LST EN 61557-9-2015 交流1000V和直流1500V以下低压配电系统电气安全. 防护措施的试验, 测量或监控设备. 第9部分: IT系统中的绝缘故障定位设备(IEC 61557-9-2014)
Electrical safety in low voltage distribution systems up to 1 000 V a.c. and 1 500 V d.c. - Equipment for testing, measuring or monitoring of protective measures - Part 9: Equipment for insulation fault location in IT systems (IEC 61557-9:2014)