PT100 is suitable for most of the temperature measurement below 400°C, but usually the temperature of the household natural gas stove can reach over 800°C, and the temperature of the pottery kiln or high-power electric furnace can be more than 1000°C. The K-type thermocouple are commonly used in such ultra-high temperature scenes.

The digital K-type high temperature sensor consists of a signal amplification conversion module and a sheathed K-type thermocouple probe. When the K-type thermocouple probe is placed near a high-temperature heat source, the probe generates a small voltage proportional to the temperature due to the thermoelectric effect. The module uses a MAX31855K dedicated chip to amplify this small voltage, convert it to digital signals, and compensate accordingly. The temperature readings can be read through Gravity I2C interface. The module can measure extremely wide temperature ranging from -270°C to 1372°C, the error from -200°C to 700°C is within ±2°C, and the error from 700°C to 1350°C is within ±4°C. The attached K-type thermocouple can measure up to 800 °C with error within ± 2.5 °C.



Signal Amplification Conversion Module

Armored K-Type Thermocouple Probe


Board Overview

Label Name Description
1 VCC Power VCC(3.3~5.5V)
2 GND Power GND
3 SCL I2C Clock Signal
4 SDA I2C Data Signal
5 BLUE- K type thermocouple negative electrode
6 RED+ K type thermocouple positive electrode

Arduino Tutorial


Connection Diagram

Read Temperature

  * file ReadTemp.ino
  * Connect MAX31855 to arduino via I2C interface,then download this example
  * @n open serial monitor to check the temperature.
  * Copyright   [DFRobot](, 2016
  * Copyright   GNU Lesser General Public License
  * version  V0.1
  * date  2018-3-6

#include <DFRobot_MAX31855.h>

DFRobot_MAX31855 max31855;

void setup(){
  /*Set baudrate*/

void loop(){
  int stat;
  /*Detect I2C device*/
  stat = max31855.scan();
    Serial.println("No I2C devices!");
    /*Read Celsius*/
    float temp = max31855.readCelsius();
    Serial.println(" ℃");


Raspberry Pi Tutorial


Connection Diagram


1.Start the I2C interface of the Raspberry Pi. If it is already open, skip this step. Open Terminal, type the following command, and press Enter:

 pi@raspberrypi:~ $ sudo raspi-config

Then use the up and down keys to select “5 Interfacing Options” -> “P5 I2C” and press Enter to confirm “YES”. Reboot the Raspberry Pi.

2.Installing Python libraries and git (networking required). If it is already installed, skip this step. In the Terminal, type the following commands, and press Enter:

pi@raspberrypi:~ $ sudo apt-get update
pi@raspberrypi:~ $ sudo pip install wiringpi

3.Download the driver library and run it. In Terminal, type the following commands, and press Enter:

pi@raspberrypi:~ $ git clone
pi@raspberrypi:~ $ cd ~/DFRobot_MAX31855/RaspberryPi
pi@raspberrypi:~/DFRobot_MAX31855/RaspberryPi $ python

Read Temperature

pi@raspberrypi:~/DFRobot_MAX31855/RaspberryPi/python $ cd readTemp
pi@raspberrypi:~/DFRobot_MAX31855/RaspbeeryPi/python/readTemp $ python



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