The importance of common cause failures When designing a control system, we should paid special attention to common cause failures, that is, to the factors that may cause the simultaneous failure of several components or redundant channels. It is an even more important aspect in the case of safety instrumented systems (SIS) and is considered …
BMS Safety PLC Let’s see an example of I/Os distribution in the case of a safety PLC for a Boiler Protection and Burner Management System for a Heat Recovery Steam Generator with post-combustion. The boiler has 8 burner ramps as shown in the image. It is advisable to use a safety PLC and verify the …
Input/Output Architecture in the control system We will give an overview of most common input/output architectures in a control system, depending on whether the priority is “Safety” or “Availability“. 1-Architectures of Inputs The following image shows the most common configurations. The letter “D” in yellow stands for “Diagnosis” and usually is associated with the Safety …
Basic concepts of redundant architecture of PLC In this article we will go over the most usual options to configure a redundant architecture. We will focus on some of the most commons and we will have occasion to study them more deeply in a future post. Depending on the application we will have to determine …
