The GRAFCET I/O component is used to link the GRAFCET variables with the electrical part of a circuit. You can enter eight GRAFCET input variables and eight GRAFCET output variables into the GRAFCET I/O component. The actions' variables serve as outputs. The inputs can be the allocations and conditions of actions and transitions.

If a potential is created as the input of the GRAFCET I/O component, the corresponding variable is set to 1. If an output variable has a value other than 0, a potential of 24V is created at the corresponding output of the GRAFCET I/O component.