If you are interested in functional safety, and I know many readers are based on the statistics I see for my other functional safety-related posts, I think you will be interested in this.…
Read MoreTrapped Key Interlocking

Many machine designers think of interlocks as exclusively electrical devices; a switch is attached to a movable mechanical guard, and the switch is connected to the control system. Trapped Key Interlocking is…
Read MoreQ & A: Category 2 and Testing Intervals

During the Free Safety Talks that we did with Schmersal Canada and Franklin Empire, we had a “hot question” come up regarding Category 2 architecture and the testing interval requirement. The…
Read MoreFive reasons you should attend our Free Safety Talks

Reason #1 – Free Safety Talks You can’t argue with Free Stuff! Last week we partnered with Schmersal Canada and Franklin Empire to put on three days of Free Safety…
Read MoreSafe Drive Control including Safe Torque Off (STO)

Ed. Note: This article was revised 25-Jul-17 to include information on safe standstill. Safe Drive Control including STO Motor drives are everywhere. From DC variable speed drives and indexing drives,…
Read MoreHow to do a 13849 – 1 analysis: Complete Reference List
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…
Read MoreISO 13849 – 1 Analysis — Part 7: Safety-Related Software

Post updated 2019-07-24. Ed. Safety-Related Software Up to this point, I have been discussing the basic processes used for the design of safety-related parts of control systems. The underlying assumption is…
Read MoreISO 13849 – 1 Analysis — Part 3: Architectural Category Selection
Post updated 2019-07-24. Ed. At this point, you have completed the risk assessment, assigned required Performance Levels to each safety function, and developed the Safety Requirement Specification for each safety…
Read MoreISO 13849 – 1 Analysis — Part 2: Safety Requirement Specification
This article was updated 2019-07-24. Ed. Developing the Safety Requirement Specification The Safety Requirement Specification sounds pretty heavy, but actually, it is just a big name for a way to organize the…
Read MoreISO 13849 – 1 Analysis — Part 1: Start with Risk Assessment
This post was updated 2019-07-24 I often get questions from clients about how to get started on Functional Safety using ISO 13849. This article is the first in a series that will…
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