TRACK CIRCUITS MRC-U ARE SUPPLIED TO DOBELE STATION OF LATVIAN RAILWAYS

SRPA “Impulse” supplied microprocessor audio frequency track circuits MRC-U within the project “Microprocessor track circuits MRC-U with ALSN functions for Dobele station” of Latvian Railways (VAS "Latvijas dzelzceļš").

MRC-U are designed to:

• monitor occupancy of the track sections and integrity of rail lines;
• generate ALSN code signals.

Main functions:

• Power supply of track circuits (audio frequency signals), measurement of currents and voltages levels.
• Generation of ALSN codes.
• Diagnostics and transmission of information about the track circuits equipment state to the higher level.
• Protection from external electromagnetic impacts (caused by atmospheric phenomena, traction currents of 50 Hz frequency etc.).
• Self-diagnostics, change to the protective state if a failure occurs.

Implementation of MRC-U will allow to:

• Exclude all relay circuits from coding of track circuits and ALSN equipment or parallel discrete interface.
• Reduce to minimum the maintenance due to stable parameters of MRC-U in case climatic conditions change.
• Optimise the process of track circuits calculation.
• Provide for a simple coupling via digital or parallel interfaces with microprocessor, relay interlocking and automatic block signalling.
• Perform continuous monitoring of cable parameters including core-to-core fault and ground fault.
• Provide for continuous monitoring of track circuit parameters including insulation failure of an insulated joint, rail integrity, and residual voltage of a receiver.
• Reduce to minimum the human factor influence due to monitoring the adjustment processes

MRC-U can be applied on main-line and industrial railways, as well as in subways.