Published November 5, 2020 © GPL3+

How to make digital temperature measurement device

In this tutorial, I will show you how to make digital temperature measurement device or digital thermometer with thermistor and arduino.

IntermediateFull instructions provided1,804

Things used in this project

Hardware components

Arduino Nano R3

Alphanumeric LCD, 16 x 2

Jumper wires (generic)

Breadboard (generic)

Resistor 10k ohm

Software apps and online services

Arduino IDE

Story

about device and thermistorThermistors (thermal resistors) are temperature dependent variable resistors. There are two types of thermistors, Positive Temperature Coefficient (PTC) and Negative Temperature Coefficient (NTC). When the temperature increases, PTC thermistor resistance will increase and NTC thermistor resistance will decrease. Thermistors are highly accurate (ranging from ± 0.05°C to ± 1.5°C), but only over a limited temperature range that is within about 50°C of a base temperature. The working temperature range for most thermistors is between 0°C and 100°C. The Arduino can’t measure resistance directly, it can only measure voltage. The Arduino will measure the voltage at a point between the thermistor and a known resistor. This is known as a voltage divider. The equation for a voltage divider is:In terms of the voltage divider in a thermistor circuit, the variables in the equation above are: This equation can be rearranged and simplified to solve for R2, the resistance of the thermistor: Finally, the Steinhart-Hart equation is used to convert the resistance of the thermistor to a temperature reading. The value of the resistor should be roughly equal to the resistance of your thermistor. You can use multimeter to find the ohm of thermistor.Please!

watch the complete video to know how it works……And like, share, comments on this video if you are new subscribe to my channel and follow on Arduino.I hope you enjoyed my project.Thanks!

Demo video

Device display

Normal temperature

Rised temperature when matchstick lights near it

Code

Arduino Code

#include <math.h>
#include "LiquidCrystal.h"
LiquidCrystal lcd(2,3,4,5,6,7);
float A = 1.009249522e-03, B = 2.378405444e-04, C = 2.019202697e-07;
float T,logRt,Tf,Tc;
float Thermistor(int Vo) {
 logRt = log(10000.0*((1024.0/Vo-1))); 
 T = (1.0 / (A + B*logRt + C*logRt*logRt*logRt)); 
 Tc = T - 273.15;                     // Convert Kelvin to Celcius
 Tf = (Tc * 1.8) + 32.0;              // Convert Kelvin to Fahrenheit
 return T;
}

void setup(){
 lcd.begin(16,2);
 lcd.setCursor(0,0);
 lcd.print(" Digital");
 lcd.setCursor(0,1);
 lcd.print(" Temperature");
 delay(8000);
 lcd.clear();
 lcd.print(" Shashwat__Raj");
 delay(8000);
 lcd.clear();
}

void loop() 
{
 lcd.setCursor(0,0);
  lcd.print("Temp:");
  lcd.print((Thermistor(analogRead(0))));
  lcd.print("k ");
 
 lcd.setCursor(0,1);
  lcd.print((Tc));
  lcd.print(" C ;");

 lcd.setCursor(9,1);
  lcd.print((Tf));
  lcd.print(" F");
 delay(800);
}