I just used what was supposed to be a 100k ohm thermistor to hotend and now it is reading 83C instead of the "around" 29C that it should be reading which leads me to think they sent me 10k Ohm instead of the 100k Ohm that they should be.

My question is can I just add a resistor inline to bring it up to 100k Ohm and if so what value resistor and please don't say 1k Ohm as I ran out of those and my new batch is still on the long boat from China,

Edited 1 time(s). Last edit at 08/02/2018 03:12PM by thequestor.

Every thermistor has a distinct curve, just adding a resistor will not help at all since the curve will be totally warped.
Get a correct thermistor and spare yourself a whole lot of trouble.

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sry, miss read the question.

No a resistor in series with a thermistor will not work as needed.

Edited 2 time(s). Last edit at 08/04/2018 06:00AM by obewan.

Wouldn't that change the temperature response? Since regular resistors aren't made to work like thermistors, you'll get innacurate temperature readings which could be dangerous.

The Short Answer is no.
If at room temp it measures close to 10K omh then you do have a 10K Omh. if it does measure close to 100K at room temp then there is something else wrong.

Quote
thequestor
I just used what was supposed to be a 100k ohm thermistor to hotend and now it is reading 83C instead of the "around" 29C that it should be reading which leads me to think they sent me 10k Ohm instead of the 100k Ohm that they should be.

My question is can I just add a resistor inline to bring it up to 100k Ohm and if so what value resistor and please don't say 1k Ohm as I ran out of those and my new batch is still on the long boat from China,

If you are using Marlin, look in your configuration.h file for a thermistor profile that matches your thermistor. There are several 100K ones. I did this with a system and checked temperatures with a thermocouple on my DVM. A bit of a pain, but could solve your issue.

DLC

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