Post updated 2019-07-24. Ed. As promised in previous posts, here is the complete reference list for the series “How to do a 13849-1 analysis”! If you have any additional resources you think readers would find helpful, please add them in the comments.
Read MoreISO 13849-1 Analysis — Part 8: Fault Exclusion
Post updated 2019-07-24. Ed. Fault Consideration & Fault Exclusion ISO 13849-1, Clause 7 [1, 7] discusses the need for fault consideration and fault exclusion. Fault consideration is examining the components and sub-systems used in the safety-related part of the control system (SRP/CS) and making a list of all possible faults. This is a non-trivial exercise!
Read MoreISO 13849-1 Analysis — Part 6: CCF — Common Cause Failures
Post updated 2019-07-24. Ed. What is a “Common Cause Failure”? There are two similar-sounding terms that people often get confused: Common Cause Failure (CCF) and Common Mode Failure. While these two types of failures sound similar, they are different. A Common Cause Failure is a failure in a system where two or more portions of the…
Read More31-Dec-2011 – Are YOU ready?
31-December-2011 marks a key milestone for machine builders marketing their products in the European Union, the EEA and many of the Candidate States. Functional Safety takes a positive step forward with the mandatory application of EN ISO 13849-1 and -2. As of 1-January-2012, the safety-related parts of the control systems on all machinery bearing a…
Read MoreInterlock Architectures — Part 6: Comparing North American and International Systems
Note: This article references now-obsolete versions of standards. Please use the current editions in your work! — DN 2022-08-18 I’ve now written six posts on circuit architectures for the safety-related parts of control systems, including this one. In this post, I will compare the International and North American systems. Comparing the requirements is not intended…
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