Is a high or low power iron better?
There are various types of power for electrified iron, ranging from 15 watts and 20 watts for smaller ones, 200 watts and 300 watts for larger ones, and 500 watts for pistol style ones. When performing welding work, the power of the soldering iron must be determined based on the welding object, and sometimes the power of the electric network iron must also be selected based on the climate season (winter, summer). Welding electronic components, using 15 watts to 20 watts is good, using 500 watts, a soldering iron will be a black hole, of course not good.
Whether the power selection is appropriate depends mainly on the melting and flow of the solder, which should not exceed three seconds. Too long can damage electronic components, too short can lead to unstable soldering, and the solder joints are not smooth.
Generally, it is recommended to use a soldering iron with a power of 20 watts for welding small components such as resistors, capacitors, transistors, and integrated blocks. In winter, it is recommended to increase the power by one level and use a soldering iron with a power of 25 watts. When welding large components such as heat sinks, transformers, shielding covers, or grounding large-area copper plates, it is recommended to use 35 watts to 40 watts. So, it is necessary to choose the appropriate power of the soldering iron according to the welding object, and there is no such thing as whether the power is too high or too low.
The electric soldering iron used has excessive power, which can easily burn out components (usually when the junction temperature of the transistor exceeds 200 ℃) and cause printed wires to detach from the substrate; The power of the soldering iron used is too low, the solder cannot be fully melted, the flux cannot evaporate, the solder joints are not smooth and firm, and it is easy to produce virtual soldering. Generally, it is used for soldering integrated circuits, printed circuit boards, CMOS circuits, decorative transistors, IC recorders, televisions, and conducting ordinary circuit experiments. It is generally recommended to use 20W. For repairing vacuum tube machines such as gallbladder machines and old instruments, 35W is recommended. For external heating type machines, 45W is recommended. For soldering the wiring of large transformers and grounding main lines on metal substrates, internal heating type 50W and external heating type 75W are used. If welding metal materials, an external heating soldering iron with a power of over 100W should be selected. If conditions permit, amateur radio enthusiasts can equip themselves with a 2OW internal heating type, a 35W internal or external heating type, and a 150W external heating type soldering iron, which can basically meet various welding needs.
