Why do film capacitors need wax injection

    The issue of wax impregnation for film capacitors is rather obscure, and I believe many people are unfamiliar with it. I myself only gained some understanding after discussing this with a customer in detail, and I hope this article can provide some experience and knowledge for everyone.

    During a customer conversation, the other party asked, "Does waxing CBB capacitors improve power supply noise? Do you currently offer waxed CBB capacitors?"

    What is wax injection? When the insulation of a component in a film capacitor decreases, it will inevitably generate abnormal heat, increase the internal pressure, and cause the film capacitor shell to deform and expand. The mechanical displacement will break the explosion-proof wire. Since the power supply is connected to the film capacitor element through the explosion-proof plate, disconnecting the explosion-proof plate is equivalent to disconnecting the power supply, thus putting the circuit in an open-circuit state. Its explosion-proof effect depends on the design and installation location of the explosion-proof plate, as well as the sealing performance 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. Internal pressure-type explosion-proof device, ensuring safe and reliable use.

    A: Current metallized products are coated with wax, which provides better moisture resistance and better dimensional control, and has nothing to do with power supply noise.