Types and power of commonly used soldering irons
There are two commonly used types of electric soldering irons: internally heated and externally heated. The iron tip of an internally heated electric soldering iron is located outside the heating wire, which heats quickly and is lightweight. The soldering head of an externally heated electric soldering iron is inserted into the heating wire, and although it heats slowly, it is relatively firm.
The electric soldering iron is heated directly with a 220V AC power supply. The power cord and the casing should be insulated, and the resistance between the power cord and the casing should be greater than 200M ohms.
Electronics enthusiasts usually use 30W, 35W, 40W, 45W, and 50W soldering irons. A high-power soldering iron has a smaller resistance of the heating wire. Ohm's Law derivation formula: R=U/I=U/I * U/U=U ^ 2/P
2. Precautions for using electric soldering iron
(1) Before using a newly purchased soldering iron, it must be dipped in a layer of tin (power on the soldering iron, and then use a tin bar close to the soldering iron head when the soldering iron is heated to a certain level). After using the soldering iron for a long time, file the soldering iron head bright, then heat it up with electricity, and dip the soldering iron head in a bit of rosin. When the rosin is smoking, tin should be applied, so that a layer of tin can be coated on the surface of the soldering iron head first.
(2) After the electric soldering iron is powered on, the temperature can reach over 250 degrees Celsius. When not in use, it should be placed on the soldering iron frame. However, when not in use for a long time, the power should be cut off to prevent the soldering iron tip from being burned (oxidized) by high temperature. To prevent electric soldering iron from damaging other components, especially power lines, if the insulation layer is burned by the soldering iron and not taken seriously, it can easily lead to safety accidents.
(3) Do not forcefully strike the electric soldering iron to avoid shaking the internal heating wire or lead of the soldering iron and causing malfunctions.
(4) After using an electric soldering iron for a period of time, there may be tin deposits left on the head of the soldering iron. Under the heating conditions of the soldering iron, we can gently wipe it with a damp cloth. If there are pits or oxidation blocks, they should be repaired with a fine grain file or the soldering iron head should be replaced directly.
