Fire-resistant cable is a type of cable designed to ensure that, even when exposed to flames, the circuit remains free from short-circuit or open-circuit faults and continues to operate normally for a specified period. Unlike standard flame-retardant cables, fire-resistant cables are capable of continuing to transmit electrical energy during a fire, thereby facilitating firefighting efforts and minimizing losses. Their fire-resistant performance complies with GB/T 19666-2019, *General Principles for Flame-retardant and Fire-resistant Wires, Cables, or Optical Cables*, and XF 306.2-2007, *Classification and Requirements for Flame-retardant and Fire-resistant Cables—Part 2: Fire-resistant Cables*. The use of this product significantly enhances fire safety and emergency rescue capabilities in critical environments such as high-rise buildings, subway systems, and power stations.

Operating Characteristics

1. Rated Voltage Uo/U: 0.6/1 kV and below.

2. Cable Laying Temperature: ≥ 0°C.

3. Maximum Rated Temperature of Cable Conductors: 70°C for PVC-insulated cables; 90°C for XLPE-insulated cables.

4. Maximum Temperature of Cable Conductors During Short Circuit (maximum duration not exceeding 5 seconds): 180°C for PVC-insulated cables; 250°C for XLPE-insulated cables.

5. Under rated voltage, cables classified as Class I–IV can maintain normal operation for a continuous duration of 90 + 15 minutes (fire exposure time + cooling time) when exposed to a flame temperature of 750°C–800°C; cables classified as Class IA–IVA can maintain normal operation for the same duration when exposed to a flame temperature of 950°C–1000°C.

6. For Low-Smoke, Halogen-Free Fire-Resistant Cables: pH value > 4.3; Conductivity ≤ 10 µS/mm; Smoke Toxicity Index ≤ 5.

Bending Radius: Identical to that of the corresponding standard cable types.

Main Electrical Performance

Identical to the corresponding standard cable models with a rated voltage of 0.6/1 kV and below.

Model Designations and Names for Fire-Resistant Cable Series

The model designation for flame-retardant wires and cables consists of two parts: a code representing the product's combustion characteristics and the model designation of the corresponding wire or cable type.