一、前言在国内,五十年代到七十年代初期间所建立起来的无线电实验室、计量室或整幢无线电实验大楼,建造时一般未考虑实验室用的接地装置系统,所以长期来仪器、测量设备都没有可靠接地。有时不得不采用电源中线或动力供电系统送来的作保护接零用的零线作地线,也有采用暖气管道作接地极。这 I. Introduction In China, the radio laboratory, metrology room or the entire radio experiment building built in the 1950s and the early 1970s generally did not consider the grounding system used in laboratories during construction. Therefore, for a long time, the instruments, None of the measuring equipment is grounded reliably. Sometimes have to use the power line or power supply system for protection of zero-use zero line for the ground, there are also used for heating earthing pole. This