Thermocouple used correctly release date need to be aware of five aspects: 2019 - 02 - Number 13 reading: 1

Thermocouple in the development of measuring sensor precision is highest, economy the best product, so it became the most widely in our use of temperature measuring element of a type, it directly measure temperature, and the temperature signals into a thermoelectric emfs, through electrical instrument ( Secondary instrument) Convert the temperature of the measured medium. In order to improve measurement accuracy, reduce the measuring error, prolong the service life of thermocouple, requires the user should not only have the instrument operation skills, also should have physical, chemical and material aspects of knowledge. The author based on years of practice and refer to the relevant data, here is introduced in detail the thermocouple measurement error and the matters needing attention. In the process of using thermocouples, should focus on the following questions: 1, and dividing Numbers of thermocouple must be adopted by the temperature measurement and control instrument required thermocouple is consistent; 2, installation, the position of the thermocouple should leave the strong electromagnetic field, as far as possible to avoid the power the power cord, lest thermometer table to introduce additional thousand interference signal; 3, the rational selection of material, thermocouple outer casing diameter size, make sure there are enough strength, and to adapt to the environment atmosphere to be tested. Outside the casing surface should be clean, surface stains will increase the thermal resistance, measured temperature will be lower than the actual temperature; 4, thermocouple cannot long time work under the allowable temperature, otherwise will cause thermocouple material change, which resulted in increased measurement error. When measuring low temperature to reduce the thermal inertia of thermocouple, can be used to touch the bottom type or outcrop type thermocouple; 5, often should check whether the electrodes and the outer casing is in good condition, if it is found that local thinner diameter or outer casing surface corrosion is serious phenomenon, should stop to use, and replace the new thermocouple. One end of the thermocouple damage, damage can be removed, or is the measuring end and reference end refore, welding, still can continue to use after checking. Above is the small make up summary of thermocouple used correctly for everybody need pay attention to several aspects of the, I hope it can help you in the future use of.