Abstract:The drop arrester is a combination of detachable arrester and drop type fuse. In addition to the over-voltage protection of traditional arrester, in case of abnormal fault, the power frequency short-circuit current makes the detachable move, and the grounding end automatically detachable ,which can prevent further expansion of the accident and make maintenance more convenient. This paper introduces the application and maintenance precautions of drop arrester in 6Kv powder supply line to improve the reliability of line power supply.