For the long-term working temperature of wire and cable core, rubber insulation is usually 65 ° C, PVC insulation is 70 ° C, XLPE insulation is 90 ° C; short circuit (maximum duration not exceeding 5 s) the maximum allowable conductor Temperature: 160 ° C for PVC insulation and 250 ° C for XLPE insulation.
First, the difference between XLPE cable and PVC cable:
1. Low-voltage cross-linking (XLPE) cables have developed rapidly since they were put into use in the mid-1990s and currently account for half of the market share with polyvinyl chloride (PVC) cables. Compared with PVC cable, cross-linked cable has higher current carrying capacity, stronger overload capacity and longer service life (the thermal life of PVC cable is generally 20 years, while the thermal life of XLPE cable is generally 40 years); When PVC burns, it will decompose and release a lot of black smoke and toxic gas. While XLPE will not produce halogen toxic gas when burning, the superiority of cross-linked cable is increasingly recognized by the design and use departments.
2. Ordinary PVC wire and cable (insulation and sheath) burns quickly and accelerates the fire. It will lose the power supply capacity after 1~2 minutes. The black smoke released by combustion decomposition can reach the level of five fingers, which makes it difficult for people to breathe and evacuate. . More seriously, PVC will decompose and release highly toxic and corrosive halogen gases such as hydrogen chloride (HCL) and dioxins, which are the main cause of death in fire (80% of fire death factors) and become thin. The hydrochloric acid conductive film adheres to the electrical equipment, which seriously reduces the insulation performance of the equipment and forms a secondary disaster that is difficult to remove.
