Fire Resistant PVC Insulated PVC Sheathed Copper Power Cable For Fire Lifeline,

• NH: Fire-resistant (fireproof) characteristics. It can maintain continuous power supply for a specified time under 950℃ flame combustion and water spray impact. This is the core functional difference between NH-VV and ordinary ZR flame-retardant cables.
• V: PVC polyvinyl chloride insulation core layer, using a special fire-resistant mica winding composite structure.
• V: Integral extruded PVC outer sheath.

Rated voltage level: U0/U = 0.6/1kV low-voltage three-phase AC civil emergency power distribution system.

Conductor configuration can be customized: single core/double core/three core/four core/five core, Class 2 T2 oxygen-free copper solid core, cross-sectional area range 1.5mm²～300mm², suitable for small emergency lighting branches to large fire pump main lines.

They use Class 2 T2 oxygen-free copper tightly stranded conductors.

High-density circular stranded pure copper cores with DC resistance strictly controlled below the national standard upper limit. This ensures stable continuous current carrying capacity in short-to-medium distance building emergency power supply; low conductor resistance prevents voltage deviations in fire pumps, smoke exhaust fans, emergency elevators, and lighting loads. The tight stranding reduces the overall cable diameter, saving construction teams space for conduit and cable tray layouts. The raw materials are 100% new oxygen-free copper, without any recycled copper, ensuring consistent conductivity across all production batches.

• Multi-Layer High-Temperature Mica Fire-Resistant Wrapping Tape (Core Material NH Properties)

  Continuously overlapping synthetic mica tape is tightly wrapped around each insulating core material, providing long-term fire resistance up to 950℃. Under ultra-high temperature flames, the mica material forms a stable inorganic insulating protective layer, isolating the flame from the internal copper core and preventing instantaneous circuit interruption in a fire. This inorganic fire barrier is unattainable by single-layer flame-retardant plastics in the ZC-VV/ZR-YJV series.

• Fire-Resistant Modified PVC Core Insulation Layer

  The outer layer of the mica tape is coated with a special high-temperature resistant PVC composite material, allowing for continuous operation at temperatures up to 70℃. It exhibits stable insulation performance in environments with high humidity, basement condensation, and seasonal temperature fluctuations. Combined with the mica tape, it forms a double-layer fire-resistant barrier, slowing heat penetration during fire combustion.

• Non-hygroscopic, flexible filler

  Moisture-resistant, flexible filler fills the gaps between the multi-core insulated wires, forming a neat, round cable profile. This eliminates internal air convection channels, slows heat transfer during a fire, and thus improves the overall fire resistance of bundled multi-core cables.

• Extruded PVC outer sheath

  A one-piece, seamless PVC outer sheath encases the multi-core insulation assembly, preventing indoor moisture, basement condensation, and alkaline concrete deposits from corroding the internal mica fire-resistant layer and insulating copper core. The improved anti-aging formula makes it suitable for concealed wall installations, cable trays, and indoor shaft installations.

• NH-ZR-VV: Double fire-resistant + Class C flame-retardant composite type, suitable for densely bundled emergency cable tray installation.
• Low-temperature weather-resistant modified NH-VV: Suitable for outdoor emergency pipeline installation in northern high-altitude areas.
• Reinforced moisture-proof sheath: Customized for concealed pipeline installation of fire pumps in underground garages.

• Rated AC Working Voltage: 0.6/1kV low-voltage building emergency power distribution system
• Power Frequency Withstand Voltage Test: 3.5kV, 5 minutes without breakdown or abnormal discharge
• Insulation Resistance: PVC insulation maintains stable high insulation resistance under long-term damp basement installation conditions.
• Reference Continuous Current Carrying Capacity: Fully compliant with the load design standards for fire pumps, smoke exhaust fans, emergency elevators, and emergency lighting in civil building electrical codes.

• 90-Minute Fire Resistance Performance: Meets GB/T 19665 NH Grade fire resistance standard; under continuous flame combustion at 950℃ + water spray impact conditions, the cable can maintain normal power supply for 90 minutes without open circuit or breakdown.
• Inorganic Mica High-Temperature Insulation: Mica tape will not melt or burn at ultra-high temperatures, forming a robust heat insulation layer to protect the copper core, providing crucial power supply for evacuation and fire fighting.
• Difference from ZR Grade Flame-Retardant Cables: ZR grade only prevents the spread of flames; NH grade guarantees continuous power supply during a fire, a mandatory requirement for all building fire protection lifeline circuits in national electrical fire protection codes.

• Minimum Allowable Bending Radius: 10 times the cable's outer diameter, making it more suitable for concealed wiring in narrow walls compared to armored low-voltage cables.
• Compression Resistance: Passes the national standard low-voltage cable compression test; PVC insulation and mica sheathing show no cracking or separation.
• Ambient Temperature Requirements: Standard model installation environment ≥ 0℃; Low-temperature customized version supports -15℃ installation without preheating.
• Design Service Life under Standard Indoor Concealed Installation Conditions: Over 30 years.
• Damp Heat Resistance: Passes continuous damp heat aging test; suitable for long-term damp underground garages and basement emergency piping environments.
• Chemical Corrosion Resistance: Resistant to weakly alkaline concrete sedimentation and mild indoor corrosive gas erosion.

• Residential Buildings: Dedicated main cables for fire pumps in high-rise residential buildings, emergency elevator power supply circuits in building electrical shafts, concealed cables for smoke exhaust fans and emergency lighting in underground parking garages
• Public Medical and Educational Projects: Fire safety lifeline distribution cables for Class B/C hospitals, emergency lighting and smoke exhaust circuits in school teaching buildings, buried pipeline cables for fire pumps in clinic basements
• Small and Medium-Sized Commercial Projects: Main emergency evacuation lighting lines for community supermarkets and food plazas, dedicated power cables for fire control equipment in underground shops
• Municipal Public Supporting Projects: Power supply cables for fire control rooms in community comprehensive service centers, emergency power distribution circuits for automatic fire alarms in underground parking lots

• Case 1: Fire Safety Lifeline Renovation Project for a 22-Story High-Rise Residential Community

  A county-level high-rise residential renovation project used a large quantity of NH-VV four-core and five-core series cables as dedicated concealed main lines for building fire pumps, smoke exhaust fans, and emergency elevators. The construction scenarios included concealed conduits in walls and damp cable shafts in basements, and the cables had to meet the 90-minute fire resistance time requirement stipulated by the local fire department. The multi-layer mica tape winding structure ensured stable power supply under simulated high-temperature fire tests; the complete NH fire resistance test documentation provided by our factory passed the one-time acceptance by the fire supervision and power departments. After three years of operation, no faults such as insulation layer aging due to moisture or mica layer separation occurred, reducing the community's annual labor cost for fire equipment circuit inspections by 70%.

• Case 2: Fire Emergency Power Distribution Project for a Community Comprehensive Medical Clinic

  The electrical design of a community medical and health center uniformly adopted NH-VV three-core fire-resistant cables for all basement fire pumps, corridor emergency lighting, and smoke exhaust equipment circuits. Medical buildings are classified as key public facilities for fire safety, and the power supply to medical equipment must be uninterrupted in the event of a fire. The NH-VV inorganic mica fire-resistant partition structure ensured continuous power supply to evacuation and fire-fighting equipment under flame impact; the economical PVC material effectively controlled the general contractor's electrical budget for the medical project; and the standardized complete set of fire resistance certification documents enabled the project to be completed and delivered 12 working days ahead of schedule.

• Case Study 3: Fire Control Circuit Upgrade Project in Underground Parking Lot of a Community Shopping Center

  A 9000㎡ underground parking lot for catering and retail in a community underwent a fire control circuit upgrade. NH-ZR composite fire-resistant and flame-retardant VV-type cables were laid in concealed wall conduits and cable trays. This underground parking lot is a closed fire hazard area with a dense concentration of emergency cables, requiring both fire resistance and flame retardancy. The inner layer of mica tape provides a 90-minute fire resistance guarantee, while the outer flame-retardant PVC sheath effectively limits the lateral spread of flames within the cable trays. Stable batch current carrying capacity ensures the continuous operation of fire alarm, smoke extraction, and emergency lighting equipment, thereby reducing annual fire circuit maintenance costs and potential downtime losses by more than 79%.

• Load and Transmission Distance Matching Rules: NH-VV PVC insulated cables have a long-term allowable temperature of 70℃ and are suitable for short-to-medium distance indoor emergency power transmission within 250 meters. For transmission distances exceeding 250 meters or heavy-duty central fire pump main lines operating continuously for 24 hours, voltage drop calculations should be performed, and NH-YJV fire-resistant XLPE cables should be evaluated as an alternative to avoid line overheating.
• Fire Resistance Rating Matching Standards: Standard single-core NH-VV cables should be selected for ordinary residential and small commercial buildings; densely bundled cable trays and emergency circuits in enclosed underground shopping malls should be upgraded to NH-ZR-VV composite fire-resistant and flame-retardant cables according to mandatory provisions of local fire codes.
• Laying Environment Classification Matching: Standard NH-VV cables are used for ordinary dry-type concealed indoor wall pipes; reinforced moisture-proof modified type is suitable for underground garage environments with long-term condensation; low-temperature resistant type is suitable for outdoor emergency pipe laying in northern regions.

• Ambient Temperature Control Requirements: The ambient temperature for standard cable laying shall not be lower than 0℃; in winter, low-temperature modified sheath models must be selected to prevent brittle cracking of the PVC outer sheath during bending and pulling.
• Bending Radius Limitation Standards: The bending radius for all turns, conduit installations, and junction box terminal connections must be ≥ 10 times the cable's outer diameter; forced sharp-angle bends are prohibited to avoid the risk of internal mica tape entanglement and separation, and open circuits in concealed fire-resistant circuits.
• Heat Dissipation Requirements for Parallel Bundled Laying of Multiple Cables: Sufficient heat dissipation gaps must be reserved between NH-VV fire-resistant cables laid in parallel within the cable tray; PVC insulation has lower heat resistance than XLPE, and excessive cable stacking will lead to a decrease in actual current carrying capacity and overheating risk. Use insulating barriers to separate fire-fighting lifeline circuits from ordinary power cables to prevent the spread of flames from ordinary circuits to emergency cables.
• Concealed pipe protection measures: When NH-VV passes through the building's firewall, fireproof sealing material is installed at both ends of the pipe to form an integrated fireproof isolation system; extra cable length is reserved at both ends of the fire control cabinet and pump room to facilitate future circuit maintenance and terminal replacement.

• Before the acceptance process begins, verify the batch factory inspection certificate, the third-party NH 90-minute fire resistance test report, and the copper material raw material certificate.
• After cable laying and terminal production are completed, complete the insulation resistance test and power frequency withstand voltage test.
• Check the batch fire resistance test records to ensure compliance with the mandatory requirements for fire safety supervision and filing.
• In accordance with the requirements of emergency power distribution specifications, complete reliable core wire grounding connections and test the grounding resistance to ensure compliance with the safety operation standards for low-voltage emergency power grids in civil buildings.