Additional signal sequence diagrams

Temporary intermediate states are not illustrated in the signal sequence diagrams. Only typical input signal combinations are illustrated in these diagrams. Other signal combinations are possible.

The most significant areas within the signal sequence diagrams are highlighted in color.

Note
This documentation refers to the monitored electro-sensitive protective equipment as ESPE for short.

Further Info
Please refer also to the diagram found in the overview for this function block.

Monitoring a light grid: No start-up inhibit, but restart inhibit

S_StartReset = SAFETRUE: No start-up inhibit after the Safety PLC has been started up/the function block has been activated

S_AutoReset = SAFEFALSE: Active restart inhibit after the light grid that was previously interrupted is no longer interrupted (SAFETRUE signal has returned at S_ESPE_In input)

0 The function block is not yet activated (Activate = FALSE).
As a result, all outputs are FALSE or SAFEFALSE.
The light grid is not interrupted (S_ESPE_In = SAFETRUE).

1 Function block activated by Activate = TRUE. The S_ESPE_Out output becomes SAFETRUE immediately, as no start-up inhibit after start-up/function block activation has been specified with S_StartReset.

2 Request for the safety-related function. The light grid is interrupted. The S_ESPE_Out output becomes SAFEFALSE.

3 The light grid is no longer interrupted and the S_ESPE_Out output remains SAFEFALSE at first, as the restart inhibit has been specified by S_AutoReset once the SAFETRUE signal has returned at the S_ESPE_In input.

4 Positive signal edge at the Reset input resets the restart inhibit, followed by normal operation. The S_ESPE_Out output becomes SAFETRUE.

5 Request for the safety-related function. The light grid is interrupted. The S_ESPE_Out output becomes SAFEFALSE.

6 The light grid is no longer interrupted and the S_ESPE_Out output remains SAFEFALSE at first, as the restart inhibit has been specified by S_AutoReset once the SAFETRUE signal has returned at the S_ESPE_In input.

7 Positive signal edge at the Reset input resets the restart inhibit, followed by normal operation. The S_ESPE_Out output becomes SAFETRUE.

Evaluating a light curtain: Start-up inhibit, no restart inhibit

S_StartReset = SAFEFALSE: Active start-up inhibit after the Safety PLC has been started up

S_AutoReset = SAFETRUE: No restart inhibit once the light curtain that was previously interrupted is no longer interrupted

0 The function block is not yet activated (Activate = FALSE).
As a result, all outputs are FALSE or SAFEFALSE.
The light curtain is already interrupted (S_ESPE_In = SAFEFALSE).

1 After the function block has been activated by Activate = TRUE, the start-up inhibit is active at first.

2 The light curtain that was previously interrupted is no longer interrupted (object removed from zone of operation). The S_ESPE_Out output remains SAFEFALSE at first, as S_StartReset = SAFEFALSE has been used to specify a start-up inhibit after the Safety PLC has been started up and after the function block has been activated.

3 Positive signal edge at the Reset input resets the start-up inhibit, followed by normal operation. The S_ESPE_Out output becomes SAFETRUE.

4 Request for the safety-related function. The light curtain is interrupted, the S_ESPE_Out output becomes SAFEFALSE.

5 The light curtain is no longer interrupted. The S_ESPE_Out output becomes SAFETRUE immediately, as no restart inhibit was specified with S_AutoReset = SAFETRUE after the return of the SAFETRUE signal at the S_ESPE_In input.

6 Request for the safety-related function. The light curtain is interrupted, the S_ESPE_Out output becomes SAFEFALSE.

7 The light curtain is no longer interrupted. The S_ESPE_Out output becomes SAFETRUE immediately, as no restart inhibit was specified with S_AutoReset = SAFETRUE after the return of the SAFETRUE signal at the S_ESPE_In input.

0	The function block is not yet activated (Activate = FALSE). As a result, all outputs are FALSE or SAFEFALSE. The light grid is not interrupted (S_ESPE_In = SAFETRUE).
1	Function block activated by Activate = TRUE. The S_ESPE_Out output becomes SAFETRUE immediately, as no start-up inhibit after start-up/function block activation has been specified with S_StartReset.
2	Request for the safety-related function. The light grid is interrupted. The S_ESPE_Out output becomes SAFEFALSE.
3	The light grid is no longer interrupted and the S_ESPE_Out output remains SAFEFALSE at first, as the restart inhibit has been specified by S_AutoReset once the SAFETRUE signal has returned at the S_ESPE_In input.
4	Positive signal edge at the Reset input resets the restart inhibit, followed by normal operation. The S_ESPE_Out output becomes SAFETRUE.
5	Request for the safety-related function. The light grid is interrupted. The S_ESPE_Out output becomes SAFEFALSE.
6	The light grid is no longer interrupted and the S_ESPE_Out output remains SAFEFALSE at first, as the restart inhibit has been specified by S_AutoReset once the SAFETRUE signal has returned at the S_ESPE_In input.
7	Positive signal edge at the Reset input resets the restart inhibit, followed by normal operation. The S_ESPE_Out output becomes SAFETRUE.

0	The function block is not yet activated (Activate = FALSE). As a result, all outputs are FALSE or SAFEFALSE. The light curtain is already interrupted (S_ESPE_In = SAFEFALSE).
1	After the function block has been activated by Activate = TRUE, the start-up inhibit is active at first.
2	The light curtain that was previously interrupted is no longer interrupted (object removed from zone of operation). The S_ESPE_Out output remains SAFEFALSE at first, as S_StartReset = SAFEFALSE has been used to specify a start-up inhibit after the Safety PLC has been started up and after the function block has been activated.
3	Positive signal edge at the Reset input resets the start-up inhibit, followed by normal operation. The S_ESPE_Out output becomes SAFETRUE.
4	Request for the safety-related function. The light curtain is interrupted, the S_ESPE_Out output becomes SAFEFALSE.
5	The light curtain is no longer interrupted. The S_ESPE_Out output becomes SAFETRUE immediately, as no restart inhibit was specified with S_AutoReset = SAFETRUE after the return of the SAFETRUE signal at the S_ESPE_In input.
6	Request for the safety-related function. The light curtain is interrupted, the S_ESPE_Out output becomes SAFEFALSE.
7	The light curtain is no longer interrupted. The S_ESPE_Out output becomes SAFETRUE immediately, as no restart inhibit was specified with S_AutoReset = SAFETRUE after the return of the SAFETRUE signal at the S_ESPE_In input.