How to connect the three wires of the thermocouple?

Thermocouples are common components in circuits, do you know how they are wired? After reading this article, I hope it will be helpful to you. Wiring method: Thermocouples are used with matching secondary meters, and extension cables are used to connect thermocouples to the secondary meter. This voltage is very small, at the mV level, and needs to be divided into positive and negative poles.

Attention should be paid to the installation of thermocouples and thermal resistors, which is conducive to accurate temperature measurement, safe and easy maintenance, and does not affect equipment operation and production operations To meet the above requirements, when selecting the installation location and insertion depth of thermocouples and thermal resistors, attention must be paid to: 1. In order to ensure sufficient heat exchange between the measuring end of thermocouples and thermal resistors and the measured medium, the measuring point position should be selected reasonably, and thermocouples or thermal resistors should be avoided as much as possible near dead corners of valves, elbows, pipelines, and equipment. 2. Thermocouples and thermistors with protective sleeves have heat transfer and dissipation losses. In order to reduce measurement errors, thermocouples and thermistors should have sufficient insertion depth:

(1) For thermocouples used to measure the fluid temperature at the center of a pipeline, their measuring end should generally be inserted into the center of the pipeline (vertically or obliquely installed) If the diameter of the tested fluid pipeline is 200 millimeters, the insertion depth of the thermocouple or thermistor should be selected as 100 millimeters; (2) For temperature measurement of high temperature, high pressure, and high-speed fluids (such as main steam temperature), in order to reduce the resistance of the protective sleeve to the fluid and prevent the protective sleeve from breaking under the action of the fluid, shallow insertion of the protective tube or the use of a hot sleeve thermocouple can be adopted. The depth of insertion of the shallow insertion thermocouple protective sleeve into the main steam pipeline should not be less than 75mm; The standard insertion depth for hot sleeve thermocouples is 100mm; (3) If it is necessary to measure the temperature of the flue gas inside the flue, even though the diameter of the flue is 4m, a thermocouple or thermistor can be inserted at a depth of 1m; (4) When the insertion depth of the measuring element exceeds 1m, it should be installed vertically as much as possible, or support frames and protective sleeves should be added.

Thermocouple wiring diagram Thermocouple is a commonly used temperature measuring element in temperature measuring instruments. It directly measures temperature and converts the temperature signal into a thermoelectric potential signal, which is then converted into the temperature of the measured medium through electrical instruments (secondary instruments). The appearance of various thermocouples often varies greatly due to their needs, but their basic structures are roughly the same. They are usually composed of main parts such as hot electrodes, insulation sleeves, and junction boxes, and are usually used in conjunction with display instruments, recording instruments, and electronic regulators. Is it clear at a glance.