I am interested in knowing hot the uncertainty in the L2061XA power meter changes with time. I have found a few documents that mention that there is a "production margin", then there is another uncertainty margin called "Delta Environmental and Drift", then there is another band called "Measurement Uncertainty", and finally a Customer Guard Band (https://www.keysight.com/ca/en/assets/7018-03786/technical-overviews/5991-1732.pdf) . The uncertainty provided in the specifications involves all of these uncertainties. If the power meter is in a temperature and humidity controlled environment, can I expect to have a smaller uncertainty that the specified in the datasheets?. If so, is there any model or approximation that describes how the uncertainty might increase in that environment from the calibration uncertainty to specification uncertainty with time?
Thanks in advance.