tempcontroller:sensor
Differences
This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision Next revision | Previous revision | ||
|
tempcontroller:sensor [2010/03/03 22:51] ladyada |
tempcontroller:sensor [2016/01/28 18:05] (current) |
||
|---|---|---|---|
| Line 42: | Line 42: | ||
| ==== Accuracy & Precision ==== | ==== Accuracy & Precision ==== | ||
| - | K type thermocouples have accuracy of 2°C (±1°C) and precision of about 0.5°C (±0.2°C) | + | K type thermocouples have accuracy of 2.2°C (±1.1°C) or 0.75% (whichever is higher) and precision of about 0.5°C (±0.2°C) |
| Because the voltages across the wires are so small (in the uV range!) the precision probably has more to do with your amplifier and any hash (noise) pickup than with the thermocouple itself. | Because the voltages across the wires are so small (in the uV range!) the precision probably has more to do with your amplifier and any hash (noise) pickup than with the thermocouple itself. | ||
| - | I find it confusing that products like the [[http://www.thermoworks.com/products/thermapen/splashproof_thermapen.html|Thermapen]] have 0.1°F precision displays when the product accuracy & precision is almost certainly much lower (that is, less precise). If anyone understands this, would appreciate an explanation. | + | > I find it confusing that products like the [[http://www.thermoworks.com/products/thermapen/splashproof_thermapen.html|Thermapen]] have 0.1°F precision displays when the product accuracy & precision is almost certainly much lower (that is, less precise). If anyone understands this, would appreciate an explanation. |
| ==== Range ==== | ==== Range ==== | ||
| Line 54: | Line 54: | ||
| ==== Amplifiers & Interfaces ==== | ==== Amplifiers & Interfaces ==== | ||
| - | The [[http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3149|MAX6675]] has a resolution/precision of 0.25°C | + | The [[http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3149|MAX6675]] has a resolution of 0.25°C. |
| + | |||
| + | However, the error (inaccuracy?) is about +-8 LSB. 2*8*0.25°C = 4°C (±2°C) that should be added on TOP of the ±1.1°C / 0.75% sensor probe inaccuracy | ||
| ==== Pricing ==== | ==== Pricing ==== | ||
/home/ladyada/public_html/wiki/data/attic/tempcontroller/sensor.1267656717.txt.gz · Last modified: 2016/01/28 18:05 (external edit)
Page Tools
Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Share Alike 4.0 International
