
WAYSIDE INTERFACE APPLICATION
_________________________________________________________________________________________________________
5-1
SIG-00-07-11 SEPTEMBER 2012 (REVISED OCTOBER 2019)
Version No.: B.2
SECTION 5
WAYSIDE INTERFACE APPLICATION
5.0
WAYSIDE INTERFACE APPLICATION
5.1
INTRODUCTION
Positive Train Control (PTC) is an automated control system for railways that ensures the safe
operation of trains using data communication between the various control entities that make up
the system. As part of a PTC system, the VIU-20 interfaces with the signals and switches on an
interlocking and compiles vital messages concerning signal aspect and switch position using the
Wayside Interface Unit (WIU) application. These messages are passed through the ITCM
system for transmission to any locomotive within radio range.
Figure 5-1 VIU Monitoring Switches and Signals in an Interlocking
5.2
WAYSIDE INTERFACE SYSTEM
A VIU Wayside Interface System consists of three major components:
•
VIU (WIU)
•
Interoperable Train Control Messaging (ITCM)
•
Train Management Computer (TMC)
NOTE
The VIU-20 contains no replaceable parts. If the unit fails, replace the
VIU-20 but leave the ECD/Power connector installed. The newly
installed VIU-20 will obtain its configuration from the ECD.
Switch
Input
Lamp
Input
VIU
(WIU)
VIU
(WIU)
VIU
(WIU)
LAN
LAN
VIU
(WIU)
11-11_ITC_WSDE_INTRFC
08-05-11
Ethernet
Switch
Input
ITCM = Interoperable Train Control Messaging System
ITCM