Polyester Film Capacitors

Polyester film capacitors are a type of capacitor (devices made of one or more pairs of conductors separated by an insulator, used to store an electrical charge), where the polyester film (PET) is used as the insulation material. Compared to other capacitors, polyester has great benefits. They’re a very popular and cheap capacitor making them brilliant use for all applications.


Polyester film capacitors are typically used as general purpose capacitors so can be used in a variety of products. They’re low cost, small and most have a high capacitance value. Typically they’re used for DC (Direct Current) applications or semi-critical circuits. Polyester film capacitors are also not polarized so they could be used for AC (Alternating Current) signal and power usage.

Most polyester film capacitors can be used in harsh environments where they need to withstand heat & moisture and some other characteristics. They make a great used for all applications.

Key characteristics

  • High dielectric (insulation) strength - The polyester dielectric used in these capacitors (Also referred to as PET) offers a high level of insulation

  • Operating temperatures - With the properties of the polyester dielectric our polyester capacitors can work up to temperatures of 125°C making them great use for harsh environments.

  • Tolerance - Many polyester film capacitors have a tolerance of 5% or 10%, but this is adequate for plenty of applications where insulation strength or temperature resistance are of greater concern.

  • Humidity resistance - Polyester film capacitors tend to have a brilliant resistance to moisture so makes them a great use in more harsh environments.