What is flame retardant wire and cable? What is the difference between it and fire-resistant wire and cable?

Fire-retardant wire and cable (ZR)

Fire-retardant cable to maintain the electrical and physical and chemical properties of ordinary cables at the same time, with self-extinguishing, that is, it is not easy to burn, or when the cable for some reason their own fire or external ignition source ignited fire, the cable in the fire extinguished after the cable no longer continue to burn, or burning time is very short (60 minutes or less), or a short length of delayed combustion.

Because of its low cost, blocking, delaying the spread of flame along the cable, so that the fire does not expand. Therefore, it is a cable variety that is used in large quantities in fireproof cables. The cable may be burned in a fire situation and can not be operated, but can stop the spread of fire to avoid causing greater losses.

Fire-retardant cable structure and ordinary cables are basically the same, the difference is that its insulation, sheath, outer sheath and auxiliary materials (wrapping and filling) all or part of the use of flame-retardant materials.

Two, fire-resistant cable (NH)

Fire-resistant wires and cables in the event of a fire can continue to work (transmission of current and signals), its own flame retardant with or without the assessment. Flame-retardant cable in the event of a fire quickly suspend the work, its function is flame retardant and not wave can self-extinguishing; and fire-resistant cable can be in the 750 ~ 800 ℃ flame burning to maintain normal operation for 180 minutes.

Fire-resistant cable in the flame has a certain time power supply capacity, in the case of flame combustion can maintain the normal operation of the line for a certain period of time. In layman's terms, in case of fire, the cable will not burn at once, the circuit is safer.

Fire-resistant cable structure and ordinary cable is basically the same, the difference is that the conductor of the fire-resistant cable with good fire resistance of copper conductor (copper melting point of 1,083 ℃), and in the conductor and the insulation layer between the increase in fire-resistant layer. The fire-resistant layer is made of multi-layer mica tape wrapped around. Because the allowable operating temperature of different mica tape varies greatly, so the key to the fire-resistant performance of the cable is the mica tape.

Three, flame retardant wire and cable and fire-resistant wire and cable difference

1, the difference between the structure and materials

Fire-resistant cable structure and materials and flame retardant cables are not the same. The basic structure of fire-retardant cables is:

(1) the insulation layer is made of fire-retardant materials

(2) the sheath and outer jacket are made of fire-retardant materials;

(3) the wrapping and filling are made of fire-retardant materials.

And fire-resistant cable is usually between the conductor and the insulation layer and then add a fire-resistant layer, so theoretically you can add a fire-resistant layer to the structure of the fire-retardant cable, it forms both fire-retardant and fire-retardant cables, but in practice there is no need for this.

Because the fire-resistant layer of the fire-resistant cable is usually made of multilayer mica tape wrapped directly around the wire. It can withstand prolonged combustion, even if the polymer at the applied flame is burned, but also to ensure the normal operation of the line.

2, the principle of different

Fire-resistant cables and flame-retardant cable principle is different. Halogen-containing cable flame retardant principle is to rely on the halogen flame retardant effect, halogen-free cable flame retardant principle is to rely on the precipitation of water to reduce the temperature to extinguish the fire roasting. Fire-resistant cable is relying on the fire-resistant layer of mica material in the fire-resistant, heat-resistant properties, to ensure that the cable in the fire also work properly.

Fire-resistant cables can maintain normal power supply for a period of time in the event of a fire, while flame retardant cables do not have this characteristic. This characteristic determines that fire-resistant cables play an important role in modern urban and industrial buildings.

In general, fire-resistant cables can replace fire-retardant cables, while fire-retardant cables can not replace fire-resistant cables.

Fire-retardant cables are suitable for places where people are more concentrated, air density is low, and other places where the requirements for fire-retardant are high.

Fire-resistant cables are suitable for all the lines that still need to maintain normal operation in case of fire, such as fire fighting systems, emergency lighting systems, life-saving systems, alarms and important monitoring circuits in industrial and civil buildings.