Beckhoff TwinSAFE logic FB

Function blocks
62 Function blocks for TwinSAFE logic components
3.5.4 Restart behavior
If all active MonIn inputs and the active EDM inputs are TRUE and the Restart signal changes from
FALSE to TRUE, the Start state (FB state 6) is assumed. The detection of a change of the Restart signal
from TRUE to FALSE triggers a check whether all MonIn inputs are still TRUE and whether the EDM
signal is still TRUE. The output is enabled if these criteria are met and the function block is not in ERROR
state.
NOTE
Restart input
The function block expects a button with make contact at the restart input.
CAUTION
Restart
If the risk and hazard analysis indicates that a restart is to be implemented in the safety controller, the
restart signal must be applied to a safe input.
The following diagram shows the behavior when an event is triggered via MonIn and subsequent
acknowledgement of the MON function block via the Restart input. At least one of the EDM inputs of the
FB is active.
RESTART
MonIn
MonOut
EDM
FB State
State 1
State 3
State 6
State 1