Digital Block System

• Completely safe – CENELEC SIL-4 certified
• High reliability – Inbuilt 2 out 3 Architecture
• Improved availability
• Woks with variety of media – OFC (dark fibre) / Copper cable / E1 Channel / Voice channel – equipped with redundancy of media selection
• Protection against surges
• Redundant power supply
• Flexible – Fit for DC/AC/Diesel traction territories
• Easy to deploy – Embedded, prewired modules
• Least operations – Saves operations time
• Fast operations – Takes few seconds
• Easy to maintain & troubleshoot – Completely electronic, deskilling of trouble shooting with extensive diagnostics
• Reduced cost of maintenance – By Remote Condition Monitoring

Operational Benefits

• Automatic TOL – block failure due to premature TOL operation eliminated.
• Automatic Line Close – Elimination of operator involvement results in time saving and immediate block closure.
• Block closing provision after push back operation, avoids block failure for next train.
• Audio-visual alarms on section occupancy and clearance.
• There is no block length limitation as equipment supports OFC.

Maintenance Benefits

• No periodic over hauling as there are no mechanical parts.
• Less number of relays used – improved reliability.
• Error code displayed numerically for ease of understanding.
• Status of all relays indicated by LED – reduces MTTR.
• Diagnostic LED indications provided on the PCB facia makes troubleshooting easy.
• Sufficient space provided in the equipment rack for keeping spares to reduce MTTR.

Safety

• 2 out of 3 Architecture ensures safety as well as availability.
• Inclusion of watch dog and mine fields for controlled software flow.
• Bi-state and de-bounce validations for inputs.
• Independent 2 out of 3 Architectural Voter card for placing validated outputs.
• Critical Power Control module using twin relays for assisting safe shutdown.
• Latching nature of TGTR and TCFR QL1 Type relays is tested for its every operation.

Additional Benefits

• Block instrument clock is synchronized with GPS.
• Extra Modem is provided for communication between data logger and Digital Block.
• Industrial grade, components provided to ensure reliability.
• Communication lines and power supply lines are protected with SPDs.
• Burn-in and temperature cycle tests in the manufacturing process ensures zero fault production.
• Each processor card is provided with independent power supply system – ensures reliability.