ABB RET650 Technical Manual page 558

Section 16
Station communication
552
The communication is performed in parallel, that is the same data package is
transmitted on both channels simultaneously. The received package identity from one
channel is compared with the data package identity from the other channel. If the
identity is the same, the last package is discarded.
PRPSTATUS supervises redundant communication on the two channels. If no data
package has been received on one or both channels within the last 10 s, the output
LAN1-A and/or LAN1-B are set to indicate error.
Station Control System
Data
Switch A
1 2
Data
IEC13000003 V1 EN
Figure 246: Redundant station bus
Redundancy
Supervision
Duo
Data
Switch B
1 2
Data
A B
IED
COM03
PRPSTATUS
IEC13000003-1-en.vsd
1MRK 504 135-UEN A
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