Using a MAX6675 K-Type Thermocouple with Relay and Display

Using a MAX6675 K-Type Thermocouple with Relay and Display

This project demonstrates how to interface a MAX6675 K-type thermocouple with an Arduino, incorporating a relay for control and a display for temperature readings. This setup is invaluable for various applications where precise temperature monitoring and automated responses are needed. Here are some project ideas:

Overheat protection for sensitive electronics
Temperature-controlled incubator for biological experiments
Automated brewing system for coffee or beer
Industrial process monitoring and control
Environmental monitoring in a greenhouse or other controlled environment

Hardware/Components

To build this project, you will need the following components:

Arduino Uno (or compatible board)
MAX6675 K-type thermocouple module (in video at 00:58)
Relay module
TM1637 4-digit LED display module
Jumper wires
Connecting wires

Wiring Guide

The wiring is explained in the video (in video at 05:36). The specific connections depend on whether you are using a surface mount chip or a PCB module. Refer to the video for a detailed wiring diagram.

%%WIRING%%

Code Explanation

The Arduino code uses the MAX6675 library to read temperature values from the thermocouple. The key configurable parts of the code are:

Thermocouple pin definitions: thermoDO, thermoCS, and thermoCLK (in video at [03:53]). These pins need to be adjusted according to your wiring scheme.
Relay control pin: Pin 10 is used to control the relay (in video at [05:36]). Change this if needed.
Display configuration (if used): The code includes sections for configuring the TM1637 display. Adjust the CLK and DIO pins if necessary (in video at [03:53]).

The code includes functions to read temperature in Celsius and Fahrenheit. A crucial part of the code is the conditional statement that checks if the temperature exceeds a threshold (80.0�C in this example). If it does, the relay is activated (pin 10 goes LOW).


// If temperature goes above 80.0C, turn the relay ON
if(thermocouple.readCelsius() > 80.00){
  digitalWrite(10, LOW);// Set pin 10 LOW
} else {
  digitalWrite(10, HIGH);// Set pin 10 HIGH
}

Live Project/Demonstration

The video demonstrates the project in action (in video at 06:59). The sensor accurately reads the ambient temperature and increases when heated. The relay functionality is also showcased.