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• Activate input

Activate input

State-controlled input for activating the function block.

Data type: BOOL
Initial value: FALSE

Connection: With TRUE constant or TRUE/FALSE input signal.

Connecting the Activate input to an input signal makes it possible to switch off specific safety-related functions in a targeted manner (e.g., individual areas of machines and systems with a modular construction).

The function block is deactivated when Activate = FALSE. Deactivated function blocks switch their outputs to the defined safe state. S_EStopOut = SAFEFALSE and Error = FALSE signals that no error has been detected.

Further Info Application examples and information on how to carry out individual deactivation, group deactivation or how to set up modular safety-related equipment using function block activation can be found in "Activating function blocks ‣ Activating Function Blocks (Activate) ×‣ Activating Function Blocks (Activate) ×".

Value	Description
TRUE	The function block is activated, the inputs are evaluated, and the outputs switched accordingly. Note S_StartReset = SAFEFALSE specifies a start-up inhibit which becomes active once the function block has been activated and after the Safety PLC has been started up. S_AutoReset = SAFEFALSE is used to specify a restart inhibit which is active after withdrawing the request for the safety-related function. Both inhibits are removed by a FALSE > TRUE edge at the Reset input. Once the active inhibits have been removed, the status at the S_EStopOut output can immediately switch from SAFEFALSE to SAFETRUE (depending on the other input signals). Refer to the warning below this table.
FALSE	The function block is not activated. The S_EStopOut output is switched to SAFEFALSE.

WARNING

Unintended start-up Be sure that your risk analysis includes an evaluation for the state change at the S_EStopOut output after activating the safety-related function block or after removing the start-up and/or restart inhibit. Make certain that suitable organizational measures (according to applicable sector standards) have been taken to help avoid hazardous situations when activating the safety-related function block or when removing the start-up and/or restart inhibit. Use appropriate safety interlocks where personnel and/or equipment hazards exist.