Hazard analysis and risk assessment impact each device

摘要

Sensors play a critical role in safety-instrumented systems (SIS). The lack of guidance that the standards bodies provide is perplexing but reflects the industry's lack of consensus on a benchmark sensor technology. Every design engineer should ask: What type of sensor is best for my SIS? An electromechanical switch is economical and well understood. For an incremental cost, an analog transmitter will give the benefit of a continuous output.