Multiple Vius In A System - Siemens VIU-20 Installation And Instruction

BASIC VIU OPERATION
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3.8

MULTIPLE VIUS IN A SYSTEM

In larger interlockings, multiple VIUs may be required to monitor all of the signal lamps,
switches, and/or defect detectors. In this case, auxiliary VIUs will send vital ATCS messages to
a Main VIU (Master). All I/O data is consolidated by the Main VIU and it transmits the
consolidated message to the on-board system and/or back office.
Please refer to Section 4 for details on setting up a multi-VIU system.
3-8
SIG-00-07-11 SEPTEMBER 2012 (REVISED OCTOBER 2019)
Version No.: B.2