METHOD OF AND SYSTEM FOR DETERMINING AND INDICATING ELECTRIC STATE OF FLASHOVER TYPE CUT-OUTS

摘要

The tracks of d.c. railways (rail earth) used to conduct the current must be electrically insulated from earth potential. At places where the potential difference between the rail earth and earth potential can reach unacceptable levels, voltage flashover fuses are fitted for protection against dangerous body currents. The condition of these fuses must be continuously monitored so that those which have blown may be replaced immediately. This is at present done by regular track patrols. According to the invention, the potential difference between the rail earth (3) and the earth potential (4) is detected by a reporting device (5) and the condition with the appropriate address is transmitted to an evaluation device and stored therein. If a fuse (2) has blown, the reporting device (5) sends an error message to the evaluation device so that the fuse (2) concerned can be properly replaced. The ease of fitting of the reporting device (5) and the use of radio transmission facilities make it possible to apply the system of the invention directly to existing fuses (2), thus permitting the economical and permanent monitoring of the condition of the fuses (2).