I'm planning to connect a security relay to Safety I/O board (A20B-3300-0690). Connecting the output from the card to the relay is straight forward.
However, I would like to connect a feedback to verify that the neither of the relays sticks to be compliant to the machine directives.
I planned to use the NC connector on the security relay and the "Safe I/O consistency check" to verify that an input from the NC is the same as the output but inversed.
The security inputs are double channel and security relays have typically only one NC connector.
The security inputs uses inversed polarity so I can not connect the same signal to the both channels.
Does anybody know a simple way to connect this?