How to Charge Car Audio Capacitor

When using large accessories like an upgraded car stereo, you can often experience a strain on your electrical system.

Therefore, when you feel that other accessories are competing to extract the power they require, or when you see your headlights are significantly dimming, it is time for you to get a capacitor.

Before we begin about how you charge a car audio capacitor, it is crucial first to understand the basic idea.

A car audio capacitor is a non-powered device that stores electrical power temporarily. It comprises two electrical conductors (metallic plates) and a dielectric (non-conductor) separating them.

If a capacitor is connected to the power source, the non-conductor stops the voltage flow between the conductors. A static electro field is made between the plates, causing a build-up of charge. This current rapidly discharges when the capacitor is connected to an external circuit.

There are three kinds of car audio capacitors:

• Electrolytic
• Carbon
• Hybrid

Moreover, every capacitor has a particular capacitance (the maximum amount of energy a capacitor can store).

An electrolytic capacitor fast charge rate but contains a slightly low amount of power. On the other hand, a carbon capacitor holds more power but takes longer to charge. A hybrid capacitor is a combination of carbon and an electrolytic capacitor.

A capacitor is normally installed near the amplifier to increase the efficiency of its performance. This position ensures that the voltage drop is reduced so that the entire electrical system performs normally.

A capacitor charges and discharges continuously. For a capacitor to charge, it must be positioned in a completed circuit which must involve a power source, a pathway, and a load. If the load is not included, the current will flow through a circuit, and the capacitor will not be charged.

In addition, there is a general rule that when charging a capacitor, connect its positive terminal to the positive terminal of the car battery and add a resistor between both terminals.

A resistor adds a load to the circuit to ensure the capacitor can be charged. Next, connect the capacitor’s negative terminal to the ground chassis, but not in a similar place with the amplifier.

Also, a capacitor can be charged to the maximum battery voltage level. For instance, a normal 12v battery will charge the capacitor to not more than 12V, and it doesn’t matter whether your capacitor is 1F OR 18F. In most car sound systems, capacitors between 2F and 5F will be enough.

Having used and tested I recommend 3 of the best car audio capacitors below.

1. 5.0 Farad Digital Power Capacitor
2. Planet Audio PC20F 20 Farad Car Capacitor
3. Belva Professional Grade 1 Farad Capacitor

Why do you need a capacitor for your car’s audio system?

1. It stabilizes the voltage of the amplifier – car audio systems that have large wattage or several amplifiers require large currents from the car’s electrical system. According to the songs being played, the amplifiers may require short energy bursts, mainly during transient peaks. When you try to extract this current directly from the electrical system, a noticeable drop voltage is popularly known as voltage sag. This sag depends on the resistance of the wire connecting the battery and the amp. Therefore, a capacitor works as a standby to discharge and provide additional energy when the amplifier uses more current from the electrical system than the system can handle.

2. It helps the amplifier to run cooler and more efficiently. If a capacitor steps into power, it helps the amplifier that was about to strain for power remain cooler for long hours. In addition, the amplifier works more efficiently and gives its best to the sound system.

3. It keeps your headlights lit  – When car headlights dim, it is a sign that your power is reducing. Therefore, because a capacitor prevents the amplifier from extracting large amounts of power from the electrical system, you will have minimal situations of car light dimming. This allows you to blast your subwoofers all day and night long without worrying about the lights.

4. It hinders your music from weakening and flattening when playing heavy bass. Because the amplifier has support to produce power consistently, there is reduced sound distortion. Therefore, this property outlines why capacitors are related to improved transient response. They help the amplifier present better output even during high bass.

What is required to charge a capacitor?

There are a few main items that are crucial when connecting and charging a capacitor:

• Capacitor
• A power wire is similar in size to the one for the rest audio system.
• Wire strippers/ crimpers
• A memory saver
• Pliers

How to Charge car audio system capacitor 

1. Charging with a resistor

New capacitors are packages with a charging tool that is a simple plate with a resistor and four wires.

Two of the wires you have, connect to the positive terminal and negative terminals to the capacitor. Connect another positive wire to the battery’s positive terminal and a second negative wire ground the wire to the car’s base.

Moreover, it is crucial to note that you cannot connect the negative terminal to the audio system’s ground.

Steps:

1. Park your car on flat ground and use the parking brake.
2. Plugin the memory saver.
3. Unplug the ground wire from the battery. Begin with the negative battery cable because you might create a short when you touch the car if you begin with the positive wire.
4. Get the wire you want to use for the positive connection. Make sure there is no fuse on that wire, else it will be blown when you close the circuit.
5. Add connectors to the wires.
6. Connect the capacitor to the sound system. When the capacitor is connected, install the capacitor to the vehicle.
7. Connect the negative terminal of the capacitor to the ground. Ensure that you apply a different point on the base than the existing amplifier’s connection.

After following these steps, the capacitor begins to charge, and after several minutes, it will be ready to start supporting the sound system.

1. Charging a capacitor without a resistor

Like earlier mentioned, if you don’t have a resistor to complete the charging circuit, you can still charge the capacitor with a lightbulb.

To do this, you need extra items:

• 12V light bulb
• Light bulb socket

When you gather all the elements, follow the following steps:

1. Position the capacitor near the battery.
2. Connect the capacitor’s negative terminal to the car’s base.
3. Using alligator clips to hold the test light bulb between the battery’s positive terminal and the capacitor’s positive terminal. After that, hold the test light for a few minutes.
4. Turn off the light bulb once the capacitor is charged.

How long does a capacitor take to charge?

A car owner with a busy schedule would like to know when a capacitor will take to charge.

The time taken to charge a capacitor will depend on the size of the capacitor. It will take less than 5 minutes for the capacitor to charge on average fully.

When comparing the time needed to charge a battery with the time needed to charge a capacitor, a capacitor charges faster.

Can you tell if the capacitor is fully charged?

Are you worried that the capacitor is not fully charged?

To check if a capacitor is fully charged, look at the current value at its voltmeter screen.

However, there are multiple ways of telling if a capacitor is charged when there is no digital display:

• Use a voltmeter.
• Use an analog multimeter.

In addition, it is vital to note that when the capacitor is fully charged and ready to be mounted in the car, it should have a voltage above 13V.

Also, when using an external multimeter or voltmeter to determine the capacitor’s charging level, you must connect the red positive terminal of the multimeter to the positive capacitor terminal and the negative one to the negative terminal. The number displayed on the screen will be the exact voltage of the capacitor.

How many times can you charge a capacitor?

Because of mechanical factors caused by discharges, the components of capacitors, mainly those of high energy storage, happen to reduce with time.

Therefore, the capacitors have a threshold on the charging cycles. However, electrolytic capacitors can withstand a large number of charging cycles compared to others.

What happens when the audio capacitor is not charging?

The capacitor may not charge if it is not a complete circuit. A circuit like that must have a source of power, load, and path for the current to go through.

Remember that a circuit load may either include a resistor or a test light bulb.

And lastly, if your capacitor is damaged, the best thing is to replace it.

Conclusion

To sum, no one wants to keep running to replace another car accessory now and the. However, some vital components in your vehicle could be faulty if the battery focuses on operating the audio system.

For example, the alternator or the battery could be faulty. Therefore, a charged capacitor takes the audio system’s duty as the battery powers all the other devices in the vehicle, and the alternator starts the engine.

Nevertheless, it is crucial to be watchful when handling capacitors. Large capacitors can be harmful, especially when in short. Also, remember to discharge a capacitor before discarding it to the trash as it may start a fire.