[Explanation of the Causes of Capacitor Failure] A Case Where Sound Came from a Film Capacitor

If the sound level exceeds the acceptable range, please use the "soundproofing product" with a short body type!

Here is a case where a sound like "zi" or "pi" was heard from a film capacitor when the power was turned on. Film capacitors have a structure that consists of extremely thin plastic film rolled up. While the electrodes at both ends of the element are fixed, the body part is not fixed, making it prone to vibration. When voltage is applied to the capacitor, the Coulomb force acting between the electrodes can cause the dielectric plastic film to vibrate mechanically, resulting in a humming sound. In particular, if there is distortion in the power supply voltage or if the waveform contains harmonic components, the sound level can be high. [Countermeasures] ■ Continuous vibration sound - It is not a malfunction; it does not affect electrical characteristics or reliability. - Capacitors with long cylindrical or flat-shaped elements tend to produce louder sounds. ■ If the sound level exceeds the acceptable range or if there are sporadic popping sounds - Please use a "sound-dampening product" with a short cylindrical shape. *For more details, please refer to the PDF document or feel free to contact us.

Capacitor