Precautions for manual electric soldering iron welding
1) Master the heating time well
Preheat the workpiece. Establishing good flow and wetting requires preheating. Pads, holes, and component pins with good solderability characteristics will help to form good solder joints in the shortest possible time.
At elevated temperatures, short time is the key to avoiding damage to the substrate, damage to the bonding between the solder pad and substrate, and excessive metal to metal growth. Solder spots exposed to repeated Temperature cycling above the liquefaction temperature of Tg of solder and/or substrate may suffer degradation of reliability accumulation.
The method is to complete the welding point in less than 5 seconds, preferably around 3 seconds. This time includes all necessary operations required to generate connections, and the shorter the time, the better, while ensuring that the solder wets the solder.
2) Maintain appropriate temperature
Keep the soldering iron tip in the appropriate temperature range. The general experience is that the temperature of the soldering iron head is 50 ℃ higher than the melting temperature of the solder, which is more suitable.
3) It is incorrect to apply force to the solder joint with a soldering iron. It will cause damage to the weldment. For example, the welding points of Potentiometer, switch and connector are often fixed on plastic components, and the result of force application is likely to cause component failure.
In addition, using an electric soldering iron belongs to high voltage operation, and it is necessary to pay attention to safe use of electricity.
Many electric soldering irons have three terminals, two of which are connected to the soldering iron core for connecting to a 220V AC power source, and the other is connected to the soldering iron shell as a grounding protection terminal for connecting to a ground wire. For safety reasons, it is best to use a multimeter to identify whether the soldering iron core is disconnected or mixed before use.
The resistance of the iron core for a typical 20-30W electric soldering iron is 1500-2500 ohms.
