The Random Failure Statistics and Replacement Schedules of Remote Devices for Load Management

The flat portion of the classical bath-tub curve is still generally accepted as a basis for random failure statistics of some type of components or equipments exposed to environmental stresses. To maintain a high degree of availability of remote devices for load management, scheduled replacements of failed units are necessary. A mathematical tool is developed in this paper which can be used to assess the impact of MTBF of remote devices for load management on costs associated with initial installation, operational costs with scheduled replacements and the cost of reliability. Some examples using certain assumed cost figures serve to illustrate the use of the derived formulas.