for anyone who wants to work with thermistors other resistance-type temperature sensors here the basic method of working with them. you should be able to work with all types of them.

the basic sketch

```
#include <math.h>
/// Example NTC 10K
/// Using the beta constant -- less acurate ////
float Ro = 10, Beta = 3950; //Nominal resistance 10K @25C , Beta constant
float Rseries = 10;// Series resistor 10K
float To = 298.15; // Nominal Temperature @25C
//Example for PT1000
///// using Steinhart-Hart Coefficients more accurate //////
float A = 0.06501312861989986; /// for the PT1000 use a 1k resistor
float B = -0.01161716353567784;
float C = 0.00005732815001133613;
void setup() {
Serial.begin(115000);
}
void loop() {
/*Read analog outputof NTC module,
i.e the voltage across the thermistor */
float Vi = analogRead(A0) * (5.0 / 1023.0);
//Convert voltage measured to resistance value
//All Resistance are in kilo ohms.
float R = (Vi * Rseries) / (5 - Vi);
float ohm = R*1000;
/*Use R value in steinhart and hart equation
Calculate temperature value in kelvin*/
float T = 1 / ((1 / To) + ((log(R / Ro)) / Beta));
float T_SH = 1 / (A + (B * log(ohm)) + (C * ( log(ohm) * log(ohm) * log(ohm))));
float Tc = T - 273.15; // Converting kelvin to celsius
float Tc_SH = T_SH - 273.15;
float Tf = Tc * 9.0 / 5.0 + 32.0; // Converting celsius to Fahrenheit
float Tf_SH = Tc_SH * 9.0 / 5.0 + 32.0;
Serial.print("ohms = "); Serial.println(ohm);
Serial.print("kilo ohms = "); Serial.println(R);
Serial.println("Beta Constant");
Serial.println((String)"Temperature in celsius :" + Tc + "°C");
Serial.println((String)"Temperature in Fahrenheit :" + Tf + "°F");
Serial.println ("Steinhart-Hart Coefficients");
Serial.println((String)"Temperature in celsius :" + Tc_SH + "°C");
Serial.println((String)"Temperature in Fahrenheit :" + Tf_SH + "°F");
Serial.println(" ");
delay(1000);
}
```

now if you know your sensor type you can look up the resistant table or the beta constant

example for the NTC 10k B=3950 for the beta constant at 25C or the resistance :

at 0C the resistance is 33620, at 60C it is 2486 and at 120C it is 407

for the PT1000

at 0C the resistance is 1000 at 60C it is 1232 and at 120C it is 1460

simply enter those numbers into one of calculators

http://www.nonmetalhail.com/projects/thermistor/themistor.html

or this one if you want to use the Beta constant ( it easier)

https://www.thinksrs.com/downloads/programs/therm%20calc/ntccalibrator/ntccalculator.html

for an unknown thermistor simply measure its resistance at 3 different temperatures with in your working range. ie 0C 60C and 100C if the thermistor is a high temperature one then say 0c 100C and 200C

and use a resistor that is suitable for your sensor if at 25c it 10k use a 10k. if the sensor works in the 1k range uses a 1 k and if lower use a lower one

the above sketch displays the ohms when testing just it tosee if it has same ohm reading as what the sensor gives directly using multimeter