1 / 11

Dependability Theory and Methods Part 4: Fault-tree analysis

Dependability Theory and Methods Part 4: Fault-tree analysis. Andrea Bobbio Dipartimento di Informatica Universit à del Piemonte Orientale, “ A. Avogadro ” 15100 Alessandria (Italy) bobbio@unipmn.it - http://www.mfn.unipmn.it/~bobbio. Bertinoro, March 10-14, 2003.

ursa-deleon
Download Presentation

Dependability Theory and Methods Part 4: Fault-tree analysis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Dependability Theory and MethodsPart 4: Fault-tree analysis • Andrea Bobbio • Dipartimento di Informatica • Università del Piemonte Orientale, “A. Avogadro” • 15100 Alessandria (Italy) • bobbio@unipmn.it - http://www.mfn.unipmn.it/~bobbio Bertinoro, March 10-14, 2003 Bertinoro, March 10-14, 2003

  2. Elements of logic algebra

  3. Elements of logic algebra

  4. Elements of logic algebra

  5. Logic algebra and Venn diagrams

  6. Fundamental assumptions for FTA • Events are binary events (working/non-working); • Events are statistically independent; • Relationships between events and causes are represented by logical AND and OR (Boolean) gates; • The root of the FT is the catastrophic undesired event called the Top Event (TE).

  7. Case study: a PLC architecture Bertinoro, March 10-14, 2003

  8. Case study: a PLC architecture The considered failure rates for the elementaryblocks are reported in the Table. Bertinoro, March 10-14, 2003

  9. PLCarchitecture: FTA Bertinoro, March 10-14, 2003

  10. Safety and dependability measures • Safety assessment of the control systemaccording to IEC 61508 (Functional safety ofelectrical/electronic/ programmable electronic safety-relatedsystems) • SIL requirements (IEC 61508); • Unreliability versus time; • Safe Mission Time (SMT); • Mean Time To Failure; • Critical failure path (mcs). Bertinoro, March 10-14, 2003

  11. FT Critical cuts The FT has 59 MCS, one oforder 1 (the voter) and theremaining 58 of order 2. Bertinoro, March 10-14, 2003

More Related