Thermocouple vs thermistor



  • I have the opportunity to by a bed heater that has a K type thermocouple in.
    Is there any reason I shouldn't go with this? Am I losing anything if I go for a thermocouple rather than thermistor or PT1000?



  • @jay_s_uk More susceptible to noise I believe and of course, you'll need a daughter board which adds cost.



  • @jay_s_uk Thermocouples are low mass and react to temperature changes quickly, and operate over much wider range than thermistors. But you don't need that in a massive printer bed that will take time to heat up and operates at relatively low temperature. The wires used for thermocouples usually aren't very flexible, so not a good idea in a moving print bed. If you clip the wires shorter and try to attach more flexible leads, you create inaccuracies because the new metal to metal junctions created act as thermocouples, too. And then there's the problem of interfacing it to the controller...

    Thermistors operate fine at bed temperatures, and react to changes more than fast enough, and connect directly to the controller board without any additional interfaces.

    There's not much point in using a thermocouple for a printer's bed.



  • @mrehorstdmd thanks for the detailed answer. I'll make some more enquires with the supplier


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