2 description, Description – Siemens SICLOCK TC 400 User Manual
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SICLOCK
®
TC 400
Description
2
Modern automation systems consist of a variety of computers, controllers and
systems that exchange data with one another. For real-time operation of such
plants, it is essential that the times of all components are synchronous. This
applies especially for error tracing, when event messages receive a time stamp
and when cause and effect have to be identified through a reliable chronological
sequence.
As plant central clock, SICLOCK TC 400 supplies the various plant components
with the exact and reliable time, which is obtained from one or more external syn-
chronizations with an official or legal time, usually GPS or DCF77 radio clocks.
The time is distributed via Ethernet, and also via point-to-point outputs.
Note
Use only one device as plant central clock to supply the time to all components
throughout the plant.
Exception: redundant operation of the plant central clock.