Prediction methods for equipment reliability evaluation

The prediction of electronic equipment reliability is especially important where hazardous processes and risks to plant and personnel are involved and where low values of fail-dangerous rates for the equipment are consequently required. Three methods of failure rate prediction are discussed: the total component count, the functional block analysis and the failure modes and effects analysis. The effect of application, temperature and loading upon electronic failure rates are discussed and this is followed by a consideration of the possible accuracy with which failure rates can be predicted. It is demonstrated that, with care, most predictions should agree with field observations to within a factor of 2