METHOD OF CHECKING TRACK FOR NON-OCCUPANCY Russian patent published in 2002 - IPC

FIELD: railway signaling and communication. SUBSTANCE: non-occupancy of track is judged by impulse current applied to supply end and received at receiving end of track circuit, and current from supply source at receiving end. Supply and receiving ends of track circuit are alternately changed. Difference in said currents is compared with threshold value. Track is considered nonoccupied when difference in current values at ends of track circuit alternately reaches threshold value. EFFECT: improved reliability at reduced insulation resistance. 1 dwg