5. Conclusions

There are two types of control lines for discrete event systems: those with discrete inputs and outputs, and those with analog inputs and discrete output. Twelve logics that were analyzed and converted into Petri network models.

For dynamic behavior of the PN model proposed, constraints and equations for marking places and firing transitions are indicated to consider the problems of mark accumulation and the restarting condition of the structure PN.

LDPN to discrete event systems allow to model control lines used in LD language, and consequently, control algorithms development in LD, supporting that these are safe and reliable.

Each PN model is independent and can be interconnected in function of the control logic, as well as, the number of PN model that is needed can be integrated.
