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Few words about the Adafruit thermocouple module. This nice little module features a couple of smart ideas:

• Use a fully integrated driver solution which outputs data on a SPI port (MAX31855)
• Any thermocouple assembly will fit on the header  (as long as it is a K type)
• 5V / 3.3V compliant (in other words UNO / DUE ready!)

Here is a picture of the assembled module

Nothing new under the sun, except for the header that is using female type connector instead of the standard male type connector which is delivered with the module. This helps the wiring with male/male jumper wires.

Here is a little trick from the field. If you are in doubt with the wire color (remember, a thermocouple has a polarity), use a simple magnet and check which wire attracts the magnet.

• If you use a K type thermocouple, the alumel wire will be attracted! Its color is usually yellow (check table below) and goes to the – port of the shield.
• If you use a J type thermocouple, the iron wire will be attracted! Its color is usually white (check table below) and goes to the + port of the shield.

Here is an illustration of the Adafruit K type thermocouple and a rare earth magnet sticking to the alumel wire.

Thermocouple color codes table:

HTH

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