STC SmartScanIS, Руководство пользователя

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EUD-2016026-00 Rev.2, SmartScanIS User’s Guide for Union Pacific, 14 January 2021
77
4.7.5 Universal Transient Barriers
On the DIN rail are industrial grade surge suppressors (aka universal transient barriers or
UTBs). They protect the system from voltage surges from the shielded temperature probe,
telephone, transducers, and dragging-equipment detector. At sites with wide-load, high-load,
or high-wide detectors, the system will also be protected from voltage surges from these
devices.
The UTBs are capable of suppressing damaging electrical transients and surges, which can
be induced onto signal lines by lightning. Here is a list of signals that pass through the UTBs
on the DIN rail before entering the rest of the SmartScanIS enclosure.

Gating transducer TO1

Gating transducer TO2

Advance transducer ADVANCE , if used

Dragging-equipment detector, DRAGGER

Shielded temperature probe TEMP PROBE , which uses two UTBs

High-load detector HIGH , if used

Wide-load detector WIDE1 , if used

Wide-load detector WIDE2 , if used

Telephone line TELCO
Each UTB is mounted vertically on a DIN
rail. Shown to the left are two views of the
same UTB.
As you can see, there are two tiers of
connectors (one above the other) on each
side of the UTB. Starting from the top, the
connectors on the first and fourth rows are
lower than those on the second and third
rows.
The equipment listed above is wired to the
third row of connectors.
Also on the DIN rail, but not protected by UTBs, are connections for the track circuit. Before
entering the rest of the SmartScanIS enclosure, the wiring from the track circuit is protected by
a three-terminal arrester. Therefore, it doesn't need UTB protection.