How to connect thermocouples?


I am currently building a cooking thermometer using a thermocouple probe.
I saw that plugs like these
are made from the thermocouple material to avoid thermocouple junctions.
But how do I connect these to, say, this
Thermocouple Amplifier MAX31855 breakout board (MAX6675 upgrade) : ID 269 : $14.95 : Adafruit Industries, Unique & fun DIY electronics and kits

Do I need thermocouple wire? But even if I used that wire, there would be a copper/solder/wire junction at the PCB. What care do I have to take there? Is it acceptable to solder copper wire to the PCB and connect it to the plug with the screw terminals? Is is also still acceptable to solder screw terminals on the PCB and connect the wire there at that end?

Plenty of information on the web, e.g. Data Translation Data Acquisition Products

That does not answer my question, it only states the problem that I already stated.
There WILL be a junction somewhere, at least at the PCB. Now, the question is, what is better:

  • PCB/Copper-solder-copperwire-screwterminal or
  • PCB/Copper-solder-thermocouplewire-screwterminal
    I cannot see a distinct advantage in either of those, it more or less just shifts the junction.

I did NOT find "Plenty of information on the web", regarding this problem, only the general information you posted.

If you are connecting your TC directly to the module you are OK, the module has cold junction compensation built in, but if you want the TC farther away than the length of the TC wires you must use TC extension wire. You only need copper wire from module to Arduino.

More about thermocouples:

Why do I may I not use copper wire between the module and the socket/plug? I should just shift the junction from the module to the socket.

You have to know the temperature of the junction, where different materials cause a voltage difference. The cold junction compensation on the module takes into account the temperature in exactly this place. Shifting that "cold" junction to some arbitrary place, of an unknown temperature, will result in false readings.

TC extension wires cause the same offset voltage on both lines, not adding any errors. They differ from the TC materials in price, maximal temperature and other practical factors.