ABB RELION 620 Series Technical Manual page 60

Section 2
620 series overview
54
GUID-207430A7-3AEC-42B2-BC4D-3083B3225990 V3 EN
Figure 11: HSR solution
LAN A of one device should connect to LAN B in the next device in the
ring. Do not connect LAN A to LAN A or LAN B to LAN B.
1MAC504801-IB E
620 series ANSI
Technical Manual