I'm looking for a way to measure temperatures in range of 40 to -200 °C (100 to −320 °F). The usual solution DS18B20 works only down to -55 °C (-67 °F).
Any ideas?
p.s. Precision of 2 °C would be good enough.
I'm looking for a way to measure temperatures in range of 40 to -200 °C (100 to −320 °F). The usual solution DS18B20 works only down to -55 °C (-67 °F).
Any ideas?
p.s. Precision of 2 °C would be good enough.
You probably want a K-type thermocouple (the most common type).
They have a range of around -200°C to +1350°C (depending on probe).
Alternatively a Resistive Temperature Device (RTD) can be used, since these have a typical range of around -240°C to 650°C with higher accuracy.
This might be of help to you: http://digital.ni.com/public.nsf/allkb/C50FA55B3B2F85D9862572D00083350E
I did a search on "cryogenic temperature sensors" and found these from Lake Shore Cyrotronics – the price is shocking. It appears that you can use silicon diodes as cryogenic temperature sensors, so you might be able to use less expensive parts if you don't need a ton of accuracy.