A New experimental procedure for estimating and predicting of a standard platinum resistance thermometer (SPRT) lifetime in a case study

The platinum resistance thermometers (PRTs) are very important devices in temperature measurement at industry. These applicable devices need to be calibrated periodically to be giving reliable measurements. SPRT is a device that use for PRT calibration. SPRT operation must be completely accurate and reliable to be useful for PRT calibration. This paper is a result of a long time research to estimate the lifetime of a SPRT based of periodic investigation. In fact, a SPRT must be considered as a deteriorating element which has an unknown lifetime, so we made periodic measurement from SPRT readings and extract normal error of its data in every instance. Increasing errors showed us that its lifetime can be estimated by exponential distribution. So a curve fitting is done to fit the measured points to this distribution and finally predict its lifetime.