Mean Time to System Failure and Availability Modeling of a Repairable non Identical Three Unit Warm Standby Redundant System

Most of the studies on reliability characteristics of redundant systems deal with cold standby systems only. Little attention is paid on 2-out-of-3 warm standby system involving three types of failures. In this study models for mean time to system failure and availability have been developed to study the effect of failure rate on some measures of system effectiveness. Using Chapman Kolmogorov’s forward equations methods, explicit expressions for measures of system effectiveness like mean time to system failure (MTSF) and availability have been obtained. Graphs were plotted to see the behavior of MTSF and availability of system. Also a special case like linear consecutive 2-out-of-3 system is considered to see the effect of failure rate on system design. Results show that three units warm standby is more effective that linear consecutive 2-out-of-3 system.