Thermocouple vs Thermistor

Test comparing Thermocouple vs Thermistor

I originally wanted to just calibrate the thermistor table I used in my FW, since I remember that Camiel from Mendel-parts was moaning that his table was horrible and it affected his prints, I now just guess that his table wasn't made for his thermistor. I used one generated exactly for my thermistor by createTemperatureLookup.py from SVN. So I crated fake heater with both Thermocouple and Thermistor and written small sketch in Arduino to generate table, BUT I did want to simply try how imprecise it is. Then I was shocked, both readings were pretty close, actually biggest deviation was 3°C. You can see the graphs under and also download the Arduino sketch and sample data.

My verdict, is that both technologies are good for heaters and heatbeds, the precision is mainly affected by mounting on heater. Also be carefull to use precision resistors for thermistor circuits, thats all :-)

For more details see the following pages here for RepRap use of Thermistors and Thermocouples. There is abundant theory on the Wikipedia pages for [thermistors] and [thermocouples].

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Files

FILE ID#	TYPE	DESCRIPTION	AVAILABLE FORMATS	CREATED/RESERVED BY
Arduino code and data	PDE CSV XLS	Data	.zip	--Prusajr 12:08, February 5, 2011 (UTC)