Here at Eio, we want to make electronics accessible to all people, experts and beginners alike. We resist assuming our customers will possess or pursue a thorough understanding of electronics, which requires us to provide explanations of electronic equipment in easy to understand, non-technical language. So today’s post is an effort to give a non-technical explanation of capacitors.
What is a capacitor? What does it do?
According to Wikipedia, a capacitor is an electrical component used to store energy by means of an electrostatic field. Capacitors have at least two electrical conductors separated by an insulator, the dielectric (see Fig. 1).
The conductors are connected to terminals so that voltage can be applied across the conductors.
When voltage is applied across the conductors, an electrostatic field develops along the insulator resulting in a positive charge to collect on one terminal and a negative charge on the other. The electrostatic field is what actually stores the energy by the pulling and pushing forces of the positive and negative charges, similar to how charges within protons, neutrons, and electrons hold atoms together.
What are capacitors used for?
Capacitors are used in the following areas:
- Energy sotrage – they can store electric energy and be used like temporary batteries.
- Pulsed power and weapons – they are used to supply huge pulses of current, such as detonators.
- Power conditioning – are used as reserves for some power sources.
- Suppression and coupling – used as noise filters and snubbers.
- Motor starters – starting capacitors are capable of starting rotational motions in many motors.
- Signal processing – used for tuned circuits to read particular frequencies.
- Sensing – senses changes in the capacitance structure.
If you’re an inventor at heart, here are some links to fantastic DIY capacitor projects.
Check out a popular capacitor product at Eio: