Research on online monitoring of arrester

State Grid Corporation of China(SGCC) proposed to build the unified strong smart grid with Chinese characteristics, that is the maintenance of electrical equipments has been gradually breaking human-controlled mode, transforming into smart mode and real-time monitoring of various equipments in substation. Besides, the condition intelligence judgment is one of center links. And the zinc oxide arrester is one kind of important overvoltage protector. Because of the superior nonlinear and protective value, it has been widely used in power system. However, the zinc oxide arrester doesn´t have the discharge gap, the valve will gradually deteriorate in the effect of long-term running voltage or the arrester will be affected with damp for itself bad structure. These will cause the arrester´s leakage current to increase, or cause the electric operational accident for the thermal runaway in critical condition. The traditional method is manual periodic patrol, inspection and transcript. It´s not convenient to use and manage which makes operators to do much more and inefficient. What´s more, it can´t grasp the safe state of the arrester promptly and accurately. This article studies one kind of system to real-time acquire, transmit, preserve, manage and share the information such as the zinc oxide arrester´s leakage current, the lightning frequency and timing. And form an information management system of the zinc oxide arrester´s leakage current. All the related personnel can inquire the state of all the zinc oxide arrester, of course, it increases the work efficiency. Compared with other methods, this system has the simple structure and dependable performance, and can be used in the substation of strong interference of electromagnetic field.