ABB ETL600 - Page 7

ETL600 1KHW001489-EN ABB Switzerland Ltd
3.6.6. Performance criteria.........................................................................3-66
3.6.6.1. General ............................................................................................3-66
3.6.6.2. Transmission time ............................................................................3-66
3.6.6.2.1. Nominal transmission time (T0) .......................................................3-67
3.6.6.2.2. Maximum actual transmission time (Tac).........................................3-68
3.6.6.3. Security ............................................................................................3-68
3.6.6.4. Dependability ...................................................................................3-69
3.6.7. Operating principle ...........................................................................3-71
3.6.8. Functional description ......................................................................3-72
3.6.8.1. General ............................................................................................3-72
3.6.8.2. Speech bandwidth............................................................................3-73
3.6.8.3. Guard signal.....................................................................................3-73
3.6.8.4. Command signals ............................................................................3-74
3.6.8.4.1. Dual-tone principle ...........................................................................3-74
3.6.8.4.2. Trip frequencies ...............................................................................3-75
3.6.8.4.3. Command assignment to trip frequencies........................................3-76
3.6.8.5. Boosting ...........................................................................................3-76
3.6.8.6. Input/Output Command Handling.....................................................3-77
3.6.8.6.1. General ............................................................................................3-77
3.6.8.6.2. Tx Input Command Delay ................................................................3-78
3.6.8.6.3. Tx Input Command Prolongation .....................................................3-78
3.6.8.6.4. Tx Trip Duration Monitoring..............................................................3-79
3.6.8.6.5. Rx Output Command Duration.........................................................3-79
3.6.8.6.6. Rx Output Command Prolongation ..................................................3-79
3.6.8.6.7. Rx Trip Duration Monitoring .............................................................3-79
3.6.8.7. Start Inputs.......................................................................................3-80
3.6.8.8. Unblocking .......................................................................................3-80
3.6.8.9. Command Outputs During Link Failure............................................3-81
3.6.8.10. Tx Command Acknowledge .............................................................3-82
3.6.8.11. Rx Guard Signaling ..........................................................................3-82
3.6.8.12. Blocking of AGC...............................................................................3-82
3.6.8.13. Cyclic Loop Test...............................................................................3-82
3.6.8.14. Manual Loop Test ............................................................................3-84
3.6.8.15. Local Test Mode...............................................................................3-84
3.6.8.16. Command Counters .........................................................................3-84
3.6.8.17. Alarms Sources................................................................................3-85
3.6.8.18. Alarm / Warning Contacts ................................................................3-86
3.6.8.19. Interference in Speech Band............................................................3-87
3.6.8.20. Compatibility with Inband Modem Signals .......................................3-87
3.6.8.21. 3 APLC in 8 kHz Operating Mode with NSD600 ..............................3-87
3.7. Event Recorder...............................................................................3-87
3.7.1. General ............................................................................................3-87
3.7.2. NSD600 Command Events ..............................................................3-88
3.7.3. Alarm, Warning & Manipulation Events............................................3-89
3.7.4. Upload events ..................................................................................3-89
3.7.5. Upload counters ...............................................................................3-90
3.7.6. Reset counter...................................................................................3-90
3.7.7. Set clock...........................................................................................3-90
3.7.8. RTC synchronization from an external clock....................................3-90
3.7.9. Views................................................................................................3-91
Contents November 2005 III