Fire retardant cables refers to the cable in which the sample is burned under specified test conditions and the flame spread is only within a limited range after the test fire source is removed, and the residual flame or residual burning can be extinguished by itself within a limited time. The basic characteristics are: in the case of fire may be burned out and cannot run, but can prevent the spread of fire. Generally speaking, the wire in case of fire, can limit the combustion in the local scope, do not produce spread, keep all kinds of other equipment, avoid causing greater losses.
Single of multi-wire conductors of plain copper wires, PVC core insulation, cores twice concentrically according to VDE 0293, common core sheathing, outer sheath of PVC standard colour black, fire retardant cables. AC acbles
Minimum bending radius for single core : 15 x outer diameter
Minimum bending radius for multi core : 12 x outer diameter
0.6/1kv power cable yjv:
According to VDE 0295 / IEC 60228
re = round conductor, single wire
rm = round conductor, multi wire
sm = sectorial conductor
General people are easy to confuse the concept of flame retardant cable and fire retardant cable, although flame retardant cable has many advantages more suitable for chemical enterprises, such as low halogen, low smoke flame retardant, but in general, fire retardant cable can replace flame retardant cable, and fire retardant cable can not replace fire retardant cable.
The principle of fire retardant cables is different from that of flame retardant cable. The flame retardant principle of halogen-free cable depends on the flame retardant effect of halogen, and the flame retardant principle of halogen-free cable depends on the precipitation of water to reduce the temperature to extinguish fire baking. Refractory cable depends on the refractory and heat-resistant characteristics of mica material in refractory layer to ensure that the cable can work normally in case of fire.
The basic structure of flame retardant cable is:
(1) The insulation layer is made of flame retardant material
(2) The sheath and outer protective layer are made of flame retardant materials;
(3) The belt and filling are made of flame retardant materials.
And fire-resistant cable is usually in the conductor and insulation layer between the addition of a fire-resistant layer, so in theory can add fire-resistant layer in the structure of fire-resistant cable, the formation of both fire-retardant and fire-resistant cable, but in practice there is no need for this.
Because of the refractory layer of the refractory cable, it usually uses multiple layers of mica tape directly wrapped on the wire. It can be burned for a long time, even if the polymer where the flame is applied is burned, it can keep the circuit running.