RK-500 Track circuit

The RK-500 is an audio frequency track circuit without connection or JL that is designed to detect the presence of a train and send information to the train with highest safety factor. These track circuits can have a length between 50 and 350 meters and also have the ability to increase the length up to 900 meters if needed. To provide the above functions the circuit units are divided into two categories: indoor unit and outdoor unit. The distance between the outdoor equipment and transmitter and receiver associated with them is about 4 km if required by the employer.

Due to the fact that the correct receiving of information by the train depends on the direction of the train in direction of the track transmitter, and since the train may need to move on both sides of the track, in the RK-500 track, there are two sides of the track using relays called DR relays that is possible to move the location of the transmitter. In the track where this feature is considered, the direction is changed by installing DR relays that operation is under the authoring of interlocking.

RK-500 circuit frequencies

By having 8 nominal frequencies for the tracks, this system has provided the maximum utilization of the lines. The RK-500 track circuit is composed of various units that realize the functions of the system. Some of the units are installed inside the room and another part is installed in the area. These units include transmitter (TX), receiver (RX), track relay (TR), direction relay (DR), power supply (PSU), adaptation (MU), adjustment (TU) and types of bonding (Z-bond , α-bond and Shunt-bind).