Nice to see that you are discussing my project AxxSolder here! And sorry for not writing in Turkish.
Just wanted to say that I believe that what adgd.ru claims regarding the C245 pinout can seem correct if you measure the thermocouple voltage while externally heating the tip, as well as applying a current to heat up the tip.
Even for the pinout I claim (using my nomenclature) of RED, GREEN and BLUE terminal, you can:
Heat up the tip by applying a voltage over BLUE-GREEN.
Measure TC voltage over GREEN-RED.
This because a thermocouple is just two dissimilar metals (with close to zero resistance) joined at one point and in the case of JBC tips you can without problem draw a large current through the TC junction and you do not see any difference in your measurement when you heat up the tip if you flow current through the TC or not.
I have since my last post on EEVBlog Forum discovered that there are probably not only one thermocouple element within the C245 series tips. There are 3 points where two dissimilar materials are joined within the tip, thus forming 3 TC elements.
Two are having their polarity reversed compare to the third, canceling out the total seeback effect while measuring the voltage from GREEN to BLUE.
I have updated the pictures and text describing my cross-section measurements on EEVBlog Forum:
https://www.eevblog.com/forum/projects/axxsolder-jbc-soldering-controller/msg5124267/#msg5124267
Feel free to ask questions if you have or engage in the project!
Br.
Axel Johansson