BS 7846 F120 Armoured Fire Performance Cable

What is BS 7846 F120 Armoured Fire Performance Power Cable?

The BS 7846 F120 Armoured Fire Performance Power Cable is a premium low-voltage, steel wire armoured (SWA) circuit integrity power cable featuring Class 2 stranded copper conductors, primary mica glass tape (MGT) fire barriers, XLPE insulation, dual protective glass tape layers, and halogen-free bedding and oversheathing manufactured in accordance with BS 7846-F120 and BS 8519 Category 3 specifications. Rated at 0.6/1kV, it is designed to maintain uninterrupted power to essential emergency life safety systems during real-world building fire conditions involving active suppression and falling debris.

Unlike standard flame-retardant cables, this cable is certified to survive 120 minutes of continuous flame exposure accompanied by direct mechanical impact shocks and high-pressure water jet spraying per BS 8491. The combination of heat-resistant mica-glass barriers and low smoke zero halogen (LSZH) compounds prevents insulation breakdown and toxic acid gas generation, while the robust galvanized steel wire armour delivers essential tensile strength and mechanical crush resistance for mission-critical installations.

BS 7846 F120 Armoured Fire Performance Power Cable Construction

• Conductor: Class 2 stranded plain annealed copper conductors conforming to BS EN 60228, ensuring optimal electrical conductivity and thermal durability.
• Fire Barrier (Primary): Mica Glass Tape (MGT) wrapped over each conductor, forming an impermeable thermal barrier to sustain electrical circuit integrity during active fires.
• Insulation: Cross-Linked Polyethylene (XLPE) delivering high dielectric performance, continuous 90°C thermal endurance, and high short-circuit withstand.
• Inner Barrier & Bedding: Inner glass tape wrapping covered with an extruded Low Smoke Zero Halogen (LSZH) bedding compound.
• Armour: Galvanized Steel Wire Armour (SWA) providing heavy-duty mechanical impact protection and serving as an auxiliary earth continuity path.
• Outer Barrier & Sheath: Secondary outer glass tape barrier covered by a heavy-duty, UV-resistant black Low Smoke Zero Halogen (LSZH) outer sheath.
• Core Identification: 2 core: Brown, Blue; 3 core: Brown, Black, Grey; 4 core: Brown, Black, Grey, Blue; 5 core: Brown, Black, Grey, Blue, Green/Yellow.
• Sheath Colour: Black.

Applications

BS 7846 F120 Armoured Fire Performance Power Cables are engineered for critical emergency power distribution loops where power must be sustained for a minimum of 120 minutes during a structural fire to support occupant evacuation and fire service operations.

• Smoke Extraction & Ventilation Systems: Supplying continuous high-power feeds to emergency smoke dampers, pressurization fans, and exhaust shafts in high-rise buildings.
• Fire Suppression & Sprinkler Pumps: Direct power drops connecting emergency generators to primary fire water booster pumps and dry riser systems.
• Emergency Evacuation Lifts & Lighting: Essential three-phase power runs serving firefighter lifts, stairwell pressurization units, and central emergency lighting panels.
• High-Density Public Infrastructure: Underground rail transit stations, airport terminals, hospitals, and road tunnels requiring zero corrosive acid emissions and 120-minute Category 3 circuit survivability.

Specifications & Dimensions

The BS 7846 F120 Armoured Fire Performance Power Cable portfolio covers 2-core, 3-core, 4-core, and 5-core configurations with nominal conductor cross-sectional areas spanning 4mm² up to 400mm². Rated for an operating voltage of 0.6/1kV and continuous service temperatures from -20°C to +90°C, the cable requires a minimum installation bending radius of 8 times the overall diameter. Overall outer diameters range from 23.4mm on smaller multi-core sizes up to 82.5mm on large 4-core 400mm² assemblies, with nominal weights extending from 950 kg/km up to 21,000 kg/km. All physical dimensions, insulation radial thicknesses, galvanized steel wire armour gauges, and electrical resistance values strictly align with BS 7846, BS EN 60228, and British standards.

Standards

Design & Construction Standard: BS 7846-F120
Fire Resistance Performance: BS 8491 (120 minutes with fire, direct impact & water jet), BS 6387 CAT CWZ, BS 8519 Category 3 (120 min)
Flame Retardancy: IEC 60332-1-2, IEC 60332-3 Category C
Low Smoke Zero Halogen: IEC 60754-1/2 (Zero Halogen Acid Gas), IEC 61034-1/2 (Low Smoke Density)
Operating Parameters: Voltage Rating: 0.6/1kV; Operating Temperature: -20°C to +90°C; Bending Radius: 8 × overall diameter
Regulatory Compliance: BASEC Approved, LPCB Certified (Red Book Live), CE Marked, UKCA Marked, Low Voltage Directive 2014/35/EU, RoHS 2015/65/EU, REACH EC 1907/2006

Frequently Asked Questions

Q: What makes BS 8491 testing critical for BS 7846 F120 cables compared to standard fire-resistant cables?
A: Standard fire-resistant cables are typically tested under flame alone; BS 8491 tests the cable under simultaneous high-temperature fire, repeated direct mechanical impact blows, and high-pressure water jet spraying for a full 120 minutes, simulating real building collapse and firefighting conditions.

Q: Why does the cable construction incorporate dual glass tape barriers alongside MGT?
A: The conductor-level Mica Glass Tape (MGT) preserves electrical dielectric properties under extreme heat, while the inner and outer glass tape barriers support physical structural integrity and shield the assembly from molten slag and thermal delamination during combustion.

Q: Can BS 7846 F120 SWA cable be installed directly in outdoor or underground duct systems?
A: Yes, its heavy-duty galvanized steel wire armour (SWA) and weather-resistant LSZH outer sheath provide substantial mechanical impact resistance and environmental defense, making it suitable for cable trays, concrete risers, outdoor runs, and underground ducts.

Q: What payment terms does Huadong Cable accept for international project export orders?
A: We accept standard international commercial payment terms, including Telegraphic Transfer (T/T, with 30% advance deposit and 70% against shipping documents) and 100% Irrevocable Letter of Credit (L/C) at sight.

BS 7846 F120 Armoured Fire Performance Cable – Why Choose Huadong?

Huadong Cable Group manufactures BS 7846 F120 Armoured Fire Performance Power Cables in strict compliance with BS 7846, BS 8491, and BS 8519 standards, validated through rigorous batch testing for conductor resistance, flame resistance, and zero halogen gas emission. Utilizing high-purity electrolytic Class 2 copper conductors precision-taped with high-grade synthetic phlogopite mica glass ribbons, our cables guarantee thermal endurance during prolonged fire events. Paired with dry-cured XLPE insulation, precision steel wire armouring, and specialized zero-halogen compounds, our assemblies deliver total mechanical defense, low smoke emissions, and circuit integrity up to 120 minutes under active fire and water suppression.

With more than 20 years of precision cable manufacturing expertise, Huadong Cable Group operates advanced multi-core stranding, SWA armouring, and halogen-free extrusion lines certified to ISO 9001, CE, UKCA, RoHS, and REACH protocols. By eliminating commercial middlemen, we provide competitive factory-direct pricing, 100% Mill Test Certificates (MTC) tested in accredited testing facilities, continuous drum lengths on heavy-duty ISPM 15 heat-treated export wooden reels, and seamless door-to-port logistics for EPC contractors, fire protection engineers, and critical infrastructure developers worldwide.