ABB AC500-S Safety User Manual page 78

AC500-S Safety Modules
DI581-S digital safety input module > Functionality
DANGER!
After discrepancy time error, the relevant channels are passivated. As soon as a valid sensor state is
observed (equivalent or antivalent, depending on the selected mode), reintegration request status bit
for the given channel becomes TRUE. You can acknowledge an error using acknowledge reintegration
command bit for the given channel. This can directly lead to the machine start, because both TRUE –
TRUE and FALSE – FALSE are valid states for equivalence and TRUE – FALSE and FALSE – TRUE
are valid states for antivalence.
Make sure that such behaviour is acceptable in your safety application. If no, then you can use either
included PLCopen Safety POUs for 2 channel evaluation in your safety programm or write your own
POUs for 2 channel evaluation on SM560-S Safety CPU.
Fig. 17: 2 channel equivalent mode implemented in DI581-S
78 AC500-S 30.03.2017