(SR-52) Practical Reliability & Serviceability Calculations for Complex Systems - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: Not HP Calculators (/forum-7.html) +--- Forum: Not remotely HP Calculators (/forum-9.html) +--- Thread: (SR-52) Practical Reliability & Serviceability Calculations for Complex Systems (/thread-21921.html) |
(SR-52) Practical Reliability & Serviceability Calculations for Complex Systems - SlideRule - 06-20-2024 04:06 PM An excerpt from Computer System Reliability, Wiley, © 1980, pgs. 211-13 & 297-304 Chapter 12 Practical Reliability and Serviceability Calculations for Complex Systems UNITS IN PARALLEL AND IN SERIES Units in Parallel When considering reliability and serviceability of systems with standby systems, the following formula are often quoted: m = mean time between incidents of a single unit d = mean down time per incident s = serviceability of a single unit = … u = unserviceability of a single unit = … M = mtbi dual system = … D = mdti dual system = … S = serviceability of dual system = … Similarly, U = unserviceability of dual system = u² Also for a triplicated system: … … The basic problem with these sort of calculations is that they do not cover the basic case where, say, 2 out of 3 units are required. To cover the calculations, the binomial distribution is more appropriate: … … Appendix 2 gives details of a program for calculating serviceability in units in parallel, for use on a programmable calculator. … … Appendix 2 Serviceability Calculations for Complex Systems Using a Programmable Calculator Chapter 12 showed a method of calculating serviceability of subsystems and systems, including those where standby units are available. The program described provides an easy method of carrying out the calculations and can embrace the weighting factor serviceability scheme. The program listing given is for a Texas SR52 calculator but a flow chart is also included so that the program can be converted to run on other programmable calculators. … BASIC THEORY … WEIGHTING FACTOROPERATION … TIMING … UNITS IN SERIES … FLOWCHART … LISTING … REGISTERS … BEST! SlideRule |