Hi guys,
I'm trying to read the temperature with a thermistor NTC 10k , as w know thermistors have just 2 outputs so it needs a resistor from 3.3v to send data, as i said i'm working with 10k thermistor and the resistor is 9,4kohm ( 2x4,7kOhm), i couldn't get it right the serial monitor showing that the thermistor didn't gave any data although i took the code ready from youtube
i want to know is the resistor capacity causing the problem or should i keep testing other codes
It is not about the resistor, it is about the "ratiometric" principle.
Which Arduino board do you use ?
The resistor can be 1k to 100k for a 10k NTC, you only lose accuracy.
If you have an Arduino Uno, and its voltage reference is default set to VCC (5V), then you need to power the NTC via the resistor with that same VCC (the 5V pin). You will read the exact same value with analogRead() even if the 5V changes or drops in voltage. That is called "ratiometric".
With a simple calculation, the accuracy is acceptable.
There are better calculations, but then you have to know the exact specifications of the NTC.
A list with values for the NTC is the most accurate.
Adafruit has the best tutorials: https://learn.adafruit.com/thermistor/
I'm using an esp8266
Keep testing other codes
A dev board, like a NodeMCU ?
Which has the wrong type of A/D for thermistors.
Forget about using thermistors with an ESP8266 or ESP32.
Use a digital temp sensor, like the DS18B20.
Leo..
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