What is the reason why the soldering iron does not heat up after being energized
If the soldering iron is not hot when it is powered on, it is usually because the power cord has fallen off or the core wire of the soldering iron is broken. When encountering this fault, you can use the R×lkn gear of the multimeter to measure both ends of the power plug. If the pointer of the multimeter does not move, it means that there is an open circuit fault.
First of all, check whether the lead wire of the plug itself is broken. If not, you can remove the bakelite handle, and then use a multimeter to measure the two leads of the soldering iron core. If the pointer of the multimeter still does not move, it means that the soldering iron core is damaged and the soldering iron core should be replaced. The resistance between the two leads of the 35W internal heating type soldering iron core is about 1.Skfl. If the measured resistance is normal, it means that the soldering iron core is good. The fault occurs in the power lead wire and the plug itself. Most of the faults are lead wire breakout.
To replace the soldering iron core, insert a new soldering iron core of the same specification into the connecting rod, fix the lead wire on the fixing screw, and tighten the terminal post. At the same time, pay attention to cut off the excess part of the soldering iron core lead wire to prevent short circuit between the two leads.
Electric soldering iron: A tool for electronic production and electrical maintenance. It is generally composed of a soldering iron head, a soldering iron core, a shell, a wooden handle, a power lead, a plug, etc. The main purpose is to weld components and wires.
The working principle of the electric soldering iron: After the power is turned on, the resistance wire of the soldering iron core generates heat, which is transmitted to the soldering iron tip, and the soldering iron tip melts the solder to work.
If the soldering iron is not hot, the main reason may be that the resistance wire in the soldering iron tip is blown. This is a vulnerable part of the soldering iron. Just replace the soldering iron core. However, the failure of the power cord and plug cannot be ruled out. Therefore, when the electric soldering iron is not hot, first check the power plug and power cord with a multimeter, and then check the soldering iron core
Welding method
Action essentials: first heat and then send tin, first remove tin and then remove soldering iron.
During the storage of electronic components, due to the effect of air oxidation, a layer of oxide film is attached to the component pins, and there are other dirt. Before welding, we must clean up the components and plate them with a layer of tin. In this way, the solder joints we welded are less likely to have virtual soldering.
Soldering temperature and soldering time
We should choose the appropriate temperature when soldering. The temperature should be higher than the soldering tin temperature. If it is too high, it is not good. If it is serious, the pad will fall off directly. It is better to smoke when the soldering iron tip contacts the rosin.
If the soldering time is too short, the temperature of the solder joints is too low, the solder joints are not fully melted, and the solder joints are rough and easy to cause false soldering. On the contrary, the soldering time is too long, the solder is easy to flow, and it is easy to cause the components to overheat and damage the components.
The amount of tin on the soldering point
We must master the amount of tin on the solder joints. The amount of solder on the solder joints should not be too small. If it is too small, the soldering will not be strong, and the solder joints will be flat, and the mechanical strength will be too poor. If there are too many, it is easy to cause a lot of appearance but the inside is not connected, and it becomes a bucket shape, which is extremely ugly. The solder should just submerge all the component leads on the soldering point, and the outline should be faintly visible.
