Electric soldering iron thermometer high temperature temperature line
The temperature sensing wire is an important small part on the electric soldering iron thermometer. It measures the temperature of 0-600°C, can resist corrosion and oxidation, and is easy to replace. The electric soldering iron measures the temperature by touching the temperature sensing wire.
There are many types of temperature sensing wires, commonly known as "thermocouples".
The working principle of the temperature sensing line:
There are 3 terminals on the temperature sensing line, 2 of which are positive and negative, and the third is for automatic compensation. In terms of design of the temperature sensing line, some are two-wire system, and some are three-wire system. Short-circuit the "+/-" of the temperature sensing line with the third one respectively, and the output temperature is normal as the end. However, the basic principle is to use the corresponding relationship between a certain material and the temperature change, and form a closed loop through two different material conductors. When there is a temperature gradient at both ends, a current will flow through the loop. At this time, between the two ends There is electromotive force - thermal electromotive force, which is the so-called "Seebeck effect", and then the potential signal is amplified by the amplifying circuit, converted into AD signal and displayed by LED or pointer.
When testing soldering iron tips, pay attention to:
1. Before testing the temperature of the electric soldering iron, the temperature of the electric soldering iron should be raised to a temperature that can normally melt the tin wire before testing;
2. Keep the electric soldering iron and the temperature sensing wire clean, remove the residual tin, put the electric soldering iron close to the test area, and then add a little tin bead to the soldering iron tip;
3. Put the electric soldering iron in the middle of the temperature sensing line, and make it 30 degrees flat with the temperature sensing line, and keep it for about 4-5 seconds. The temperature of the soldering iron tip is displayed.
