Bed thermistor accuracy: over-reporting?
Heya
Loving my Mk2 so far, got some great prints right outta the box (well, after building the kit) that are right up there with my other two printers I've meticulously calibrated over the years. One thing that's confusing me though is the heated bed temperature. It seems to be over-reporting the temperature, since it reports 55*C but is only slightly warm to the touch. Assuming body temp is 37*, I'd think a temperature delta of 18 degrees would feel much warmer. I don't have a thermocouple, but a digital meat thermometer got up to ~46* when placed directly on top of it.
Any idea what might be up? I've seen reports that thermistors can get caught and separate from the bed, but that doesn't seem to apply as it would cause the temperature to be underreported since it's reading the bed temperature through an air gap.
Re: Bed thermistor accuracy: over-reporting?
The bed has zonal heating; the corners are hotter than the centre.
The bed thermistor is on the underside so should report slightly lower temperature than the top of the bed when it is positioned.
Thermistors used in this printer should be most accurate at 25 degrees C; at higher temps they may be slightly less accurate.
Thing is, if the part sticks, all is good.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…