1, the lamp string to see the solder joint

The regular LED lamp string production of LED lamp string is produced by the SMT patch process, using solder paste and reflow welding process. Therefore, the solder joint on the string of LED lights is relatively smooth, and the amount of solder is not much, and the solder joint is in an arc shape, extending from the FPC pad to the LED electrode. The amount of solder joint of the string LED lamp is uneven, and more dots cover the welding feet. At the same time, there will be different degrees of tin tips, which is a typical phenomenon of manual welding.

2, light string to see FPC quality

FPC is divided into two kinds of copper and calendered copper, the copper foil of the copper plate is protruding, and the three-phase plug lamp can be seen from the connection of the welding pad and FPC. The rolled copper is closely connected with the FPC, and can be bent arbitrarily without the phenomenon of pad falling off. If the copper plate of the three-level plug is bent too much, the pad will fall off, and the temperature will also cause the pad to fall off during maintenance.

3, look at the cleanliness of the LED light wire surface

If the LED lights produced by the SMT process are strung, the cleanliness of the surface is very good, and the three-phase plug can not see any impurities and stains. However, if the shanzhai version of the LED lamp string produced by the hand welding process is used, the surface will remain stains and cleaning traces no matter how it is cleaned, and the flux and tin residue will remain on the surface of the FPC.

4, light string to see the packaging

The regular LED light string will be packed with anti-static coil tray, the three-phase plug is generally 5 meters in a roll or 10 meters in a roll, and then the outside is sealed with an anti-static, moisture-proof bag. And the copycat version of the LED light string due to cost savings, and the use of recycling coil, no anti-static, moisture-proof packaging bag, carefully look at the coil, you can see the appearance of the label to clear the marks and scratches left.

5, light string to see the label

Regular LED light string packaging bags and coil trays will have printed labels, lights string rather than printed labels. The label of the cottage version is printed, and the specifications and parameters are not uniform.

6. String the lights to see the accessories

The regular LED light string will be attached in the packaging box instructions and light string specifications, three-phase plugs will also be equipped with LED light string connector or cassette; The shanzhai version of the LED light string packing box does not have these accessories, because some manufacturers can save the three-phase plug after all.