GOST R IEC 61557-7-2009 电压范围为1000Va.c.和1500Vd.c.的低压配电系统电气安全测试,测量设备,或防护措施监测设备第7部分相序
Low voltage distribution systems up to 1000 V a.c. and 1500 V d.c. Electrical safety. Equipment for testing, measuring or monitoring of protective measures. Part 7. Phase sequence