Let me outline a little known fact or two:
Part 1
1 The cable that connects to the themrocouple is a bimetallic pair - one cable in the pair is positive and the other is negative,
2 Note that each type of cable is specific to the thermocouple type.
3 Change your matching cable if you change the thermocouple - temperature readings will be way off if you dont do this.
Part 2
To ensure you setup your connections correctly, follow this process:-
1 Disconnect the thermocouple (the probe end)
2 Twist the end of the connecting cable so there is a "good" connection (the other ends are connected to the Temperature Points at the "box")
3 Heat the end of the twisted cable. If your reading goes upscale it is connected correctly. If it goes downscale it is wrong so reverse your meter connections. Retest (you may have replaced them the same as before). Believe me that IS possible.
4 Connect the twin cable to your thermocouple. Reheat and check for a rise in temperature. If temperature goes down - reverse the thermocouple connection and retest.
If temperatures have been around half what is expected this is a sure sign of incorrect terminal hookup.
I have had reports of a kiln melt-down due to this problem despite clear instructions as to how to hook up the temperature controller.
Essentially you will be reading a lower temperature than what is being sensed at the thermocouple.
Hope this helps you as an experimenter.........
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