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 …
Phase 7: Isolators and Terminal Blocks In this article we discuss the options we have for isolators, converters, barriers, terminal blocks and other components (index of design phases). 7-Isolators, field terminals and prefabricated cables Converters, Isolators and Barriers They are used to convert signal ranges, to electrically isolate two circuits, to duplicate signals, to amplify …
Phase 6: Power Supply and Circuit Breakers In this article we discuss the design of 24 VDC power supply and circuit breakers (index of design phases). 6-Power Supply and Circuit Breakers The design of the power distribution of the control panel is an important aspect that can greatly influence the availability of the plant. Not …
PLC module sizing We want to do some thinking on how to make the PLC module sizing as to the density of the cards, i.e., about what’s the optimal number of channels, and we see that in many cases is more important than it looks like. At first glance all tend to think that the …
Phase 8: Design of Control Cabinet In this article we discuss some options about the internal layout of the control cabinet (index of design phases). 8-Design of the control cabinet There are many factors that impact the internal design of a control cabinet and, therefore the mounting space required. There is no clear rule …
