D Glossary - Siemens SICLOCK TC 400 Operating Instructions Manual

Glossary
Alarm
Alarms are events with coming and going status.
See Persistent message.
Plant central clock
The plant central clock is the central component for the time synchronization of
plants. It synchronizes all time components of the plant via its interfaces.
Plant components, automation units, computers
Plant components is the general term for the devices that have to be synchro-
nized. Depending on the degree of detail they can also be called automation units
or computers.
Typical networked plant components are, for example, PCs, SIMATIC S7.
Typical non-networked plant components are, for example, protective relays, fault
recorders.
Archive
The archive contains relevant events with additional information from the device.
Searches can be performed for specific events in the archive with a filter.
See Filter.
Atomic time (TAI)
The atomic time is defined in standards of some protocols (PTP, PTCP) as time
domains. A calendar of leap seconds is required for the calculation of the atomic
time.
Authorization
In order to be able to change parameter entries in the device using the configura-
tion tool, the user must log on to the configuration tool with a password. There are
various authorization levels.
The current authorization status is displayed in the password entry field in differ-
ent colors; red is the lowest authorization level.
See Password.
© Siemens AG 2007 All Rights Reserved
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SICLOCK TC 400
D
D-123