How to fix a soldering iron that doesn’t heat up after being powered on
There are two situations when the soldering iron does not heat up after being powered on. One is that it does not heat up at all after being powered on. This may be because the soldering iron core or the power cord is damaged. At this time, you can use a digital multimeter to measure the resistance between the plugs of the power cord of the soldering iron. Generally, the resistance of a normal soldering iron is between one hundred and ten ohms and one or two thousand ohms (the greater the power of the soldering iron, the smaller the measured resistance). If the measured resistance is infinite, it may be that the soldering iron core or the power cord is damaged. Just replace the soldering iron core or power cord.
If the soldering iron is still slightly hot for a long time after being powered on and cannot melt the solder wire, it may be that a thick oxide layer is attached to the inner wall of the soldering iron tip, which prevents the heat from the soldering iron core from being transferred to the soldering iron tip. Some cheap electric soldering irons do not have temperature adjustment and constant temperature functions, and use a copper soldering iron tip as shown in the picture above. If it is heated for a long time, the copper soldering iron tip will be easily oxidized at high temperatures and produce a thermal resistance.
If the soldering iron head is severely oxidized and cannot weld normally, it is recommended to replace it with a better temperature-adjustable soldering iron. After all, the quality of the soldering iron has a great influence on the quality of welding. The temperature-adjustable soldering iron shown in the picture above costs only more than 20 yuan. It has a built-in temperature adjustment circuit, and the soldering iron tip is made of alloy, which is not easy to oxidize and turn black at high temperatures, making it very convenient to use.
The electric soldering iron is composed of a soldering iron head, a soldering iron core, a metal shell, a wooden (plastic) handle, a terminal post and a power cord. The heat source of the soldering iron is the soldering iron core installed on the head. As long as the soldering iron core is powered on, it can work normally.
If the soldering iron is not hot, first use a multimeter to measure the two pins of the power plug. Under normal circumstances, the resistance should be between a few hundred to several thousand ohms. If it is in an open circuit state, you need to open the handle and check whether the wiring is firm and reliable. Then measure the terminals,
The connection between the terminal and the lead of the soldering iron core is a place where problems are more likely to occur. Sometimes the connection seems to be good but is actually disconnected, so check carefully. If the soldering iron core is damaged, just buy a new one and replace it.
