In the scenario where you have a calculated temperature for the 1C reading but encounter an EUUU message (as opposed to EAAA) situation for the 2C reading, several factors come into play.
These include excessive signal reduction due to factors such as emissivity, object size and/or sight path obstruction (including transmission losses from a viewport window). Additionally, attempting to measure a temperature close to the sensor’s minimum measurable value exacerbates the issue.
To achieve reliable measurements at the lower end of the sensor’s range, it’s essential to work with an object that has an emissivity value (at the nominal measured temperature) of at least 0.45 (equivalent to 55% attenuation).
For instance, consider an E1RH sensor, which can reliably measure down to 1100°C with 80% attenuation (or if the combination of emissivity and window transmissivity as a factor is 0.2):
Similarly, an E1RL sensor provides its lowest reading of 675°C with 80% attenuation:
With the same condition as E2RL sensor will start at 360°C.
