Application Diagnostic of Distributed Control System with Safety PLC

Nowadays almost all commercially available control systems, allow modularity of architecture. It is also similar for control systems based on safety PLC (Programmable Logic Controllers) intended for realization of safety functions. With more possibilities of modularity, we have more choices, how to realize safety functions. Diagnostics is also necessary to achieve the required safety integrity level (SIL) of safety functions. The way how to realize diagnostics for distributed control system can be different than realization of diagnostics for centralized control system. This paper addresses the analysis of the influence of diagnostics in distributed control system on the safety integrity level of realized safety functions.