Specifications

RailCorp Engineering Manual — Signals — Equipment Manual
Cerberus Level Crossing Monitor Field Equipment Manual TMG E1261
© RailCorp Page 64 of 89
Issued August 2012 UNCONTROLLED WHEN PRINTED Version 2.1
6.1.2.3 Variable Types
The level crossing monitor supports the following variable types:
• Input
• Output
• Intermediate
• Special Intermediate
• Timer
• Special Timer
• Lamp
• Battery
An input variable directly reflects the state of a digital input.
An output variable directly reflect the state to which a digital output is set.
An intermediate variable is an internal state of the level crossing monitor which is
controlled by a logical relationship of inputs and outputs.
A special intermediate variable is an internal state of the level crossing monitor which is
directly controlled by or is used by the level crossing monitor software.
An timer variable is an internal state of the level crossing monitor which is controlled by a
logical relationship of inputs and outputs and the length of time the state is maintained.
An special timer variable is an internal state of the level crossing monitor which is
controlled by a logical relationship of inputs and outputs and the length of time the state is
maintained and is directly used by the level crossing monitor software.
A Lamp variable reflects the state of the level crossing highway lamps.
A Battery variable reflects the state of the level crossing battery.
6.1.2.4 I/O List
The I/O list is a text file that lists each variable, allocates is I/O bit and declares its types.
Inputs and Outputs are declared in the form:
• name board bit
where
name is the input or output variable name.
board is 0 for all level crossing monitors.
bit is in the input or output bit number.
Intermediate variables are declared in the form:
*name1
*name2
where
*name1 is the variable name of the first intermediate variable.
*name2 is the variable name of the second intermediate variable.