S_EnableSwitchOut output

Output signal of the function block (enable signal).

Data type: SAFEBOOL

The enable signal depends on the switching stage of the enable switch, the restart inhibit (S_AutoReset) that has been set, the reported operating mode (S_SafetyActive), and any active error message.

Hinweis
As the enable signal is present at the S_EnableSwitchOut output, this output is also referred to as the enable output.

Connection: Connect the S_EnableSwitchOut output to an output terminal of your application, either directly or via other safety-related functions/function blocks.

The enable signal may only control the process directly if this does not adversely affect the safety-related function.

WARNUNG

Unintended machine operation

Verify that the enable signal only controls the process directly if this does not adversely affect the safety-related function.

Validate the overall safety-related function, including the start-up behavior of the process, and thoroughly test the application.

Only control the subsequent process with this enable signal if a selected operating mode (limitation of the speed or range of motion) is active. You can use the S_SafetyActive input of the function block to ensure that the operating mode is active. To do this, connect the input to the safe SF_ModeSelector function block in such a way that you can evaluate a feedback signal as a condition for an active operating mode.

WARNUNG

Non-conformance to safety function requirements

Verify that the S_SafetyActive input of the function block is correctly used to evaluate the operating mode of the subsequent process.

Verify that the enable signal only controls the subsequent process if the required operating mode is signaled at the S_SafetyActive input.

Value Description

SAFETRUE The process to be controlled (e.g., removal of safeguarding) is enabled. The enable switch is actuated correctly.
The following conditions must be met:

The function block has been activated (input Activate = TRUE)

and the operating mode is active (S_SafetyActive = SAFETRUE)

and the enable switch has been actuated correctly (switching stage 2)

and no restart inhibit is active

and the function block has not detected an error.

SAFEFALSE The process to be controlled (e.g., removal of safeguarding) is not enabled.
This may be due to one of the following reasons:

The function block is not active (input Activate = FALSE)

or the operating mode is not active (S_SafetyActive = SAFEFALSE)

or the combination of the signal levels at the inputs indicates to the function block that the enable switch has not been actuated, or has not been actuated correctly (switching stage 1 or 3)

or a restart inhibit is active

or the function block has detected an error.

Value	Description
SAFETRUE	The process to be controlled (e.g., removal of safeguarding) is enabled. The enable switch is actuated correctly. The following conditions must be met: The function block has been activated (input Activate = TRUE) and the operating mode is active (S_SafetyActive = SAFETRUE) and the enable switch has been actuated correctly (switching stage 2) and no restart inhibit is active and the function block has not detected an error.
SAFEFALSE	The process to be controlled (e.g., removal of safeguarding) is not enabled. This may be due to one of the following reasons: The function block is not active (input Activate = FALSE) or the operating mode is not active (S_SafetyActive = SAFEFALSE) or the combination of the signal levels at the inputs indicates to the function block that the enable switch has not been actuated, or has not been actuated correctly (switching stage 1 or 3) or a restart inhibit is active or the function block has detected an error.

A SAFETRUE signal at the S_EnableSwitchOut output alone must not be used to initiate the start of the machine. An additional intentional start command, which is independent of the enable switch(es), is required for this. Every person inside the zone of operation must carry an enable switch, which can be used to help prevent a machine state change.

WARNUNG

Non-conformance to safety function requirements

Verify that an additional intentional start command, which is independent of the enable switch (i.e, independent of a SAFETRUE signal at the S_EnableSwitchOut output), is used to start the operation of the machine.

Ensure that every person inside the zone of operation carries an enable switch.

Precise details of the behavior of the S_EnableSwitchOut output in relation to the restart inhibit are given in the following table:

Formal parameter Value Action Restart inhibit Reset Enable output

S_AutoReset SAFETRUE If an invalid switch position leads to an error, after removal of that error (release > switching stage 1) the restart inhibit is not active No action is required at Reset, ... - to exit the current error state.
- to exit the restart inhibit.
To switch the S_EnableSwitchOut output to SAFETRUE, switch position 2 is then required.

SAFEFALSE active Reset must be switched from FALSE to TRUE, ...

Formal parameter	Value	Action	Restart inhibit	Reset	Enable output
S_AutoReset	SAFETRUE	If an invalid switch position leads to an error, after removal of that error (release > switching stage 1) the restart inhibit is	not active	No action is required at Reset, ...	- to exit the current error state. - to exit the restart inhibit. To switch the S_EnableSwitchOut output to SAFETRUE, switch position 2 is then required.
SAFEFALSE	active	Reset must be switched from FALSE to TRUE, ...

Hinweis
Additional measures, e.g., an additional function stop, can be taken to reduce the risk of an unintended start-up.