电力设备接地引下线导通测试方法的探讨

测量接地引下线与接地网及相邻设备间的导通电阻,不仅可以发现设备接地引下线电气接触不良,而且可发现接地网的局部缺陷,类工频法是目前测试导通电阻主要方法。指出了导通电阻测试需注意参考点(基准点)选择,接触电阻及现场干扰的影响。测试仪器测试宜选用采用精度高、输出电流较大、复测性好的专用测试仪器专门仪器(测试)。进行接地引下线导通电阻测试时,应按变电所接地网运行时间长短,按室内、室外接地引下线在规程基础上合理安排测试周期。导通电阻测试数据应采用比较的方法,比如与历史数据比较、横向比较等方法。

Discussion on the Continuity Testing Method of Power Equipment Grounding Lead

Through measuring the continuity resistance between grounding lead and the grounding net as well as the neighbor equipment,it can be not only to discover the bad electric contact of the equipment grounding lead,but also to discover the partial defects of the ground connection net.Simulating power frequency method is the main method to test continuity resistance at present.It is indicated that continuity resistance test need to pay attention to the selection of reference point(datum mark),the effect of the contact resistance and on-site interference.The test instruments with high precision,larger output current and better re-test quality should be used.In grounding lead continuity resistance test,the test cycle should be arranged according to the indoor and outdoor grounding lead and the duration of runtime and based on the regulations.The comparison method should be adopted for continuity resistance test data,such as comparison with historical data,transverse comparison and so on.