LSZH Fire-survival Copper Wiring for Mid-to-high Grade Closed-space Public & Industrial Engineering

WDZ = Low-smoke halogen-free; B = Class B flame-retardant; N = Fire-resistant; YJY = XLPE insulation + LSZH polyolefin outer sheath. All insulation, sheath, and fillers are made from halogen-free, environmentally friendly polymer raw materials free of halogens and harmful heavy metal additives.

High-purity compacted copper conductor + inorganic fire-resistant coating + XLPE insulation + halogen-free low-smoke filler + integrally extruded LSZH outer sheath, without a metal armor layer.

The preferred cable for projects requiring both fire-resistant continuous power supply and low-smoke, non-toxic combustion performance. It is widely applicable to mid-to-high-end medical buildings, medium-sized rail transit auxiliary spaces, enclosed underground equipment rooms, fire protection circuits in high-end commercial complexes, mainstream procurement models for domestic government landmark projects, and bidding for mid-to-high standard infrastructure in the Middle East and Southeast Asia.

Complete set of standard technical specifications and complete specifications

• Raw materials: ≥99.97% electrolytic copper, conforming to IEC60228 standard; two optional types: Category 1 solid copper/Category 2 tightly stranded copper
• Core wire configuration: 1C/2C/3C/4C/5C/3+1/3+2 full series of composite multi-core
• Cross-sectional area range: Standard stock: 1.5mm²~300mm²; Extra-large custom specifications: 400~630mm², suitable for high-current main incoming line projects
• Quality control: The DC resistance of the finished conductor is strictly limited to below the national standard upper limit to control long-term line losses

• XLPE (Cross-Linked Polyethylene) Insulation: Long-term allowable operating temperature 90℃, instantaneous short-circuit withstand temperature up to 250℃, low dielectric loss, and excellent heat resistance under densely bundled installation.
• Inorganic Fire-Resistant Coating: Core structural layer, achieving Class N fire resistance, tightly wrapped between the conductor and XLPE insulation.
• Inner Filler: Halogen-free, low-smoke, environmentally friendly filler that does not release toxic fumes under open flame and maintains cable roundness.
• Outer Sheath: Modified low-smoke, halogen-free polyolefin material, suitable for ambient temperatures -30℃ to +70℃, anti-aging, moisture-proof, and has a certain resistance to mild chemical corrosion.

• Rated Operating Voltage: 0.6/1kV
• Factory Routine Withstand Voltage Test: 3.5kV/5min No insulation breakdown
• Comprehensive Fire Resistance Performance: Meets GB/T19666 Class B vertical flame retardant + fire resistance performance, maintaining continuous power supply for a specified time under standard flame conditions; smoke density and gas toxicity pass LSZH authoritative third-party testing.

• 3.1 Dual Core Fire Resistance Performance Integration

  Integrates Class B flame retardant + Class N fire resistance, suppressing flame spread along the cable body while maintaining uninterrupted power supply for the specified burning time, achieving a dual effect of fire protection + emergency power supply guarantee, and can replace the separately equipped fire-resistant cable + ordinary flame-retardant cable in many projects.

• 3.2 Low Smoke Halogen-Free and Non-Toxic Combustion

  The entire cable contains no halogen components; the amount of smoke during combustion is small, with no dense black smoke or corrosive toxic gases, protecting the escape line of sight and precision electrical equipment in confined spaces from gas corrosion.

• 3.3 Superior High-Temperature Aging Resistance

  Utilizing cross-linked polyethylene (XLPE) insulation and a modified low-smoke halogen-free (LSZH) sheath formula, its heat resistance is far superior to that of polyvinyl chloride (PVC) insulated cables, making it suitable for high-heat-accumulation environments such as dense cable shafts and enclosed equipment rooms.

• 3.4 Green and Environmentally Friendly All-Component Design

  All raw materials are free of heavy metals and halogen additives, meeting domestic green building evaluation standards and international LEED green engineering material access requirements.

• 3.5 Lightweight Unarmored Structure Advantages

  The streamlined unarmored structure offers moderate flexibility, facilitating pre-embedded conduit wiring and high-rise vertical shaft traction installation, effectively shortening construction time and reducing labor costs.

• 3.6 Excellent Moisture and Mildew Resistance

  The integrally extruded low-smoke halogen-free (LSZH) outer sheath, combined with a compact inner wrapping structure, effectively blocks the penetration of moisture and condensation, making it suitable for damp basements and semi-buried cable trench installation environments.

• 3.7 Extended Service Life

  Antioxidant and UV-resistant additives are added to the raw materials of the sheath. Under standardized installation and rated load operation conditions, the design service life exceeds 35 years, reducing the owner's investment in subsequent circuit upgrades.

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• 4.1 Class B and General Standard Hospital Construction

  Application Scenarios: Power supply for fire pumps in inpatient buildings, emergency lighting circuits in wards, auxiliary fire protection power distribution lines in medical equipment rooms; the medical industry has strict requirements for both low toxicity and fire resistance.

• 4.2 Urban Rail Transit and Underground Public Facilities Spaces

  Application Scenarios: Power supply circuits for auxiliary equipment in substations, fire linkage circuits in underground pedestrian passages, dedicated emergency fire protection circuits for non-main trunk tunnels; enclosed underground spaces need to simultaneously provide smoke extraction and continuous power supply for fire protection.

• 4.3 Mid-to-High-End Commercial Complexes and Super High-Rise Office Buildings

  Application Scenarios: Power supply for smoke extraction fans in shopping malls, backup circuits for fire elevators in high-rise buildings, emergency power distribution trunk lines in underground parking lots.

• 4.4 Indoor Enclosed Energy Storage and Centralized Photovoltaic Power Stations

  Scenario: Fire-resistant auxiliary power circuits for energy storage containers, emergency disconnection control lines for equipment rooms; enclosed power station equipment rooms have strict fire safety and environmental protection access regulations.

• 4.5 Municipal Public Landmarks and Key Government Projects

  Application Scenarios: Emergency power distribution for fires in municipal cultural museums and comprehensive sports stadiums; dedicated fire control circuits for core fire protection systems in government office buildings; WDZBN-YJY type cables are preferred for government bidding projects to ensure compliance with regulations.

• Model Grade Selection Recommendations:

  WDZBN-YJY type cables are suitable for enclosed rooms, underground tunnels, and core fire protection circuits in medical facilities; WDZB-YJY type cables can be selected for non-emergency circuits in open-air general factory buildings to optimize project costs; our technical team can provide free consultation services on matching local fire protection regulations based on the project location.

• Construction Bending Control:

  Minimum bending radius ≥ 12 times the outer diameter of the finished cable to avoid sharp pipe edges scratching the low-smoke halogen-free sheath during pipe thread installation.

• Dense Shaft Layout Requirements:

  Multi-layer bundled cables require reserved space for fixed heat dissipation; the manufacturer provides current carrying capacity data tables for different laying methods for load calculation and cable gauge selection.

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• Scientific Zoning Procurement:

  The project is divided into emergency fire protection circuits and general power distribution circuits; only critical fire protection circuits are equipped with WDZBN-YJY, while general non-fire protection areas use conventional YJY/WDZB-YJY, avoiding over-procurement and waste.

• Phase-Based Flexible Delivery:

  Supports phased delivery according to the project construction progress, reducing the buyer's on-site warehouse occupancy and capital costs.

• Customized for Special Environments:

  For coastal areas with high salt spray or workshops with trace amounts of volatile chemicals, salt corrosion-resistant, enhanced low-smoke halogen-free sheaths can be customized before order confirmation.

• Domestic Certifications: CCC mandatory certification, national third-party LSZH test report, flame retardant + fire resistance dual-performance type test certificate.
• International Compliance: Complies with IEC60332 and IEC61034 international LSZH testing standards, and meets the access requirements of local engineering bidding regulations in Southeast Asia and the Middle East.
• Bidding Assistance: The complete set of certification documents can be compiled into formal bidding materials to help the procuring party successfully complete the qualification review for government bidding and overseas EPC projects.

• Case 1: New Fire Protection Wiring Project for a General Hospital in the Middle East (2025)

  The local EPC contractor purchased 63km of mixed-grade WDZBN-YJY (3×4~5×35mm²) cable for emergency power supply and fire pump wiring in the inpatient building. Local medical building regulations required the cable to have low smoke, non-toxicity, and fire resistance dual indicators. All cables passed third-party fire and smoke resistance tests. The buyer signed an annual framework procurement contract after project acceptance.

• Case Study 2: Power Supply Renovation Project for Auxiliary Integrated Utility Tunnels in New Urban Areas in China (2024)

  The municipal engineering procurement department centrally procured 49km of WDZBN-YJY type multi-core cables for fire protection power distribution in underground corridors. The enclosed tunnel space placed dual demands on smoke prevention and continuous power supply for fire protection; all products passed the construction quality supervision spot check.

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• Pre-sales Technical Services for Design Engineers

  Free assistance services including specification selection, current carrying capacity verification, and bidding technical parameter sorting; providing editable electronic data sheets and scanned complete certification documents.

  Custom production of non-standard cross-sections and modified low-smoke halogen-free sheaths for special environments.

• Bulk Order Cost and Delivery Advantages

  Direct factory supply, no middlemen markups; tiered pricing for large-volume and long-term framework contracts; stable inventory of copper and low-smoke halogen-free raw materials effectively reduces the impact of raw material price fluctuations.

  Mainstream standard specifications are readily available to meet urgent short-cycle order needs; customized products are equipped with dedicated production lines to shorten production cycles.

• After-sales and Bidding Support

  Products adhere to national standard quality assurance; on-site professional construction technical guidance is provided for large-scale landmark projects.

  Official factory authorization letters and complete qualification documents are provided to assist buyers in improving their success rate in domestic and international engineering bids.