How to make sure the thermocouple is good or bad
Time:2015-08-06 08:49
First determine the appearance of the thermocouple there is no problem, good or bad, have to be determined by testing to.
Thermocouple special thermocouple to be tested is put on the ceramic casing, and the standard platinum-rhodium thermocouple placed into a tube furnace, the hot end of the insertion tube furnace in a porous, soaking with a metal made of nickel cylinders. The cold junction compensation for each wire into the ice-water mixture to keep the zero degrees Celsius container.
The tube furnace is maintained at the maximum allowable temperature thermocouple, and remain stable in this range. It has been tested and qualified with a time of benefits Bosideng potentiometer, measured and tested standard thermocouple thermocouple thermoelectric power generated difference and recorded.
The thermoelectric potential difference recorded look-up table to detect respective temperatures, if the measured thermocouple tolerance can be determined to be ineligible.
This tube furnace, not analysis of silicon carbide tube furnace chemical use.
For the failure of the thermocouple can be cut off from the hot end of a short, re-welding. Welding method is very simple, ordinary nickel-chromium thermocouple can be adjusted to a lower voltage with auto-transformers, with two thermocouple wire and into a pole, another pole with a carbon rod, direct ignition of the arc, two thermocouple wire will melt into a small spherical head. This operation is not difficult, you can adjust the voltage, will soon grasp. This welding using autotransformer insulation should be careful to ensure safety.
Of precious platinum and rhodium thermocouple welding, it is another way. The power surge after a pole inserted into an aqueous solution of sodium chloride, and the other pole is screwed together thermocouples, thermocouples with insulating clamp to live, tap the surface of the solution, across the thermocouple can be fused.