矿井低压电缆第四芯的合理截面

ADEQUATE CROSS-SECTION OF 4TH CORE OF LOW TENSION CABLE FOR MINE USE

煤矿井下禁止采用三相四线制系统供电，而目前矿井低压四芯电缆的第四芯截面的大小，仍参照三相四线制的使用条件执行，这就导致电缆消耗有色金属量大且使用不便。分析计算了矿井低压四芯电缆第四芯可能通过的电流，并考虑到热稳定性、机械强度等因素，提出应该生产第四芯截面为１０ｍｍ２或６ｍｍ２以下的矿井专用四芯电缆。第四芯截面的减小，为制造四芯以上电缆创造了条件，便于井下供电的远控、监视和继电保护。

It is not allowed to use three phase four core cable for power supply underground. Currently, the cross section of the 4th core of low tension cable is based on the condition of 3 phase 4 core cable. A great deal of non-ferrous metal is consumed and the cable is not easy to handle. Taking into consideration of the current, thermo-stability, mechanical strength, the cross-section of the 4th core should be 10 mm2 or 6 mm2 for special mine use cable. Reduced cross-section of the 4th core has created condition for making 4 core or more cable, and it is easy to achieve remote control, monitoring and protection of power supply.