[time-nuts] What do people use for measuring temperature?

[Bruce Griffiths]

If one does a ratiometric measurement comparing the voltage drop across the RTD with the voltage drop across a stable low Tc resistor connected in series with the RTD the excitation source only needs to be quiet with good short term stability.

Bruce

> On 29 September 2020 at 07:48 "John Moran, Scawby Design" <john at scawbydesign.co.uk> wrote:
> 
> 
> Thanks for going easy on me Bob ... a case of more haste, less speed! I focussed on low long-term drift specs without realising I had turned up a voltage reference, sorry.
> 
> However, I have found some YSI glass encased thermistors that have long-term drift specs of <10mK at 25C and 75C over a period of 100 months. They are in the YSI 46000 series - data sheet attached.
> 
> http://www.farnell.com/datasheets/169207.pdf
> 
> There is an interesting paper by NIST on achieving the International Temperature scale - link attached (it is 196 pages and 10MB) that seems to indicate platinum sensors are the most stable at less than 1mK and, of course, to be able to measure these resistors accurately, you need an equally low-drift voltage/current source. :-)
> 
> https://nvlpubs.nist.gov/nistpubs/Legacy/TN/nbstechnicalnote1265.pdf
> 
> This reference appeared from an EEVblog where I think some Volt-nuts were discussing temperature. One of them confirmed that the most economical way was to have a group of lower-cost sensors and characterise them.
> 
> https://www.eevblog.com/forum/metrology/long-term-stability-of-temperature-sensors/
> 
> John 
> 
> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.