So first of all, I'm a mechanical engineer and a terrible electrical engineer.
I'm trying to build a failsafe for a heating element. This heater has an integrated k-type thermocouple and is limited to 350 degrees C. At this temperature, the thermocouple should produce a voltage of about 14mVdc. The heater is powered through a solid state relay which conveniently asks for a 12Vdc control voltage in order to relay the mains voltage.
I wish to use the thermocouple output voltage to control a switch. Once a voltage of 14mVdc is produced, the 12Vdc control voltage line should be broken which powers off the heating element.
Unfortunately, I have no clue how to go about this problem. I can imagine that the thermocouple voltage needs to be amplified but that's about it.