ABB REO 517 Applications Manual page 226

&KDSWHU
Apparatus control
&RQWURO
([DPSOH
Figure 97 illustrates the above described step-by-step command execution and bay-to-
bay communication.
The example station is a double busbar with only two lines and one bus coupler. The
bus coupler also handles the busbar earthing switches.
In this station, Line 1 and Line 2 need information from the bus coupler and the bus cou-
pler need information from Line 1 and Line 2. Figure 97 illustrates the station-wide
communication. The signals not used in the figure are removed.
The bus coupler has information for two event function blocks. But for the two lines,
one block is enough.
Besides these outputs, a valid bit is available on the command function blocks.
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