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• Implementation of safety requirements from applicable standards

Implementation of safety requirements from applicable standards

The safety-related function block has been developed according to the safety requirements (from applicable standards) listed in this section. All other requirements from these standards must be observed when implementing the safety-related function.

This section describes either how the function block meets the requirements of the standards or what measures need to be taken to meet the requirements of the standards.

Standards	Context/Requirement	Implementation
EN  ISO 13851	Use of both hands (simultaneous actuation)	The safety-related function block only switches its enable signal to SAFETRUE if the signals at S_Button1 and S_Button2 switch from SAFEFALSE to SAFETRUE synchronously or within 500 ms, after being not actuated before.
	Relationship between input signals and output signals/Cessation of the output signal	The enable signal of the safety-related function block is switched from SAFETRUE to SAFEFALSE if S_Button1 and/or S_Button2 switch to SAFEFALSE.
	Re-initiation of the output signal	When the states at S_Button1 and S_Button2 change from SAFEFALSE to SAFETRUE, the safety-related function block only switches its enable signal to SAFETRUE again if both S_Button1 and S_Button2 initially show the SAFEFALSE state after the enable signal has been switched off (enable signal = SAFEFALSE).
	Category 3 application	Implementation of the two-hand control device must comply with the requirements of EN ISO 13849-1 for safety category 3.
EN ISO 12100-2	Start-up after failure of supply voltage/spontaneous restart	If S_Button1 and/or S_Button2 are showing the SAFETRUE state during function block activation, the safety-related function block detects this as an error. The enable signal cannot be switched to SAFETRUE while this error state is present. To reset this error state, both S_Button1 and S_Button2 must show the SAFEFALSE state.
EN ISO 13849-1	Category 3	You are responsible for implementing the requirements of category 3 for the two-hand control device. A single-channel design for the buttons is only permitted if the safety chain (loop) for the connected buttons of the two-hand control device meets the requirements of EN ISO 13849-1 up to category 3 in terms of single-channel applications. With this in mind, the following components of the safety chain need to be considered in each case: Sicherheitssteuerung used for the two-hand safety-related function, including programming (cross-circuit detection). the connection and cabling between the Sicherheitssteuerung and the button of the two-hand operator panel, and the complete two-hand operator panel. Please refer to the user documentation specific to the devices used in the safety chain for details of other measures which need to be taken. Hinweis Cross-circuit monitoring is not performed by the function block. It is your responsibility to implement this monitoring function outside of this function block in the safety-related control system. For example, a safety-related SF_Antivalent function block must be connected upstream for the purpose of evaluating signals if two-channel buttons with one N/C contact and one N/O contact are being used.