Describes the characteristics of the thermocouple temperature sensor

Temperature sensor using the current very high rate in the industrial production , industrial development and use Crankshaft Positioning Sensor is currently running efficiency is very convenient to use the industrial automation , the temperature sensor is currently preferred product the thermocouple , the thermocouple is a a sensor measuring temperature , and thermal resistance are the same as the Camshaft Positioning Sensor , the two different materials a and B conductors or semiconductors welded together to form a closed loop, when two conductors a and B attachment between points 1 and 2 when the temperature difference between the two will generate an electromotive force , and thus forming a loop of current, a phenomenon known thermoelectric effect . Is called the Seebeck effect . Thermocouple probe is to use this effect to work . First, the nature of the signal , the thermal resistance is the resistance itself , temperature changes, the thermal resistor to generate positive or negative change in resistance ; the thermocouple, the induced voltage changes, he is changed with temperature . Second, Engine Water Temperature Sensor detect the temperature range is not the same, the general resistance test temperature range 0-150 ° , the maximum measuring range of up to 600 degrees ( of course, negative temperature can be detected ) . Third, from the material of resistance, which is a metal material having a metallic material changes in temperature-sensitive , bimetallic thermocouple materials , both of two different metals , due to temperature changes in the two wires of two different end generates a potential difference . Four , PLC corresponding thermal resistance and thermocouple input module is not the same , this sentence is not a problem , but generally have direct access to the PLC 4 ~ 20ma signals, and thermal resistance and thermocouple generally with transmitter only access PLC. If you do not have access to the DCS , then use the transmitter up ! Thermal resistance is the RTD signal , thermocouple is TC signal ! Five , PLC also has RTD and Thermocouple modules can be directly input resistance and thermocouple signals. Six , thermocouple J, T, N, K, S and other models , there are specific resistance expensive , there are also cheaper than the resistance , but the count compensation wire , thermocouple total cost will be high .