Thermal resistance and thermocouple are two common temperature measuring elements. Here we will introduce how to quickly distinguish these two thermometers
Operation method
[Look at the nameplate] The nameplate is generally marked with thermal resistance or thermocouple, or its graduation number. The graduation number of thermal resistance mainly includes: Pt10, Pt100, Pt1000, Cu50, Cu100 The graduation number of thermocouple mainly includes: S B、E、K、R、J、T
[See the number of wires] The thermal resistance is generally a three wire system with six wires in two branches; Single thermal resistor also has four wire system, and very few use two wire system; Thermocouples are generally two-wire system, with two branches and four wires.
[See wiring type] The thermal resistance generally uses ordinary copper wire; Due to the particularity of the thermocouple's temperature measurement principle, the compensation wire corresponding to its graduation number needs to be selected.
[Check the temperature transmitter] Generally, the temperature transmitter is marked with a graduation number, or the 475 communication manual operator can check its graduation number for judgment
[Resistance measurement] Measure the resistance with a multimeter; Under normal circumstances, the resistance of the thermocouple is very small, only a few Ohms; The resistance value of Pt100 thermal resistance is more than 100 Ω at room temperature.
[See the type of safety barrier] If it is in the cabinet room, you can quickly judge the type of thermometer by the type of safety barrier. For example, KN5072 is used for thermal resistance, and KN5073 is used for thermocouple
