TRACK CIRCUIT Russian patent published in 1998 - IPC

FIELD: railway signalling and communication; traffic interval control in railway transport and underground railways. SUBSTANCE: track circuit has signal source connected to one end of track circuit through one matching element, and receiver with track relay connected to other end of track circuit through other matching element, check supply source connected to other matching element through track relay closing contact, series-connected, first and second check relays. First check relay is placed between one and other matching elements. Track relay repeaters with independent supply source are used as check relays. EFFECT: reliability of traffic control. 1 dwg