Siemens SIMEAS-Hub 7KE6000-8AD /CC, Руководство по эксплуатации

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SIMEAS-Hub English
E50417-K1074-C299-A1 33
Range of Application
A SIMEAS-Hub is used to connect several segments to one another. The SIMEAS-Hub
transfers each signal to the connected segments. (10Base-T/ 10Base-FL). In addition, the
SIMEAS-Hub can be used for signal regeneration (repeater function).
No software components are required to operate the SIMEAS-Hub. No parameterization is
required.
Characteristics
The SIMEAS Hub is a hard-wired and tested functional unit. It is provided with a snap-on
mounting device for a 35 mm DIN rail (DIN EN 50022) and with screw-type terminals for safe
connection of the auxiliary power supply. The 10Base-T cables are connected to the RJ45
sockets provided. The fibre-optic channel is connected by F-SMA (screw-type) terminals.
The FO signals transmitted by the 10Base-FL components are not compatible to 10Base-FP
or 10Base-FB standard. The individual 10Base-F standards can only be physically connect-
ed by an appropriate repeater.
Working on the physical layer, the repeater ignores all high-level protocols and merely
regenerates the signals of the bit streams; therefore, it cannot be used to connect different
methods of access (e.g. Ethernet
↔
Token Ring).
Per IEEE 802.3 specifications, there can be no more than four repeaters linked in cascade.
This results from the runtime behaviour of the individual components. The maximum runtime
defined in the standard is 576 bit periods, and exceeding it causes the check mechanism to
fail.
The path between any two stations cannot incorporate more than four repeaters if two of the
five segments are of the IRL (Inter Repeater Link) type. When there are no IRL, the
maximum number of segments/repeaters between two stations is three if the stations are not
separated by bridges.
Note
You will find an explanation of the technical terms in chapter Glossary,
on page 48.