Define operating mode and topology
Before making the choice of SFP, it must be clear whether the CU1521-0020 converts/branches an EtherCAT line or is used as an Ethernet media converter.
Use case | Operation mode | Active ports | Important consequence |
|---|---|---|---|
Convert or branch EtherCAT line via fiber optic cable | EtherCAT mode | X1, X2 and X3 according to rotary switch position | X3 only supports 100 Mbit remote stations; select SFPs on X1/X2 to match the remote station. |
Implement Ethernet connection via SFP | Ethernet mode | X1 and X3 | Device works as a 2-port media converter with store-and-forward and link loss forwarding. |
![]() | Decision support If an EtherCAT topology is implemented, read Putting EtherCAT mode into operation. If only one Ethernet line is implemented between RJ45 and SFP, read Putting Ethernet mode into operation. |
