煤矿井下变电所安装使用检漏继电器以后,当低压电网绝缘过低、人身触电发生危险、出现漏电故障等情况时,井下变电所低压总开关自行跳闸,对供电可靠性、安全性起到了很大作用。但是,安有检漏继电器的低压总开关跳闸并不只是漏电引起,当低压电网过负荷电流值超过总开关整定值时,总开 Underground mine substations installed using the leak detection relay, when the low-voltage power grid insulation is too low, the risk of personal electric shock, a leakage fault occurs, the underground substation low voltage main switch trips, power supply reliability, safety played Great effect. However, there is a leak detection relay low voltage main switch trip is not only caused by leakage, when the low voltage power grid overload current value exceeds the total switch setting, the total open