For metallized film capacitors, a metal film is attached on the surface of the polyester film using the vapor deposition method. Therefore, the metal film becomes the electrode instead of metal foil. Because the thickness of the metalized film layer is much thinner than that of the metal foil, the volume after winding is also smaller than that of the metal foil capacitor. In recent years, metal film capacitors have been favored because this type of capacitor has excellent performance. In this article we will talk about the advantages and disadvantages of metal film capacitors.
The “self-healing” feature is a very important advantage of metallized film capacitors. The so-called self-healing characteristic is that if the thin film dielectric has defects at a certain point, a breakdown short-circuit will occur under the action of overvoltage. The metallization layer at the breakdown point can be melted and evaporated instantaneously under the action of the arc to form a small metal-free zone, so that the two pole pieces of the capacitor are insulated from each other again and can still continue to work, which will greatly improve the reliability of the capacitor.
The disadvantage of metallized film capacitors is their poor ability to withstand large currents. This is because the metallized film layer is much thinner than metal foil, and the ability to carry large currents is weaker. In order to improve the shortcomings of metallized film capacitors, there are currently improved high-current metallized film capacitor products in the manufacturing process. The main ways to improve are: use double-sided metallized films as electrodes; increase the thickness of the metallized coating; improved metal welding process to reduce contact resistance.
The above content is the advantages and disadvantages of metallized film capacitors. Good metallized film capacitors can reduce unnecessary troubles. JYH HSU(JEC) Electronics Ltd (or Dongguan Zhixu Electronic Co., Ltd.) has engaged in the electronic component industry for many years, and our technical engineers can help you solve related problems. When purchasing varistors, you need to find out whether the products come from regular manufacturers. A good varistor manufacturer can reduce many unnecessary troubles.
JEC has over 30 years of manufacturing experience in the electronic components industry. If you have technical questions or need samples, please contact us.
Post time: May-20-2022