PURPOSE: To devise a provision to prevent the failure of an electronic component for improving reliability by using the acceleration factor of component life, input history data and working hours, and predicting the component life by means of a microprocessor.
CONSTITUTION: The displacement by differential pressure pressed to a moving electrode is converted 11 from capacity to duty by way of a differential pressure sensor 10. A temperature sensor 22, a humidity sensor 23 and a vibration sensor 24 convert environmental variables to electric signals and they are A/D converted 26 together with the static pressure signal from a static pressure sensor 9 to be input to a processor 12. In a memory 14, input history, working hours, etc., of each sensor 9, 10, 22, 23 and 24 are stored. In a memory 15, output correction factor for pressure and temperature and the acceleration factor of component life determined by performing acceleration tests in advance are stored. Under the control of processor 12, an alarm is generated when a specific time prior to the life time estimated from the working hours is reached.
SAITO YOJI
HORIO YASUAKI
