Machinery Safety 101

Inconsistencies in ISO 13849 – 1:2006

This entry is part 7 of 8 in the series Cir­cuit Archi­tec­tures Explored

I’ve writ­ten quite a bit recently on the top­ic of cir­cuit archi­tec­tures under ISO 13849 – 1, and one of my read­ers noticed an incon­sist­ency between the text of the stand­ard and Fig­ure 5,… 

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Interlock Architectures Pt. 6 – Comparing North American and International Systems

industrial Control Console
This entry is part 6 of 8 in the series Cir­cuit Archi­tec­tures Explored

I’ve now writ­ten six posts, includ­ing this one, on the top­ic of cir­cuit archi­tec­tures for the safety-related parts of con­trol sys­tems. In this post, we’ll com­pare the Inter­na­tion­al and North… 

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Interlock Architectures – Pt. 4: Category 3 – Control Reliable

Category 3 Architecture Logic Block Diagram
This entry is part 4 of 8 in the series Cir­cuit Archi­tec­tures Explored

This post was updated on 2020-03-28. Cat­egory 3 sys­tem archi­tec­ture is the first cat­egory that could be con­sidered to have sim­il­ar­ity to “Con­trol Reli­able” cir­cuits or sys­tems as was defined in… 

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Missing MTTFd data

Deal­ing with the huge inform­a­tion void that exists while try­ing to com­plete reas­on­able con­trol reli­ab­il­ity assess­ments is a major chal­lenge for every engin­eer or tech­no­lo­gist tasked with this activ­ity. Here are a few thoughts on what to do now, and where things may be going…

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