, aluminum hydroxide). Water vapor released during thermal decomposition cools down flames and isolates oxygen; the cable self-extinguishes rapidly once the fire source is removed, avoiding vertical shaft & cable tray large-scale fire spread, fully meeting updated national building fire codes.

3. Stable Electrical Performance, Outstanding Heat Resistance & Current CapacityMaximum continuous operating temperature of conductor: 90℃; short-circuit instantaneous withstand temperature up to 250℃. XLPE insulation features low dielectric loss and stable insulation resistance, delivering larger current-carrying capacity and lower power loss than ordinary PVC flame-retardant cables with identical cross-section, with enhanced overload tolerance.

4. Excellent Mechanical Strength & Wide Environmental AdaptabilityGood flexibility and moderate bending radius suit various laying methods including cable tray, conduit, vertical shaft and underground utility tunnels. Steel tape/steel wire armored version is optional for compression resistance, impact resistance and rodent & termite protection. With strong UV, acid-alkali and moisture resistance, it serves reliably for over 30 years both underground and outdoor.

5. Low Corrosion & Convenient Maintenance, Reduced Post-Fire LossNo corrosive flue gas during combustion minimizes residual corrosion on circuits and equipment after fires, cutting maintenance and restoration costs drastically. Free from oil leakage and aging cracking risks, it requires minimal routine maintenance.

3. Typical Cable Structure

• Standard WDZB1-YJY: High-purity copper conductor → XLPE insulation → flame-retardant filling → oxygen-barrier isolation layer → low-smoke zero-halogen polyolefin outer sheath

• Armored WDZB1-YJY23: Extra inner lining + steel tape armor for direct burial, tunnels and harsh mechanical environments

4. Application Scenarios

Mandatorily applied in high-safety densely populated venues: metro & light rail transit, airport terminals, large hospitals, super high-rise residential & commercial complexes, exhibition centers, shopping malls, stadiums and schools. Also widely adopted for power and fire-fighting distribution circuits in data centers, financial computer rooms, radio & TV control centers, chemical parks, underground utility tunnels and civil air defense projects. It serves critical emergency power loads including emergency lighting, smoke exhaust fans, fire elevators and fire water pumps.