When designing machine safety control systems, what level of diagnostics is appropriate? This seems to be an issue that causes confusion and inconsistency throughout the industry.
New machine safety standards have now been developed to assist the designer. ISO 13849.1 is a standard that provides a method for the designer to quantify the diagnostics of their safety system, using a measure called Diagnostic Coverage (DC). Each Safety Category will have specific requirements for the DC and the designer will know exactly what level of diagnostics is required for their system.