WDZBN-YJY Class B Low Smoke Zero Halogen Fire Retardant XLPE Insulated LSZH Sheathed Power Cable for Mid-Rise Commercial, School & General Public Construction

WDZ:

Low-Smoke Zero-Halogen (LSZH); utilizes halogen-free insulation and sheathing materials that do not release toxic or corrosive halogen gases during combustion.

B:

Class B flame-retardant rating; suitable for most mid-to-high-rise public buildings with moderate fire safety design requirements.

N:

Enhanced flame-retardant type; employs an optimized polyolefin formulation to improve flame-retardant performance (inhibiting flame spread) during bundled installation.

YJ:

Cross-linked polyethylene (XLPE) insulation layer; characterized by high-temperature resistance, low dielectric loss, and stable long-term electrical performance.

Y:

Low-smoke zero-halogen polyolefin outer sheath (LSZH sheath); PVC-free, featuring low smoke density and low toxicity.

The WDZBN-YJY is a Class B low-smoke zero-halogen flame-retardant power cable offering a balanced cost-performance ratio; it is positioned between the high-end WDZA-YJY (Class A ultra-low-smoke flame-retardant type) and the standard WDZB-YJY. This model utilizes a Class N flame-retardant formulation that enhances resistance to vertical flame spread in bundled installations, meeting mandatory LSZH wiring requirements for most mid-to-high-rise commercial buildings, schools, community facilities, and underground auxiliary spaces. By effectively controlling overall material costs while ensuring core fire safety standards, it serves as the preferred solution for public infrastructure projects requiring moderate fire safety ratings.

• Class 2 oxygen-free compacted stranded copper conductors: Feature a circular stranded design that ensures low DC resistance and high strand roundness, effectively enhancing overall current-carrying capacity
• Irradiation-crosslinked XLPE insulated cores: Produced via a continuous crosslinking process, offering a long-term thermal rating of 90°C and excellent resistance to aging and water-treeing
• Eco-friendly Low-Smoke Zero-Halogen (LSZH) filler layer: Utilizes a flexible halogen-free polyolefin material to fill the interstices between cores, ensuring a circular cable profile and minimizing heat accumulation during dense, multi-layer installations
• Integrated wrapping/separation layer: Tightly encases the cable core assembly, protecting the insulation from friction-induced damage during pulling and conduit installation
• WDZBN Class B enhanced flame-retardant LSZH outer sheath: Formulated using an optimized flame-retardant masterbatch blending process, effectively inhibiting vertical flame propagation under bunched-cable combustion conditions

• GB/T 12706.1, GB/T 19666, GB 31247 (testing specifications for low-smoke, halogen-free cables), GB 50016 (Code for Fire Protection Design of Buildings), GB 50217 (Code for Design of Electrical Installations of Civil Buildings)

• IEC 60228 (conductor standards), IEC 60332-3 (bunched-cable flame retardancy test), IEC 61034 (smoke density test), IEC 60754 (halogen emission test)

Standard voltage ratings: 0.6/1kV (covering over 98% of indoor fixed power distribution projects in public buildings)

Customized special medium/low voltage: 1.8/3kV, specifically for auxiliary power supply circuits in underground utility tunnels

Single-core WDZBN-YJY: 1.5mm² – 630mm²

Multi-core WDZBN-YJY: 2/3/4/5 cores; composite core configurations (3+1 / 3+2 / 4+1); cross-section range: 1.5mm² – 400mm²

Conductor material standard: 99.99% T2-grade virgin oxygen-free copper, utilizing a compacted stranding process designed to minimize inter-strand gaps and optimize current-carrying capacity.

• Long-term continuous operating temperature: 90°C (20°C higher than PVC-insulated VV-type cables), supporting stable operation under higher loads
• Instantaneous short-circuit thermal limit: Withstands 250°C for 5 seconds without insulation melting or dielectric breakdown
• Class B enhanced bunched flame-retardant performance: Passes the IEC 60332-3B vertical bunched cable combustion test; flame spread is strictly controlled during multi-cable installation in vertical shafts
• Low-smoke performance (Class B standard): Smoke light transmittance ≥60% during combustion, ensuring basic visibility for personnel evacuation
• Halogen-free characteristics: Total halogen emission <0.5%; produces no corrosive hydrogen chloride gas, preventing damage to the human respiratory tract and firefighting equipment
• Minimum installation bending radius: 12 times the outer diameter for multi-core cables; 15 times the outer diameter for large-cross-section single-core cables
• Installation ambient temperature range: -20°C to +70°C; allows for normal installation without preheating in low-temperature winter conditions
• Routine factory withstand voltage test: All finished cables pass a 3.5kV AC withstand voltage test (duration: 5 minutes), ensuring no insulation breakdown prior to batch delivery

• Small cross-section (1.5 mm² – 10 mm²): Branch circuits for emergency lighting and evacuation signage in public areas; fire alarm control circuits.
• Medium cross-section (16 mm² – 185 mm²): Power distribution feeders for office floors; main power lines for public areas in school academic buildings; equipment power supply lines for community commercial centers.
• Large cross-section (240 mm² – 630 mm²): Main incoming power cables for building distribution rooms; main power feeders for underground parking garages.

• 3.1 Enhanced Class B Flame-Retardant Formula for Safer Bundled Installation
  Compared to standard WDZB-YJY cables, the WDZBN-YJY incorporates a high-efficiency, halogen-free flame-retardant masterbatch into its outer sheath formulation. When dozens of cables are installed in dense bundles within enclosed cable shafts or trays, this product effectively inhibits vertical flame propagation, preventing fire from spreading floor-by-floor along the electrical shafts of high- and mid-rise buildings. This enhanced flame-retardant performance (Class N) is a common mandatory tender requirement for school and community commercial complex projects.
• 3.2 Balancing LSZH (Low-Smoke Zero-Halogen) Fire Performance with Overall Project Costs
  While meeting mandatory national fire safety standards for low-smoke zero-halogen cables, the raw material cost of this cable is significantly lower than that of Class A WDZA-YJY cables. For projects such as mid-to-high-rise office buildings, primary and secondary schools, and community commercial centers—where there are no requirements for extreme smoke density suppression—selecting WDZBN-YJY cables ensures successful fire safety inspection while reducing cable procurement costs by 20%–30%, thereby helping purchasers optimize the overall electrical material budget.
• 3.3 XLPE Insulation Enhances Current-Carrying Capacity and Extends Service Life
  XLPE insulation allows for a continuous operating temperature of up to 90°C; for a given conductor cross-section, the effective current-carrying capacity is 18% higher than that of traditional PVC-insulated cables. Suitable for installation in densely packed multi-layer cable trays within office buildings and schools, these cables effectively mitigate the risk of heat accumulation associated with long-term full-load operation. With a design service life of 70 years—aligning with the full lifecycle of public buildings—they reduce the investment costs associated with mid-term cable replacement or system retrofitting.
• 3.4 Wide operating temperature range and environmental adaptability reduce auxiliary installation costs
  The cable utilizes a low-smoke zero-halogen (LSZH) polyolefin sheath that offers excellent low-temperature performance; it allows for normal installation at -20°C without preheating, meeting the demands of municipal construction projects during northern winters. Additionally, the sheath provides resistance to UV radiation and mild acid/alkali corrosion, making it suitable for indoor cable shafts, semi-open cable trenches, underground garages, and utility tunnel auxiliary circuits without the need for heavy-duty anti-corrosion protective conduits.
• 3.5 Low-toxicity, halogen-free characteristics eliminate secondary fire hazards
  The cable contains no halogenated PVC components. In the event of a fire, it produces only a small amount of non-toxic white smoke and releases no corrosive acidic gases. This prevents casualties caused by the inhalation of toxic fumes during evacuation and protects fire alarm systems, smoke exhaust systems, and other fire-linked equipment from permanent corrosion damage, fully complying with fire safety design requirements for high-occupancy educational and commercial buildings.
• 3.6 Stable, large-scale production processes ensure consistent fire-performance metrics across batches.
  The process utilizes automated integrated extrusion lines, a fixed low-smoke zero-halogen (LSZH) flame-retardant formulation, and a standardized cross-linked polyethylene (XLPE) cross-linking process. Variations in key indicators—such as smoke density, halogen content, and flame-retardant performance—across production batches are kept to a minimum, thereby eliminating the risk of project fire-safety inspection failure caused by inconsistent cable quality between batches.

• Mid-to-high-rise commercial and office buildings (height: 24m–100m)
  Floor power distribution risers, emergency lighting circuits for public areas, control lines for smoke exhaust fans, and main power supply for underground equipment rooms
• Educational public building projects
  Public power supply and evacuation lighting circuits for primary and secondary schools, university teaching buildings, student dormitories, and cafeterias
• Community-supporting commercial facilities and public areas in residential zones
  Fire control lines for residential underground garages, community supermarkets, property management offices, and public activity spaces
• Municipal auxiliary underground spaces
  Auxiliary power supply for urban underground utility tunnels; power distribution cables for ventilation and lighting in underground pedestrian passages
• Government public service buildings
  Fire safety circuits for district-level cultural centers, community health service stations, and public sports arenas (excluding super-high-rise buildings)

Case 1: Electrical Infrastructure Project for the New Campus of a Key Secondary School
The project's electrical design team specified WDZBN-YJY 0.6/1kV multi-core cables for the main power distribution lines serving the academic buildings, dormitories, and the cafeteria. Given the high student density and the requirement for a "medium" fire safety rating, the WDZA-YJY variant was rejected due to excessive cost, while standard WDZB-YJY cables failed to meet fire department standards for bunched-cable flame retardancy. Our company provided comprehensive test reports for Class B enhanced flame retardancy and LSZH (Low Smoke Zero Halogen) certification, ensuring the project passed the fire safety inspection on the first attempt without requiring any remedial work. Featuring a high-ampacity XLPE (cross-linked polyethylene) structure, the cable effectively mitigated heat accumulation issues associated with multi-layer cable tray installations in the buildings' electrical rooms; after a year of full-load operation, no overheating-related faults occurred.

Case Study 2: Electrical Retrofit for a 16-Story Community Shopping Complex
The general contractor’s procurement team selected the WDZBN-YJY cable series for shop power supply, corridor emergency lighting, and basement fire pump control circuits. The cable's enhanced flame-retardant (N-type) sheath effectively mitigates the risk of flame spread within enclosed basement cable shafts, while the low-smoke, zero-halogen (LSZH) material—capable of withstanding a wide temperature range—is perfectly suited to the perpetually humid basement environment. We provided customized cut-to-length services based on the mall's zoning layout; compared to bulk purchasing in uniform lengths, this reduced cable material waste by 11%, effectively controlling the project's overall electrical procurement costs.

Case Study 3: New Construction of a District Government Cultural Center
Municipal tender documents explicitly required Class B enhanced LSZH flame-retardant cables, and the design team designated WDZBN-YJY as the sole specified model. Our technical engineers assisted the purchaser in compiling all necessary CCC certifications, IEC combustion test reports, and tender specification compliance tables. This documentation fully met the government tender's rigorous comparative criteria, significantly boosting the contractor's evaluation score. Upon project completion, fire and rescue authorities conducted on-site random combustion tests; all smoke density and flame-retardancy metrics met national standard limits, and the project successfully passed final acceptance.

• Voltage Rating Selection Principles: Standard 0.6/1kV WDZBN-YJY cables are used for fixed installations in indoor mid-to-high-rise public buildings; customized 1.8/3kV specifications may be selected for auxiliary power distribution in long-distance utility tunnels.
• Conductor Cross-Section Calculation Logic: Required conductor cross-sections are calculated based on total equipment load power, incorporating a 15% load margin to accommodate future equipment expansion; leveraging the high current-carrying capacity of XLPE (cross-linked polyethylene) eliminates the need to oversize conductors—as is required for aluminum-core VLV cables—thereby balancing safety and material costs.
• Core Count Matching Standards: 3-core WDZBN-YJY cables are selected for single-phase emergency lighting branch circuits; 4-core cables are used for three-phase fire-fighting equipment main lines; composite 3+1 or 4+1 core cables are selected for medical and public utility equipment requiring independent grounding protection.
• Application Matching and Exclusion Notes: WDZBN-YJY is the optimal choice for public buildings with moderate fire safety ratings; core emergency evacuation circuits in super-high-rise buildings, subways, and large hospitals must be upgraded to Class A WDZA-YJY cables; installations in workshops with long-term exposure to highly corrosive chemicals require isolation protection using fully enclosed steel conduits.

• Vertical installation in multi-level cable shafts: Fixed supports must be installed at 1.5-meter intervals to prevent damage to the LSZH (Low Smoke Zero Halogen) outer sheath caused by the cable's own weight; for bundled installations, a 25% heat dissipation gap must be maintained between cables to prevent temperature rises from reducing actual current-carrying capacity.
• Bending control: Minimum bending radius standards must be strictly observed; excessive bending can cause permanent cracks in the flame-retardant outer sheath, thereby compromising fire safety performance.
• Installation in underground garages and utility tunnels: For direct burial, sand bedding layers (both top and bottom) and a brick protective layer are required to prevent sharp stones from puncturing the cable sheath; when using cable trays, fire-resistant partitions should be employed for layered routing.
• Low-temperature installation specifications: Installation can proceed normally without preheating at temperatures as low as -20°C, making it suitable for electrical installation projects on campuses and municipal sites in northern regions during winter.

• Pre-order Qualification Verification: Verify that the supplier can provide CCC mandatory certification, a third-party test report for Class B enhanced flame retardancy, and a test certificate confirming Low-Smoke Zero-Halogen (LSZH) characteristics.
• On-Delivery Spot Checks: Inspect the outer sheath for complete laser markings (including the model "WDZBN-YJY 0.6/1kV" and cross-sectional specifications); check the compactness of the copper core and the uniformity of the XLPE insulation layer thickness. For government, school, and municipal tender projects, samples must be taken and submitted to a third-party testing agency for spot checks on smoke density and flame retardancy performance.
• Delivery Schedule Planning: For bulk orders—such as those for large campuses or community commercial centers—it is recommended to place orders 10–15 working days in advance. This allows sufficient time for raw material processing, finished product spot checks, and packaging/shipping, thereby avoiding construction delays caused by cable supply shortages.

• Full Compliance with National Standards: All WDZBN-YJY cables fully comply with the mandatory testing standards for Low-Smoke Zero-Halogen (LSZH) cables (GB 31247) and the requirements of the Code for Fire Protection Design of Buildings (GB 50016); all performance indicators meet the review criteria of construction quality supervision stations and fire rescue agencies.
• International Testing Qualifications: The products meet international fire safety testing standards such as IEC 60332, IEC 61034, and IEC 60754; test reports are suitable for tender registration for overseas public building projects.
• A complete documentation package accompanies every shipment: CCC certification, Class B flame-retardant test reports, Low-Smoke Zero-Halogen (LSZH) inspection sheets, factory batch inspection reports, quality certificates for T2 copper and LSZH plastic raw materials, technical specification compliance tables for tenders, and special VAT invoices.
• Batch quality consistency control: All product batches utilize a standardized flame-retardant LSZH masterbatch formula and a uniform XLPE cross-linking production process. Batch-to-batch fluctuations in key fire-safety metrics are minimal, effectively eliminating the risk of acceptance failure caused by substandard cable batches.

The product range is extensive, covering everything from small-gauge evacuation branch lines (1.5mm²) to large-cross-section backbone cables (630mm²). Ample stock of standard models is maintained for schools, offices, and commercial community projects to ensure rapid delivery. Customization services—such as cutting to specific lengths, laser-printing project-specific identifiers on the sheath, and upgrading fire resistance with double-layer mica tape for critical fire-safety circuits—are available. This enables one-stop, centralized procurement of premium LSZH flame-retardant cables, eliminating the need to coordinate with multiple suppliers.

We exclusively utilize high-quality imported low-smoke, zero-halogen (LSZH) flame-retardant masterbatches and prime-grade T2 oxygen-free copper, strictly prohibiting the use of inferior recycled halogen-free plastics that fail to meet smoke emission and flame-retardancy standards. We implement a four-tier inspection process: testing incoming raw materials for halogen content and flame-retardant properties; real-time online monitoring of copper conductor stranding; automated measurement of XLPE insulation thickness; and batch-based vertical-tray flame spread testing of finished cables. This approach effectively eliminates common defects found in products from smaller manufacturers, such as inadequate flame retardancy, excessive smoke emission, and insufficient insulation thickness.

By eliminating intermediaries, we offer tiered volume discounts for bulk orders intended for schools and municipal projects. Our senior in-house electrical engineers provide complimentary services—including load current calculations, optimization of cable cross-section selection, and thermal dissipation designs for vertical shaft layouts—to assist clients in selecting the most cost-effective WDZBN-YJY cable specifications that fully comply with fire-safety standards, thereby reducing the total investment in electrical materials for the project.

Our team of electrical engineers, boasting over 12 years of experience in public building design, provides comprehensive technical support to design institutes and general contractors. Services include consulting on evacuation circuit design for public buildings, providing downloadable current-carrying capacity reference tables for WDZBN-YJY cables, compiling documentation to address fire safety specifications in tenders, and offering guidance on preparing materials for fire safety inspections. For government tenders involving projects such as schools and cultural centers, we assist in creating fire safety specification comparison charts that meet stringent tender requirements, thereby enhancing the contractors' competitiveness in winning bids.

Multiple automated continuous XLPE cross-linking extrusion lines ensure a high daily output of WDZBN-YJY cables, supported by extensive on-site stockpiles of LSZH (Low-Smoke Zero-Halogen) plastic compounds and copper raw materials. Even when handling massive bulk orders—such as those for new campus construction or large-scale community commercial renovations—we guarantee strict adherence to delivery schedules, eliminating the risk of project work stoppages caused by supply chain shortages.

All delivered WDZBN-YJY cables come with a 15-year manufacturer's quality warranty covering key fire safety performance indicators. Should technical challenges arise during installation, a professional technical team is available to provide remote video guidance within 24 hours; furthermore, complimentary on-site installation training can be arranged for long-term partners, such as school developers and municipal contractors. Dedicated profiles are established for stable bulk-procurement clients, and raw materials are stockpiled in advance based on project schedules to shorten delivery times for subsequent orders.

The WDZBN-YJY (Class B Enhanced, Low-Smoke Zero-Halogen, Flame-Retardant, XLPE-Insulated Power Cable) is a cost-optimized, standard cabling solution suitable for mid-to-high-rise office buildings, schools, community commercial complexes, and municipal underground public spaces. Combining multiple core advantages—including Class B enhanced bundled flame retardancy, low-smoke/zero-halogen/low-toxicity properties, high-temperature resistant XLPE insulation, and broad environmental adaptability—this product strikes a perfect balance between stringent fire safety design requirements and overall project material budget constraints. It effectively mitigates the risk of secondary casualties and equipment damage caused by toxic smoke and the spread of fire during building fire incidents.

As a specialized manufacturer of WDZBN-YJY cables (low-smoke, halogen-free, flame-retardant, XLPE-insulated power cables) holding both domestic CCC certification and international IEC fire-test reports, we offer a comprehensive range of standardized low-smoke, halogen-free, flame-retardant cables, along with complete documentation packages for acceptance and certification, as well as specialized technical consulting on electrical fire safety. We serve global school construction contractors, municipal engineering groups, commercial real estate design institutes, and large-scale project procurement teams, helping public building projects with moderate fire-safety requirements successfully pass fire-safety inspections and construction quality acceptance, while ensuring the long-term, safe, and cost-effective operation of public power distribution circuits throughout the building's lifecycle.