BECKHOFF CX50x0 - Manual (Page 40)

Notes on the documentation
38 CX50x0 - Hardware Documentation
Note
The supplement only supports CABLE REDUNDANCY
This supplement only supports cable redundancy, which means that only the cable sections
can be regarded as fail-safe, i.e. connections between the couplers.
Failures of individual terminals are not covered.
Further details can be found in the Beckhoff Information System under EtherCAT cable
redundancy.
Cases of failure
The two possible failures are described in the example below.