4 Facts You Should Know About AC Capacitors

AC capacitors are used in a variety of home appliances and electronic devices. In the contemporary world, homes have become complex, offering several options for entertainment as well as comfort. Since the benefits of hardware repairs cannot be overlooked, you should know about the four essential facts that every homeowner must know about AC capacitors.

First, let us understand the function of the device.

What Is the Function of an AC Capacitor?

AC capacitors are an important part of the air conditioner because they help to regulate the amount of current that flows through the system. The function of an AC capacitor is to recharge the condenser unit after it releases hot air into the environment outside.

This device is also responsible for the stability of the voltage to ensure a smooth, continual flow of current. It can also act as a brake for electromagnetic surges and transients. A capacitor is a device that has an electric charge that can be stored or dissipated.

Facts You Should Know About Air Conditioner Capacitors

Capacitors Don’t Boost the Voltage

Air conditioner capacitors provide the ability to store power, which is done by charging them with high voltage. This might lead you to believe that they will boost your voltage, but in fact, they simply even it out. All air conditioner capacitors utilize a single polarity of positive that’s connected on one side and negative on the other side. Connecting the two sides neutralizes the voltage and does not raise or lower it.

Currently Does Not Flow Through the Capacitor, It Flows in and Out of It

The principle of operation behind air conditioner capacitors is that of a current flow in and out of a polarized capacitor. The amount of current flowing out or into the capacitor determines whether it’s absorbing or releasing power.

While this should be fairly obvious, it’s important to point out that it is only the current (in and out of the capacitor) that causes the capacitor to heat up. The current does not flow through the capacitor itself, but it only uses the capacitor like a resistor with a very high value. Because we are dealing with such large values of current and voltage in an AC circuit, the reactive effects of capacitors are often negligible.

The Higher the Capacitance, the Higher the Current on the Start Winding

There are some things that should be known about the development of capacitors. For instance, the older air conditioning system capacitors were made up of a large number of small individual capacitors that are connected in parallel to increase the capacitance. Newer capacitors are made of fewer, larger units called electrolytic capacitors which makes them much less expensive than the older equivalent.

These electrolytic capacitors can be up to half the size of a standard automotive capacitor and cost about half as much. To get a higher capacity, you have to get a high voltage unit since the voltage is directly related to capacity.

The higher the voltage, the more current the start winding will require. This is an important consideration in older equipment like window units where starting current is usually limited by the wire size in the start winding.

The Voltage Rating Is What it Can Handle, Not What It Will Produce

Even though the nominal voltage of an AC capacitor will be stamped or written on the side of the unit, it is not a direct indicator of what the unit will supply at any given point. Numerous specialists believe they should supplant a 370v capacitor with a 370v capacitor.

The voltage rating shows the “not to surpass” rating, which implies you can supplant a 370v with a 440v yet you can’t supplant a 440v with a 370v. This misinterpretation is regular to the point that numerous capacitor producers started stamping 440v capacitors with 370/440v just to wipe out uncertainty.

A Capacitor Can Be Tested While the Unit Is Running

A licensed HVAC professional will multiply the taken measurement of the current (amps) of the motor start winding coming off the capacitor by 2652 (on 60hz power 3183 on 50 Hz power), then that number will be divided by the voltage measured across the capacitor.

The purpose of this article was to shed light on some things that you should know about AC capacitors. Like most of those reading this piece, you have probably never given much thought to capacitors. If we are not using them to store electricity then they remain in the background noise of our lives. But, while we don’t notice capacitors, they do all the heavy lifting.