As suggested in a prevous thread, I am planning to use the DT-670-CU-70L sensors to monitor the stability of a large structure around 80K. Requirements include both high accuracy (then calibrated sensors) and the stability for operation over many years (few cycles to 80K at 1-year interval over many years). Indeed, these sensors are located in an area with difficoult access and cannot be dismounted for periodic re-calibration. I am asking answer and advice for the following questions:
1. How stable is the sensor calibration with time? Are any drift in calibration reported? Are any literature available on DT-670 sensors calibration stability?
2. 40 mK long-term stability is reported as the result of 200 thermal shocks. It is meant as data dispersion. My question is: are these data distributed simmetrically around the mean or is there any effect of calibration drift with time (asimmetry in distribution)? This last information will greatly help me in understating the stability of calibration.