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A051110
Fig. 6.3.2.-1
Star topology
Switch N is referred to as the
“
backbone
”
switch, since all the other switches
uplink to it in order to form a star configuration.
This architecture is recommended for medium or large plants, especially if
they are already organized in subsystems (example: one subsystem for each
switch gear).
Number of devices for subnet
The number of devices per subnet is limited. The limitation is set
to 256 devices. A practical subnet size should be defined by the
application and should have a size of approximately 10 devices.
In case a GSM Modem is connected, one device per total
network is sufficient.
6.3.3.
Example of star topology with REF 542plus
WebREF is particularly suitable for low-end solutions. The Fig. 6.3.3.-1
shows a typical architecture for low-end systems based on a single network in
star-topology.
Not all depicted devices are mandatory. Example: for an unmanned plant the
operator PC is not mandatory and a laptop can be used only for service,
maintenance, and so on, while the modem sends all information to a remote
control room.
34
REF 542plus
Multifunctional Protection and Switchbay
Control Unit
Installation Manual for Web Interface
Installation manual
1MRS755865