Digital Block
Digital Block is used for exchanging permissions in fail safe way
for sending / receiving trains between two stations
SALIENT FEATURES
- 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
ADVANTAGES
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.
ARCHITECTURE
