Talking about the waterproofness of LED packaging materials

Due to the diversity of applications and the complexity of the environment, LED power supplies must have good waterproof performance.  How to waterproof them for a long time requires a system solution which is also a problem that plagues many manufacturers and device suppliers.  Not all systems offer a high level of waterproof protection. High water resistance usually requires a completely closed installation, which can cause heat dissipation problems, and system errors caused by overheating may occur. Is there a solution that has the best of both worlds?

Let's first talk about IP. Regarding IP protection level, it consists of two numbers. The first number indicates the level of dust protection and foreign object intrusion (maximum level is 6). The second number indicates that the appliance is moisture-proof. The degree of sealing of the waterproof intrusion (maximum level is 8), the larger the number, the higher the degree of protection. According to different needs, LED power supply can be designed to be different waterproof and dustproof grades such as IP65, IP66 and IP67.

　　(Laboratory waterproof test)

In order to achieve different IP protection levels and design requirements, shell protection, glue sealing protection, compound protection of glue filling and outer casing can be adopted. Due to the aging and cracking of the shell seal and the high cost of mold opening, it is only suitable for LED products with low requirements for waterproof and heat dissipation. The potting compound with excellent waterproof and heat dissipation properties is more suitable for outdoor and high power LED power supplies. Just like the advertisement of a well-known power supply manufacturer, "only the glue can really prevent rain."

　　(Hot Melt Compound filled Waterproof LED Power Supply)

So, what kind of potting glue is on the market, which one is more suitable for waterproof LED potting? The author compares three commonly used potting glues (see the table below):

The above three commonly used potting compounds meet the requirements of LED waterproof power supply in waterproof and flame retardant performance. The heat dissipation performance of the Spark CQ18P compound is better, and the temperature range is wider than the Corning 8760. Sealing the LED power supply with a well-sealed potting glue can solve the problem of waterproofing and heat dissipation at the same time.

Finally, the appropriate outer shell structure with potting glue, plus wire seals, can effectively ensure the waterproof effect.