How to distinguish J, T and K thermocouple lines
Thermocouple wire is used to connect the cold end of the thermocouple to the display instrument in the control room to compensate the temperature of the cold end. And because of the variety of thermocouple, different models of thermocouple should be equipped with the corresponding thermocouple line. But in use, because a variety of thermocouple line is comprehensive use, many people cannot tell. Then I will tell you how to distinguish the J, T and K thermocouple lines.

1. K type thermocouple see the insulation layer color: through the insulation layer color to judge the dividing number of the thermocouple line, but this method is only limited to the thermocouple line, if the thermocouple compensation wire is not applicable.
One red and one yellow are K-marks
One red and one white is a J-mark
One red and one blue are T-marks

2. Look at the thermocouple wire - wire
A J-graded thermocouple wire, one of which is made of iron and can be held by a magnet;
J-type indexing thermocouple wire, one of the materials is copper, you can see the obvious yellow copper wire
The above two methods are just experience, not necessarily applicable to any occasion, if you must be very accurate judgment of the thermocouple line dividing number, you can try to measure the electromotive force.