Library Free [exclusive]: Beckhoff Sistema

| Component | Cost Status | Condition | | :--- | :--- | :--- | | Tc3_Sistema Library (source) | (royalty-free) | Requires valid TwinCAT 3 development environment. | | TwinCAT Runtime on target PC/PLC | Paid | Minimum level TC1220 (PLC standard) for non-safety logic. | | TwinCAT Safety Runtime | Paid | Requires TC1230 (Safety PLC) license on the target. | | Safety I/O Terminals (e.g., EL1904, EL2904) | Paid | Hardware with integrated safety CPU. |

// Input from EL1904 (channel 1 - E-Stop button, dual-channel) VAR_INPUT Safe_EStop_ChA : SAFEBOOL; // Channel A of emergency stop Safe_EStop_ChB : SAFEBOOL; // Channel B Reset_Button : SAFEBOOL; // Manual reset (non-safe, but used in safety FB) END_VAR