What is the use of wax injection for film capacitors

The issue of thin film capacitors impregnated with wax is relatively obscure. I believe many people are not clear about it. The editor happened to encounter a customer who asked this question and discussed it carefully before understanding it. I hope this article can give you some experience and knowledge.

During a conversation with a customer, the other party asked, "Does wax injection of CBB capacitors improve power supply noise? Are there any CBB capacitors with wax injection currently?"

What is wax injection? When the insulation level of a certain component of the film capacitor decreases, it will inevitably generate abnormal heat, increase the internal pressure, and cause the film capacitor shell to deform and expand, and the mechanical displacement will break the explosion-proof wire.Since the power supply is connected to the film capacitor element through the explosion-proof disk, the explosion-proof disk disconnects the power supply, thus making the circuit open. Its explosion-proof effect depends on the design and installation position of the explosion-proof disk and the sealing of the film capacitor.

Characteristics of wax-impregnated film capacitors: 1. Small size and light weight. 2. Excellent electrical performance, low loss, and good self-healing properties. 3. There is a pressure-type explosion-proof device inside, which is safe and reliable to use.

Answer: Today's metallized products are dipped in wax, which is better at blocking moisture and controlling size, and has nothing to do with power supply noise.