How to improve the welding quality of electric soldering iron
1. When using an electric soldering iron for welding, it is necessary to ensure that each solder joint is firmly welded and in good contact to ensure welding quality.
2. Good solder joints require bright tin spots, smooth and no burrs, and moderate tin content. Tin and solder are firmly fused. There should be no false welding and false welding.
3. Pay attention to prevent the problem of false welding and false welding: virtual welding means that only a small amount of tin is welded at the solder joint, resulting in poor contact, sometimes on and off. False welding means that it seems to be welded on the surface, but in fact it is not welded. Sometimes the lead wire will be pulled out from the solder joint when it is pulled out by hand.
Only after a large number of serious welding practices can these two major problems be avoided.
4. When soldering the circuit board, the time must be controlled. If the time is too long, the circuit board will be burnt, or the copper foil will fall off. When removing components from the circuit board, stick the tip of the electric soldering iron on the solder joint, and pull out the component after the tin on the solder joint melts.
5. Flux (rosin and soldering oil) is the key to welding. Fresh rosin and non-corrosive soldering oil are helpful for high-quality welding, and can make the surface clean and beautiful. Use multi-purpose flux.
Causes of electric leakage of electric soldering iron
The reason for the leakage of the soldering iron is mainly caused by the leakage of the soldering iron core.
The soldering iron core is composed of a heating wire, an insulating layer support and an insulating layer. When the insulating layer is subjected to moisture or aging for a long time, the insulation degree may decrease, resulting in leakage of the soldering iron core. Then it passes through the heat transfer shell of the electric soldering iron and the tip of the soldering iron.
The handle of the electric soldering iron will also leak electricity after excessive aging.
After electric leakage occurs in the electric soldering iron, the problem is very serious, and it is very easy to cause electric shock accidents, which is extremely harmful to people and electronic and electrical equipment to be repaired. Please replace the soldering iron core and leakage parts immediately, and replace them as a whole if necessary.
How to deal with electric leakage of electric iron
1. First adjust the multimeter to the AC voltage position, connect the black test lead to the ground, and connect the red test lead to the tip of the electric soldering iron. Observe whether the multimeter has a reading. If there is a reading, it proves that the electric soldering iron has leakage and needs to be repaired.
2. Disassemble the electric soldering iron, find the internal grounding mark, and then find the resistor connected to the circuit board along the grounding wire, and measure its resistance value. If it exceeds 5 ohms, it is judged to be burnt and needs to be replaced (leakage is extremely large. In some cases, the resistor is damaged), and if the resistance value is normal, please confirm whether the contact of the soldering iron plug is good.
3. Remove the burnt resistor and replace it with a new one. Note that although the resistance value of this resistor is 0 ohms, it plays a protective role and must not be short-circuited here!
4. After the replacement, use a multimeter to confirm the resistance value between the remote measurement of the resistance and the ground.
5. After the repair is completed, use a multimeter to confirm the resistance value between the soldering iron tip and the ground wire. If the resistance value is within 2 ohms, it proves that the repair is successful.
