SUPPLY AND IMPLEMENTATION OF TRACK CIRCUITS MRC-U ON THE SECTION TAPA-TARTU OF ESTONIAN RAILWAYS

Currently, SRPA “Impulse” supplies and implements microprocessor audio frequency track circuits MRC-U under the contract with Siemens Mobility on Modernisation of track circuits and the ALSN system under the framework of the project “Replacement of CCS systems on the Estonian Railways infrastructure” of the section Tapa-Tartu (Line 3).

In general, the scope of the project covers 90% of railway infrastructure of Estonian Railways.

Track circuits MRC-U manufactured by SRPA “Impulse” are implemented in conjugation with Trackguard SIMIS IS system manufactured by Siemens on the section Tapa – Tartu with length of 112.5 km and perform the following functions:

• monitoring of occupancy of the track sections and integrity of rail lines;
• generation of ALSN code signals.

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.