How to distinguish between fire-resistant cables and flame-retardant cables

　　Fire-resistant wires and cables are generally divided into two types: fire-resistant wires and cables and flame-retardant wires and cables. They are the general term for wires and cables with fire-resistant properties. The following introduces how to distinguish between these two types of cables!
　　I. First, let's talk about fire-resistant wires and cables
　　According to the national experimental standard (GB12666), fire-resistant cables are divided into two grades: NHA and NHB; in general product naming, NHA is usually represented by GNH, commonly known as Class A fire-resistant cable. NHB is represented by NH in general fire-resistant products.
　　Fire resistance refers to the ability to maintain operation for a certain period of time under flame combustion, that is, to maintain the integrity of the circuit. This type of cable has the ability to supply power for a certain period of time in a flame.
　　Fire-resistant cables are actually another type of fire-resistant cable. It is made of copper as the conductive core, seamless copper tube as the sheath, and inorganic mineral magnesium oxide as the insulation material!
　　Since the whole is made of inorganic materials, the entire fire-resistant cable does not burn or spread. And it can withstand burning. Experiments have shown that: burning in a flame of 800～900℃ for 2 hours, the cable has been operating normally, and it remains intact and continues to operate normally after burning in a 1000℃ flame for 30 minutes. The general normal operating temperature is 250℃, and it can operate safely and reliably.
　　Fire-resistant cables can continue to work (transmit current and signals) in the event of a fire, and whether they spread or not is not under review. Flame-retardant cables stop working quickly in the event of a fire, and their function is to be flame-retardant and not spread and self-extinguishing. Fire-resistant cables maintain normal operation for 90 minutes in a flame of 750～800℃.
　　II. Next is flame-retardant wire and cable
　　According to the national experimental standard (GB12666), flame-retardant cables are divided into three grades: ZRA, ZRB, and ZRC. In general product naming, ZRA is commonly known as high flame-retardant cable or oxygen-barrier cable or high flame-retardant oxygen-barrier cable. ZRC is represented by ZR in general flame-retardant products.
　　Flame retardancy refers to hindering and delaying the spread of flames along the wires and cables, preventing the fire from spreading. This type of cable has self-extinguishing properties after catching fire.
　　The oxygen barrier flame-retardant technology mainly fills a layer of inorganic metal hydrate between the cable insulation core and the cable outer sheath. It is a non-toxic, odorless, halogen-free white gel. The oxygen barrier flame-retardant cable can be used for low, medium, and high-voltage power cables, control cables, and communication cables without changing the cable structure and original material parameters, and makes the cable flame-retardant Class A.
　　Halogen-free flame-retardant cables have the advantages of low toxicity, low smoke, and no halogens compared to halogen-containing flame-retardant cables. The flame retardancy level is not high, basically Class C. The reason is that the oxygen-consuming fire extinguishing efficiency of halogen free radicals is greater than the efficiency of the degradation temperature of non-halogenated flame retardants.
　　Flame-retardant cables maintain the electrical and physical and chemical properties of ordinary cables while having self-extinguishing properties, that is, they are not easy to burn, or when the cable catches fire due to its own reasons or is ignited by an external fire source, the cable will no longer continue to burn after the fire is extinguished, or the burning time is very short, or the spread length is very short.