YTTW Smokeless and non-toxic Flexible Mineral-Insulated Fire-Resistant Cable

High Reliability and Long Lifespan:
Constructed entirely from inorganic materials (copper, mica), resistant to aging, corrosion, and radiation, with a lifespan exceeding a century.
High overload capacity: Capable of operating at elevated temperatures and withstanding short-term overloads up to 1080°C.

Exceptional Installation Convenience (Greatest Advantage Compared to BTTZ):
Flexible structure: Can be bent and laid like ordinary cables, eliminating the need for specialized tools for complex straightening and terminal sealing.
Simple connections: Utilizes specialized stripping tools and terminals, ensuring high installation efficiency and low cost.
Versatile installation methods: Suitable for exposed, concealed, or tray installations, as well as direct burial or underwater use (with appropriate outer sheath).
Powerful Comprehensive Performance: Integrates fire resistance, waterproofing, explosion protection, radiation resistance, mechanical impact resistance, high current-carrying capacity, and excellent grounding performance.
Application Scope: Used in power distribution lines where national regulations mandate or owners require the highest level of fire safety, reliability, and maintenance-free operation, particularly in fire protection systems and critical lifeline engineering projects.

Conductor: Multi-stranded annealed copper wire (Class 2 or Class 5) with good flexibility. Cross-sectional range: 1.0 mm² to 400 mm² (single-core).
Insulation layer: Double-layer or multi-layer phlogopite mica tape winding, which is the core of its fire-resistant functionality.
Sheath: Continuously longitudinally wrapped, argon arc-welded, and corrugated copper sheath. This sealed copper tube provides mechanical protection, grounding, waterproofing, and forms a fire barrier. The "corrugated" design enhances flexibility.
Outer protective layer (optional): Depending on environmental requirements, a halogen-free, low-smoke, flame-retardant polyolefin sheath (e.g., YTTWY) can be extruded over the copper sheath to provide corrosion and insulation protection.
Rated voltage: 0.6/1 kV.
Maximum long-term operating temperature: Up to +90°C (with outer protective layer) or +250°C (without outer protective layer, with only the copper sheath exposed).
Fire resistance characteristics (core): Complies with the GB/T 19216.21 (IEC 60331) standard. Can withstand flames at 950°C to 1000°C for 180 minutes while maintaining circuit integrity under rated voltage, mechanical impact, and vibration.
Flame retardant properties: The copper sheath itself is non-combustible, and the overall cable achieves Class A flame retardancy.
Halogen-free and low-smoke: The copper sheath does not produce smoke or toxic gases. If an outer protective layer is present, it is made of halogen-free, low-smoke material.
Waterproof and moisture-proof: The copper sheath provides 100% radial waterproofing and moisture resistance, allowing short-term operation even when submerged in water.
Minimum bending radius: ≥ 2D (single-core, where D is the cable diameter) or ≥ 6D (multi-core stranded). Flexibility is far superior to BTTZ.
Grounding method: The copper sheath can serve as a grounding wire, achieving 100% grounding protection sensitivity.