Setting up a new thermistor

jmpinc · April 2018

I was looking for a higher temperature thermistor, but when I looked for a Semitec 104GT-2 the listings I saw that it had been replaced with Semitec 104NT-4. I eventually found the table for it and set up a custom table in the Repetier configuration tool. However, it does not look right. Here's what I've got when I look at Configuration.h in Arduino:

#define USER_THERMISTORTABLE0 {{0,2400},{0,2320},{0,2240},{0,2160},{0,2080},{0,2000},{0,1920},{0,1840},{0,1760},{0,1680},{0,1600},{0,1520},{1,1440},{1,1280},{2,1120},{3,960},{9,640},{44,320},{287,0}}

Seems like there are a lot of 0 values there. I'm attaching a screenshot of the configuration page where I entered the table in case that helps diagnose what the problem seems to be. Also, how many entries should a 'good' table have. I had 18 entries, which seemed okay, but a cursory google search hasn't suggested a good number.

Thanks in advance.

Image: https://forum.repetier.com/uploads/editor/10/hy9xhfmgkic5.png

Repetier · April 2018

The resistances make no sense. At 25°C it is 100k = 100000. My guess is you forgot to multiply with 1000 so you get ohm and not kohm.

jmpinc · April 2018

Thank you. That was the critical bit of info I was lacking. KOhms, not Ohms.

Setting up a new thermistor

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