Using MAX31855 Thermocouple Amplifier with Raspberry Pi

30/04/2013

This project use the MAX31855 Thermocouple Amplifier breakout board. Together with a K-type thermocouple it will allow the Raspberry Pi to do temperature measurement from -200°C to +1350°C in 0.25 degree increments.

The MAX31855 breakout board uses a SPI interface. This can be connected to the Quick2Wire Interface board then to the Raspberry Pi.

Parts List

Hardware Setup

The MAX31885 breakout board has a six way 0.1″ connector. This will need to be connected to the SPI connector of the Quick2Wire Interface board.

The connection details are:
A ready made cable is available.

Software Setup

Install the Quick2Wire Python library.
Install the MAX31855 driver (thanks to Tuckie) by typing this at the prompt:

git clone git://github.com/Tuckie/max31855.git

then change into the directory:

cd max31855

You will now need to edit the max31855.py file to change the chip select line and to degree C unit.

nano max31855.py

Scroll to the end of the file and find this line:

thermocouple = MAX31855(1, "f")

change it to

thermocouple = MAX31855(0, "c")

Press CTRL X then y to save and exit. Now run the script by typing:

python3 max31855.py

Should see something like this:

Touch the thermocouple and you should see the temperature rises.

Short URL:

Tags: , ,

Comments are closed.