Home / Standards / GB/T 18891-2009 GB/T 18891-2009 Abolished Identification by hour numbers of the phase conductors of 3-phase electric systems 三相电力系统相导体的钟时序数标识 Standard Type GBT ICS 29.020 CCS K09 Status 废止 Issue Date 2009-05-06 Implementation 2009-11-01 Responsible Dept 国家标准委 Drafting Unit N/A