Earth grid corrosion and broken point diagnosing system for large and medium-sized substations

An earth grid corrosion and broken point diagnosing system for large and medium-sized substations comprises a mobile measurement port box, a port measurement device, a mobile mainframe computer and test clamps. The utility model provides a novel diagnosing system, by performing a first wring for partial points to be measured of a substation, all the combinations of any two of the wringed points to be measured can be measured at the mobile measurement port box, process of repeated wringing can be omitted, and measurement data measured by port measurement device is transmitted to the mobile mainframe computer through a high-speed serial port. The specific circumstance of defects of each earth grid branch can be acquired by analyzing the data by the aid of diagnosing software. The earth grid corrosion and broken point diagnosing system for the large and medium-sized substations can be widely used for detecting earth grid corrosion faults of the substations which are put into operation, and especially is applicable to large substations which occupy large area and have high requirements on safety. Besides, the earth grid corrosion and broken point diagnosing system further can be applied to other systems with grounding grids such as steel, chemical industry, power plants and the like.