Thermistor Issue

Discussion in 'E3D-v6 and Lite6' started by TheJimReaper, Jul 20, 2018.

  1. TheJimReaper

    TheJimReaper Member

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    Hi guys,

    I bought the E3D V6 back in May, I had an issue with a small blockage a few days ago, after clearing it out and still having a few problems I ended up having to replace the nozzle. After replacing the nozzle I had some oozing! Thankfully I caught it early and there wasn't very much. Cleaned everything up and now I seem to be having an issue with the thermistor not reading the temps properly! I'm printing with the nozzle temp of 200°C, but the temps are fluctuating between 175°C and 205°C.
    I did get a few thermal runaway errors due to a loose connection which I fixed, but now I have this fluctuation!

    Is there a way to test the thermistor to make sure it's working properly, could it be something else?

    Any help would be appreciated.

    Cheers

    Jim
     
  2. Rob Heinzonly

    Rob Heinzonly Well-Known Member

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    You could test the reststance of the thermistor. At 30 deg C an E3D thermistor should have a resistance of 76.8 ohm (just measured it, yes it is bloody hot in Holland ;-)
     
  3. Antoine

    Antoine Well-Known Member
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    This seems more like a temperature stability issue. Have you run a PID autotune? Thermistors often have slight offsets from the actual temperature, but wouldn't give you different readings for the same temperature.
     
  4. elmoret

    elmoret Administrator

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    77kohm sounds about right for a thermistor at that temperature. 77ohm does not.
     
  5. TheJimReaper

    TheJimReaper Member

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    Hi guys, Thanks for the replies. I did do the PID tuning and still had the same issue, however whilst trying to test the thermistor and other bits. My wife who was helping me as I have arthritic hands broke the wires to the thermistor then whilst trying to remove the thermistor so I could get a replacement, she went and broke the nozzle and throat in the heat block!! Don't ask me how!!

    So, she bought me a whole new hotend set up!!

    Thanks anyway guys
     

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