Method for evaluating life cycle of an electric instrument control system

PURPOSE: A method for evaluating lifespan of an electric instrument control system is provided to accurately the residual lifespan of the control system by reflecting the number of failure of the control system on workplace conditions. CONSTITUTION: The number of failure in a control system is detected(S1). The number of failure is a value between an initial time and a lifespan of the control system. A weighted value according to workplace conditions is set(S2). Reduced lifespan is evaluated in reflection the weighted value. The residual lifespan of the control system is evaluated(S3). The residual lifespan is inverse proportion to the number of failure of the control system.