BASIC APPLICATION GUIDELINES & PROGRAMMING
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5-30
SIG-00-22-02 JUNE 2022 (Revised September 2022)
Version: B.1
5.4
Spread Spectrum Radio
Spread spectrum radio may be used to send vital ATCS messages between locations without
the use of physical cables. The ATCS messages sent to GCP5000 (GCE) unit contain the
internal logic states of the tracks at that unit. The crossing unit evaluates the ATCS messages to
determine the real-time state of the outputs at the sending unit. Based on this evaluation, the
crossing unit determines when the crossing should be activated.
GCP5000 (GCE) units can communicate using the Ethernet to the eSSR without the use of the
WAG. The Laptop port of the CPU III is connected via an Ethernet cable to the eSSR as shown
in Figure 5-22. Note that if access is required to the laptop port for the CPU III Web UI then it is
advisable to connect the CPU to the eSSR via an Ethernet Switch.
If the GCE units are in the same bungalow, then the CPU IIIs can communicate directly via the
Ethernet, again it is advisable to use an Ethernet Switch so the Web UI can still be accessed.
Note that for units in the same bungalow, the CPU III could communicate using Echelon, the
advantage of this is that the laptop port can still be accessed via the Web UI.
Figure 5-22 Spread Spectrum Radio Connection
If an Ethernet network is available linking the GCE units in different locations, then the GCE
CPU III can communicate directly via the Ethernet, again it is advisable to use an Ethernet
switch so the Web UI can still be accessed.