Device for monitoring the level and the variation of an electrical signal of a track circuit

摘要

The invention monitors the electrical signal of a track circuit, with the assistance of three converters (U1, U2, U3), in order to determine whether initially solely a predetermined reference level is reached when an associated track section is cleared and whether both the reference level and also a predetermined reference variation are subsequently present. Only if these conditions to be expected at a free track section are fulfilled do pulses derived from a clock generator (TG) pass to further processing devices. <IMAGE>