Hi and thank you for your post. Sorry for the difficulty you are facing.
The ADC11 is a data logger (or more correctly an acquisition unit) that measures voltages from 0 -2.5V, it has multiple inputs. By using the terminal board you have the flexibility to do many things. Attenuating larger voltages, putting shunt resistors, or even creating some circuitry to measure temperature (thermocouples, thermistors or even an integrated circuit sensor). The terminal board guide gives you some instructions on how to do this:http://www.picotech.com/document/pdf/ad ... ons-en.pdf
The reason why you just can plug in a thermocouple is you need to take into account cold junction compensation. This why you have to buy a CJC chip.
If you wanted a dedicate thermocouple device you would need to go for the USB-TC08 which can take 8 thermocouple inputs from all thermocouple types (it uses mini thermocouple connectors).http://www.picotech.com/thermocouple.html