Process Bus - ABB RELION REX640 Technical Manual

Section 3
Basic functions
3.2.3
84
• Via an external redundancy box (RedBox) or a switch capable of connecting to
PRP and normal networks
• By connecting the node directly to LAN A or LAN B as SAN
• By connecting the node to the protection relay's interlink port
HSR
HSR applies the PRP principle of parallel operation to a single ring, treating the two
directions as two virtual LANs. For each frame sent, a node, DAN, sends two frames,
one over each port. Both frames circulate in opposite directions over the ring and each
node forwards the frames it receives, from one port to the other. When the originating
node receives a frame sent to itself, it discards that to avoid loops; therefore, no ring
protocol is needed. Individually attached nodes, SANs, such as laptops and printers,
must be attached through a "redundancy box" that acts as a ring element. For example,
a REX640 protection relay with HSR support can be used as a redundancy box.
Each protection relay has a 50-μs store-and-forward delay. To fulfil
the performance requirements for fast horizontal communication for
protection applications using GOOSE and SMV, the ring size is
limited to 30 protection relays.
COM600
Redundancy
Box
GUID-ED51EEB9-98EB-4D4D-B0F8-BB965927FAF4 V2 EN
Figure 9: High-availability seamless redundancy solution

Process bus

Process bus IEC 61850-9-2 defines the transmission of Sampled Measured Values
within the substation automation system. International Users Group created a
guideline IEC 61850-9-2 LE that defines an application profile of IEC 61850-9-2 to
facilitate implementation and enable interoperability. Process bus is used for
distributing process data from the primary circuit to all process bus compatible
devices in the local network in a real-time manner. The data can then be processed by
any protection relay to perform different protection, automation and control functions.
SCADA
Redundancy
Box
IEC 61850 HSR
1MRS759142 C
Devices not supporting HSR
Ethernet switch
Redundancy
Box
Technical Manual
REX640