S_EStopIn input

This state-controlled input evaluates the state of an emergency-stop control device (activated or not activated) connected to the function block.

Data type: SAFEBOOL

Initial value: SAFEFALSE

Connection: Connect this input to an emergency-stop control device 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:

Value	Description
SAFETRUE	The emergency-stop control device is not activated (normal operation). Refer to the hazard message below this table.
SAFEFALSE	The emergency-stop control device is activated (or the wiring to the emergency-stop control device is interrupted or the emergency-stop control device is inoperable). The S_EStopOut output is switched to SAFEFALSE.

You can set a restart inhibit via S_AutoReset in order to control the restart behavior of the function block following a signal change from SAFEFALSE to SAFETRUE at the S_EStopIn input (i.e., after the emergency-stop control device has been deactivated).

If no start-up/restart inhibit has been specified for the function block, the SAFETRUE status at the S_EStopIn input can cause the S_EStopOut output to immediately switch to SAFETRUE.

WARNING
	UNINTENDED START-UP If no start-up/restart inhibit is specified: Be sure that your risk analysis includes an evaluation for the state change at the S_EStopOut output after applying the SAFETRUE status to the S_EStopIn input. Make certain that appropriate procedures and measures (according to applicable sector standards) have been established to help avoid hazardous situations when applying the SAFETRUE status to the S_EStopIn input. Use appropriate safety interlocks where personnel and/or equipment hazards exist. Failure to follow these instructions can result in death, serious injury, or equipment damage.

WARNING

UNINTENDED START-UP

If no start-up/restart inhibit is specified:

Be sure that your risk analysis includes an evaluation for the state change at the S_EStopOut output after applying the SAFETRUE status to the S_EStopIn input.
Make certain that appropriate procedures and measures (according to applicable sector standards) have been established to help avoid hazardous situations when applying the SAFETRUE status to the S_EStopIn input.
Use appropriate safety interlocks where personnel and/or equipment hazards exist.

Failure to follow these instructions can result in death, serious injury, or equipment damage.

Single-channel or two-channel connection of the emergency-stop control device?

Regardless of whether there is a single-channel or two-channel connection between the emergency-stop control device and the Safety Logic Controller, the S_EStopIn input is only connected to one signal of the emergency-stop control device.

When using a two-channel emergency-stop control device, the two-channel signal must be evaluated or monitored as follows:

Either through a suitable upstream function block, e.g., SF_Equivalent function block, if the emergency-stop control device has two N/C contacts.
Or the evaluation of equivalence or antivalence must be performed in the safety-related input device (also see section application example).