S_SafetyActive input

State-controlled input for the status of the zone of operation. This input indicates whether the zone of operation is in the defined safe state. (Monitoring using standstill monitor, for example).

Data type: SAFEBOOL

Initial value: SAFEFALSE

Background (see Exception avoidance): The guard locking on the safety equipment should only be unlocked when the zone of operation is in the defined safe state, for example, by stopping a machine or system.

The safety-related SF_GuardLocking function block itself cannot be used to set the defined safe state of the zone of operation; this must be done separately from the function block. You should then connect the signal that indicates the defined safe state of the zone of operation to the S_SafetyActive input of the safety-related SF_GuardLocking function block.

Only when the zone of operation is in the defined safe state (S_SafetyActive = SAFETRUE) and a request is made to unlock the guard locking on the safety equipment (UnlockRequest = TRUE) does the function block switch the request signal for unlocking the safety equipment to SAFETRUE at its S_UnlockGuard output.

The S_UnlockGuard output controls the coil of the guard locking, i.e., it can lock or unlock the guard locking on the safety equipment.

Connection: Connect this input to an evaluation unit (e.g., standstill monitor) connected to the Safety Logic Controller, either directly or via other safety-related functions/function blocks. Constant SAFETRUE or SAFEFALSE values are not permitted.

If the function block is activated (input Activate = TRUE), the possible values at this input lead to the following function block behavior: