Sneak Circuit Analysis: Lessons Learned from Near Miss Event
Centre of Competence for Mass Transit, AME, Bombardier Transportation, Kingston, Canada.
Received on September 06, 2016
Accepted on October 24, 2016
Sneak Circuit Analysis is intended for critical applications which are essential to mission success and safety. A sneak condition will occur when a designed circuit inhibits a wanted function or results in an unwanted function. Sneak conditions originate from one of the four following scenarios: a sneak path resulting in a flow of electrical current along an unexpected route; a sneak timing that may cause the activation of some desired/designed functionality at an unexpected time; a sneak indication in monitoring functions that may result in an ambiguous or false display of system operating conditions; and lastly, a sneak label which may induce operator error due to inappropriate instruction. This paper introduces a near miss event that occurred in the Sao Paulo monorail which was caused by a sneak time condition. Root cause analysis and design modifications are also discussed in the paper.
Keywords- Sneak circuit analysis (SCA), Sneak timing, Door enable, Door inhibit, Propulsion enable.
Li, J. (2017). Sneak Circuit Analysis: Lessons Learned from Near Miss Event. International Journal of Mathematical, Engineering and Management Sciences, 2(1), 30-36. https://dx.doi.org/10.33889/IJMEMS.2017.2.1-003.
Conflict of Interest
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