1) The large leakage current of LED leads to the failure of PN junction, which causes the LED lamp decoration point not to light up, which generally does not affect the operation of other LED lamps
2) The internal connecting lead of the LED lamp is disconnected, causing no current to pass through the LED, which will affect the normal operation of other LED lamps.
The static electricity of human body will also cause great damage to LED. The LED should wear anti-static clothing and be equipped with a static electricity ring. The static electricity ring should be well grounded. There is a kind of static electricity ring that does not need to be grounded. It is not recommended to use this type of product. If the staff violates the operating rules, they should receive corresponding warning education and also play the role of informing others. The amount of static electricity carried by the human body is related to the different fabrics and clothes people wear and their physical fitness. In autumn and winter, when we take off clothes at night, it is easy to see the discharge between clothes. The voltage of this static electricity discharge is 3000 volts.
Some enterprises use manual welding, using a 40 watt ordinary soldering iron. The welding temperature cannot be controlled. The soldering iron temperature is above 300-400 ℃. Excessive welding temperature will also cause a dead light. The expansion coefficient of LED leads at high temperatures is several times higher than the expansion coefficient at about 150 ℃. The internal gold wire solder joints will be pulled apart due to excessive thermal expansion and cold contraction, causing a dead light phenomenon.
Prevent damage
The reason why LED has a long life is that compared with a more suitable working environment, there are two main causes of LED lighting damage: one is over-voltage shock, which means that the current applied on the LED exceeds the maximum rated current in the LED technical data manual, including over-voltage induced over-voltage shock; The other is overheating damage. But how can we prevent LED lighting from being damaged in reality?
First, prevent electric shock and transient overcurrent. Generally, the electric shock is caused by the great transient over-current, and the direct consequence is to damage other parts near the welding line, such as sealing materials.
Secondly, we should do a good job in the heat dissipation system. At present, the relevant technology of LED heat dissipation system in China is not very mature, and excessive heat will directly lead to the damage of the internal components of LED lighting, leading to the failure of LED lighting.