Precautions for power adapter potting glue?adapter power

　　This is simple to say. It may be that the customer requested glue, or it may be that someone else is looking for glue filling. To be sure, there are several major purposes and requirements for potting glue:

　　1. Waterproof, the potting glue tightly wraps the electrical part of the power adapter and completely isolates it from the outside world; any water, moisture, acid, alkali and salt cannot reach the circuit components, which can improve the waterproof, moisture-proof and anti-corrosion ability. So the glue you choose should have good fluidity. If the fluidity is not good, how can it be deeply penetrated and completely sealed; and the adhesive strength must be possessed, otherwise it will be useless if the components are separated from the components for a long time after potting. Life performance is also affected.

　　2. Thermal conductivity, the power adapter is a power product, which is to convert, control, and output energy to the outside. When the adapter is working, it will generate heat. Like switch tubes, transformers, electrolytic capacitors, inductors, etc., which are not heat-generating devices and are heat-resistant devices. What to do, it must be conducted as soon as possible and as much as possible. Therefore, the glue must have good thermal conductivity. It can be said that the higher the thermal conductivity of the glue, the better. The electrolytic capacitor in the power supply has a life span of about half when the temperature rises by ten degrees, but you can’t add a heat sink to it; when the temperature of the transformer and inductance is high, many parameters change and the overall design becomes more difficult, and you are not good to add it to it. A heat sink.

　　The entire waterproof power supply needs to be sealed, and the thermal conductivity of air is very low, mainly relying on convection and radiation. But convection is impossible, and the components are stuffed in the box.

　　Therefore, pouring the glue with good thermal conductivity can be equivalent to putting each component outside to dissipate heat, which not only improves the life span but also simplifies the design.

　　3. Dielectric strength, this is easy to handle. Basically all glues are non-conductive, but it should be noted that the incomplete curing reaction of epoxy-based AB glues may cause a little partial conductivity. It is hard to say that sand is mixed in it to save money. The first is whether your sand has been processed by dehydration treatment, or whether there are other elements in your sand that interfere with curing; whether the ratio of AB agent is reasonable, whether the mixture is sufficiently uniform, and whether other conditions are available.

　　4. Environmental protection requirements, adapters generally have been certified. It depends on whether the products provided are consistent with the certified ones, and the price difference between environmentally friendly and non-environmentally friendly materials is still a lot.

　　5. The flame retardant requirements generally depend on the flame retardant test in UL. Generally, 94-V0 or more is required.

　　6. There are so many other parameters, you have to fill it up and try it yourself. The main thing is that your supplier must be constant, his supply must be stable, and the process must be stable. Otherwise, the dispersion is too large.

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