Specifications

Engineering Standard –NSW
Signalling SMS 02
Cerberus Level Crossing Monitor Equipment
March 2005 Version 1.2 © Australian Rail Track Corporation Page 13 of 118
This document is uncontrolled when printed.
Serial Channel A Serial Channel B
9600 bps 19200 bps
8 data bits 8 data bits
1 stop bit 1 stop bit
no parity no parity
The functions available to a user are menu driven. These functions
include obtaining the event log, IO states, configuration details, and
status change times as well as conducting a remote battery test.
Some menu items are protected by a PIN number.
The PIN numbers will be common for a Region and are available
through the District Signal Engineer or Standards & Technical
Services Engineer.
2.3 Logging
Once every 0.25 seconds the Level Crossing monitor checks its
analogue inputs, digital inputs and it's digital outputs for changes. If
any changes are found then details of these changes are logged
with their date and time (to the tenth of second) of occurrence.
The log contains the last 10,000 changes. The oldest event is
automatically replaced by the next new event when the event log is
full.
The log is maintained in a non volatile storage medium (battery
backed memory). The log is still retrievable after the Level Crossing
monitor has been without power and disconnected for at least 2
years.
Changes to the state of the flasher inputs are not logged. The VIOs
used to monitor the flasher units are connected to the level crossing
monitor directly via the flasher cable (4 wires - 2 Red, 1 Blue, 1
Orange) to Input 4. This is solely to prevent wasting log space. (See
standard circuits in Appendix C)
2.4 Status Reporting
2.4.1 General
The Level Crossing monitor indicates its status locally using No
Warning and or No Fault indications on the front panel. If a warning or
fault occurs, then the No Fault or No Warning outputs turn off as
appropriate and the cause is indicated by turning on either system,
lamp, battery, or logic output as appropriate. Details of the outputs
are described in the section on digital outputs.
Monitor status changes are reported to a pre-programmed phone
number via a dial-up modem if this facility is enabled. The message
requires an acknowledgment. If not acknowledged because the
phone