Train degradation operation method, OC, TACS system and medium

The invention discloses a train degradation operation method, an OC, a TACS system and a medium, and the method comprises the steps: determining a final position and a first advancing direction of a train before communication interruption when the communication interruption between the OC and the train is determined; determining a first manual path area corresponding to the train according to the final position and a first positioning point in the first advancing direction; the first positioning point is determined according to the type of a track where the train is located; position locking is conducted on all turnouts arranged in the first manual path area, and then all turnout signal machines in the first manual path area are made to conduct displaying according to the corresponding turnout positions so that a train can run in a degraded mode to pass through the turnouts in the first manual path area according to the display states of the turnout signal machines. According to the invention, the safe operation of the degraded train is ensured, the cost is saved, and the operation efficiency is improved.