What Is a Capacitor and What Does it do?

A capacitor is a passive component of an electrical circuit. It has two terminals and is used to store energy in an electrical field. You could think of a capacitor almost like a cloud, in that capacitor stores energy like cloud stores water. Capacitors are used in a lot of electrical circuits that are found around your home. Unlike resistors, capacitors do not dissipate energy.

CHINT capacitor is necessary for several reasons. No matter what type of electrical circuit you develop, its design may often include a capacitor. The primary reason for using a capacitor is that some devices require a large surge of energy when they’re first starting up. For example, if you’re using your television, it needs a lot of energy to be immediately available when you first turn it on. The same goes for many other domestic devices.

A capacitor stores energy in your circuit. It stores enough energy so that when you click the button to start any device that uses power from your electrical circuit, it can start operating immediately and do so in a smooth, seemingly effortless manner. If the capacitor wasn’t there, the circuit might not perform its function, because it would not have enough energy provided by the AC power source at the beginning.

What Does a Capacitor Do?

A capacitor stores energy inside your electric circuit. It keeps this energy ready for when a tool in the circuit is being started. Ordinarily, the electrical circuit that delivers energy to your tool would not be able to deliver as much power as the device needs all at once in the beginning. The capacitor solves that problem by ensuring your tool can get the extra power that it needs at the start. 

How to Test a Capacitor?

You can test a capacitor by using several of the devices. A multimeter is one of the most popular devices that is used to test a capacitor. You can also get several other measurement devices that are helpful for testing other electrical components of your electric circuit.

To test a capacitor, by using a multimeter, ensure that you put the device to read at its highest Ohms range. This is usually above 10K Ohms. You can start at 1,000 Ohms as well. Touch the leads of the multimeter to the corresponding terminals on your capacitor. That is, ensure that you place red to positive and black to negative.

You should see the meter measure a low resistance and then that should build slowly towards infinity. If it does that, it means the capacitor is working properly. You’ll need to keep the meter connected to the leads of the capacitor for at least a few seconds in order to see this happen. Don’t just touch the meter’s leads to the capacitor for an instant or you won’t observe the change.

How to Tell If a Capacitor Is Bad?

A capacitor can be tested with an Ohm meter or a multimeter to tell if it has stopped working properly. It should show low resistance initially and then, the resistance should increase towards infinity. That is, the resistance should start off low and then keep getting bigger and bigger until it approaches an extremely large number.

If a capacitor is short, it won’t show much resistance. The value of the resistance that is measured on the Ohm meter will be very small. If a capacitor is open, it won’t show any movement at all on the screen of your Ohm meter. That is, it won’t show a deflection when you use the Ohm meter on it. Either of these states means that the capacitor is not functioning as it should and will not be of benefit to your electric circuit when it’s in an electrical circuit. You’ll need to have the capacitor changed in that case, for your electric circuit to work well.

Bad capacitors leak electricity like sieves and they are never supposed to do that. After all, if your electric circuit is designed to use a capacitor that can hold a specific amount of charge and your capacitor leaks, it won’t be able to supply that quantity of charge to your circuit when you need the circuit to perform the function that it is designed for.

You don’t always need to use an Ohm meter or another measurement device like a multimeter to tell if a capacitor is bad. Sometimes you can just check the outside of the capacitor and you’ll notice that it has a swollen or domed top. It’s not supposed to be like that. If the capacitor in your electric circuit is bad, it may be leaking electrolyte and this would be seen as stains or a brown crust that is similar to a coffee stain around the top.


A capacitor is used to store charge in your electric circuit. The capacitor stores enough energy so that your electric circuit can work smoothly at all times. When a capacitor works as it should, your electric circuit is less likely to produce sparks or cause a disruption in the delivery of electrical power.