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[email protected] gfretwell@aol.com is offline
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Default Thermometers: What's the Problem with Accuracy?

On Mon, 5 Feb 2018 20:45:50 -0700, rbowman wrote:

On 02/05/2018 11:11 AM, (PeteCresswell) wrote:
Per dpb:
The problem with inexpensive bulb thermometers is that the capillary
dimension has to be exceedingly precise in order to control both the
linearity and scaling and doing that drives the price up


What type would you say is the least prone to inaccuracy?

Bi-metallic spring?

Digital?

I have played around with digital sensors and a Raspberry PI and the accuracy
was pretty bad.... but maybe that's just el-cheapo sensors and/or my
programming approach...


Thermistor or RTD? A good RTD is fairly linear but thermistors need a
lot of processing.

https://en.wikipedia.org/wiki/Steinh...3Hart_equation

Warning: funny math symbols ahead...


There are also linear solutions using the LM134 and similar.