{"id":31833,"date":"2023-03-09T11:20:17","date_gmt":"2023-03-09T10:20:17","guid":{"rendered":"https:\/\/www.gt-engineering.it\/?post_type=pubblicazione&#038;p=31833"},"modified":"2026-02-17T12:51:29","modified_gmt":"2026-02-17T11:51:29","slug":"chapter-3","status":"publish","type":"pubblicazione","link":"https:\/\/www.gt-engineering.it\/en\/pubblications\/functional-safety-of-machinery\/chapter-3\/","title":{"rendered":"Chapter 3 &#8211; Main Parameters"},"content":{"rendered":"\n\n    \n        <section\n            data-name=\"Contenuto testuale con immagine\"\n            class=\"bow-gte-testo-media u-spacer-base\"\n            id=\"\"\n        >\n            \n<div class=\"o-text-media px-side-spacer sm:px-side-spacer-sm lg:px-side-spacer-tablet 2xl:px-side-spacer-desktop flex flex-wrap items-start md:block\">\n\n    \n        \n                    <div\n                class=\"h-auto mb-6 md:mb-4 lg:mb-8 xl:mb-9 float-left mr-6 md:mr-4 lg:mr-8 xl:mr-9  overflow-hidden shadow-content-image w-full md:w-1\/3\"\n            >\n                \r\n\r\n    \r\n        \r\n            \r\n                \r\n                    <picture\r\n                        class=\"\"\r\n                                            >\r\n                                                                                                        <source\r\n                                media=\"(max-width: 150px)\"\r\n                                width=\"150\"\r\n                                height=\"150\"\r\n                                srcset=\"https:\/\/www.gt-engineering.it\/wp-content\/uploads\/2023\/03\/Cap-3-150x150.png.webp\"\r\n                                type=\"image\/webp\"\r\n                            \/>\r\n                                                                                <source\r\n                                media=\"(max-width: 300px)\"\r\n                                width=\"300\"\r\n                                height=\"117\"\r\n                                srcset=\"https:\/\/www.gt-engineering.it\/wp-content\/uploads\/2023\/03\/Cap-3-300x117.png.webp\"\r\n                                type=\"image\/webp\"\r\n                            \/>\r\n                                                                                <source\r\n                                media=\"(max-width: 453px)\"\r\n                                width=\"453\"\r\n                                height=\"177\"\r\n                                srcset=\"https:\/\/www.gt-engineering.it\/wp-content\/uploads\/2023\/03\/Cap-3.png.webp\"\r\n                                type=\"image\/webp\"\r\n                            \/>\r\n                                                                                <source\r\n                                media=\"(max-width: 453px)\"\r\n                                width=\"453\"\r\n                                height=\"177\"\r\n                                srcset=\"https:\/\/www.gt-engineering.it\/wp-content\/uploads\/2023\/03\/Cap-3.png.webp\"\r\n                                type=\"image\/webp\"\r\n                            \/>\r\n                                                                            <img\r\n                            class=\"a-image transparent border-image h-auto  w-full\"\r\n                                                        srcset=\"https:\/\/www.gt-engineering.it\/wp-content\/uploads\/2023\/03\/Cap-3.png.webp\"\r\n                                                        title=\"Cap 3\"\r\n                                                        type=\"image\/webp\"\r\n                        \/>\r\n                    <\/picture>\r\n\r\n                \r\n\r\n                    \r\n    \r\n            <\/div>\n        \n                    <div class=\"relative w-full\">\n                \n<div class=\"a-text font-text text-base normal mt-8 first:mt-0 space-y-4\">\n    <p>In <strong>Chapter 3<\/strong>, the <strong>parameters used in both IEC 62061 and ISO 13849-1<\/strong> are described.<\/p>\n<p>IEC 62061 introduced, in the new edition, the important <strong>Failure Rate \u03bbNE<\/strong>, or No Effect Failure, that does not contribute to the SFF of the subsystem.<\/p>\n<p><strong>DC, SFF, MTTFD, CCF<\/strong> are explained in detail. The importance of <strong>HFT<\/strong> (Hardware fault Tolerance) is highlighted and, linked to that, the Route 1H and the Proof Test concepts are presented.<\/p>\n<p>&nbsp;<\/p>\n<p>Here the book paragraphs:<\/p>\n<ul>\n<li><em><a href=\"https:\/\/www.gt-engineering.it\/en\/pubblications\/in-depth-articles-tuttomisure\/p1-reliability-data-for-components-used-in-safety-systems\/\">Failure Rate<\/a> (<strong>\u03bb<\/strong>)<\/em><\/li>\n<li><em>Safe Failure Fraction (<strong>SFF)<\/strong><\/em><\/li>\n<li><em>Diagnostic Coverage (<strong>DC<\/strong>)<\/em><\/li>\n<li><em>Safety Integrity and Architectural Constraints<\/em><\/li>\n<li><em>Mean Time to Failure (<strong>MTTF<\/strong>)<\/em><\/li>\n<li><em>Common Cause Failure (<strong>CCF<\/strong>)<\/em><\/li>\n<li><em>Proof Test<\/em><\/li>\n<li><em>Mission Time and Useful Lifetime<\/em><\/li>\n<\/ul>\n<\/div>            <\/div>\n        \n        \n                <div class=\"clear-both\"><\/div>\n        \n\n    <\/div>\n        <\/section>\n\n    \n","protected":false},"excerpt":{"rendered":"<p>In Chapter 3, the parameters used in both IEC 62061 and ISO 13849-1 are described.<\/p>\n<p>IEC 62061 introduced, in the new edition, the important Failure Rate \u03bbNE, or No Effect Failure, that does not contribute to the SFF of the subsystem.<\/p>\n<p>DC, SFF, MTTFD, CCF are explained in detail. The importance of HFT (Hardware fault Tolerance) is highlighted and, linked to that, the Route 1H and the Proof Test concepts are presented.<\/p>\n","protected":false},"author":2,"featured_media":35572,"parent":30599,"menu_order":3,"template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-31833","pubblicazione","type-pubblicazione","status-publish","has-post-thumbnail","hentry"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.2 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Chapter 3 - Main Parameters - Gt-Engineering<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.gt-engineering.it\/en\/pubblications\/functional-safety-of-machinery\/chapter-3\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Chapter 3 - Main Parameters - Gt-Engineering\" \/>\n<meta property=\"og:description\" content=\"In Chapter 3, the parameters used in both IEC 62061 and ISO 13849-1 are described. 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