Reliability Block Diagrams (RBDs) helper for review.


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More "pictures instead of words"

I couldn't find a) all the RBDs on one page, and b) any RBDs that didn't have R1=R2=R2 examples. So, I broke these down so they show how to work these if R1 and R2 are NOT equal. (Not a problem for series, but for parallel with R1 <> R2, the squared, cubed etc. formula doesn't work).

I appreciate the review, suggestions, etc.




  • RBD v2.pdf
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This is correct. I would add a definition of R and emphasize that the reliability used in the RBD must be at the same point in time. That is, you cannot multiply R(12 months) = 0.95 by R(24 months) = 0.92. Further, the calculated answer also only applies to that same time period.

This is usually ignored in virtually all classes and materials, and is not even stated as an assumption.
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