How Long Will A Deep Cycle Battery Run A Car Stereo
A deep cycle battery is designed to provide a long, steady discharge of electricity over a period of time. They are often used in applications such as RVs, golf carts, and marine vessels where they are regularly called upon to power electrical systems for extended periods of time. But how long will a deep cycle battery actually run a car stereo?
To answer this question, we need to first understand how car stereos work. Most car stereos today are powered by 12-volt DC batteries. These batteries store electrical energy in chemical form and then release it as direct current when connected to an external circuit.
The amount of electricity that can be stored in a battery is measured in amp hours . So, how long will a deep cycle battery run a car stereo? It depends on the capacity of the battery and the power requirements of the stereo system.
A typical 12-volt, 100 Ah deep cycle battery can provide 1 Amp of current for 100 hours or 10 Amps for 10 hours. If your car stereo system draws 20 Watts of power , then that same 100 Ah deep cycle battery would theoretically be able to run your stereo continuously for 5.8 hours . However, most experts recommend that you dont discharge a lead acid battery below 50% to avoid damaging it, so in reality you would only be able to get 2.9 hours of continuous use out from your deep cycle battery before needing to recharge it again.
Attach The Battery Box
Before starting your extra battery installation, park your car in a safe place such as a garage, and turn it off.
Youre installing the extra battery for the car audio system, so you want to place it in the trunk close to the amplifiers. This location makes the wiring between the extra battery and the audio system much easier.
- Attach the drill bit to the drill motor and drill holes through the installing plates of the battery box into the trunks floor.
- Using the parts that come with a battery box, attach the battery box to the trunk floor by putting a bolt-on on each installing plate.
- Tighten the attachment using a wrench to prevent the battery from moving while driving.
- Depending on the battery box or tray you are using, you might need to drill holes to make way for connection cords.
It is advisable to be extra careful when drilling to avoid damaging the fuel tank or other components. Fit your extra battery into the box once the battery box is in place.
Reserve Capacity Of The Battery
Reserve capacity refers to the number of minutes that a fully charged battery is able to sustain a 25 amp load until it gets discharged to 10.5V. This reserve capacity directly affects the operating time. Therefore, higher reserve capacity increases the time that you can listen to a high-performance audio system while the engine is off.
Keep in mind: Above amps and voltage values should be measured at 80°F.
Second Battery or Higher Reserve Capacity?
Buying a new battery that has a higher reserve capacity is one way to solve the lack of power issue on your car. All you need to do is replace the stock battery with a new battery that has a larger reserve capacity.
However, first, check the size of the new battery. It might not fit into the old battery space. If everything works smoothly, you wont need a second car audio battery.
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Installing New Matched Batteries
A common way to add an extra battery to your car is to replace the current battery with two matched batteries. Both replacement batteries must belong to the same age, group, and brand to get excellent performance.
Try the usual method of placing one battery precisely where the old battery was and wiring the second battery in parallel. By parallel, this means you will connect the negative terminal on one battery to the second batterys negative terminal. Do the same for the positive terminals.
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Do Big Stereos Need Extra Batteries
Customers often ask us if they need to add an extra battery or two when installing a large car audio system that includes multiple amps, speakers, and subwoofers? Deciding to add an extra battery is dictated by the system and how it will be used, and an alternator upgrade may be a more important consideration.
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Is The Wiring For My Car Audio Amplifier Or Speaker Big Enough
August 12, 2022 By Dave MacKinnon
Somewhere around ninth grade, most high school students in North America learn about Ohms law in science class. Despite repeated efforts and claims to debunk the laws of physics, Ohms law remains a constant that car audio enthusiasts and professionals deal with every day. On a related subject, I see questions about speaker and amplifier wire sizing all the time. To help people get an honest answer to their questions about wire size, lets step away from our usual educational path for a hands-on method of checking your existing audio system wiring to determine whether it needs to be upgraded.
Can I Connect Two Separate Batteries In Parallel To Keep My Car Powered
You can connect two batteries If you have the same battery voltage. For example, you have a 12 volt battery, you can connect two batteries in series to produce 24 volts. It is not recommended to make a series connection of two batteries with different voltages. Otherwise, you may damage both batteries. To get more power, buy a new battery for your car or use a car charger.
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How Can I Install An Extra Battery For Car Audio
Before starting, you need to know where to put the additional battery, and the best place used often is the trunk near the amplifier.
Installation may vary depending on the exact battery type, but for typical cases, I listed general rules below:
- Connect the positive terminal of the extra battery to one of the side terminals of the battery isolator, and then connect the negative terminal to the negative terminal of the primary battery.
- Connect the positive terminal of the primary battery to the other side terminal of the battery isolator and then connect the alternator to the central terminal of the battery isolator.
- Connect the positive terminal of the extra battery to the amplifiers fuse and then connect the fuse to the positive terminal of the amplifier.
- Connect the negative terminal of the amplifier to the negative terminal of the extra battery.
Although it is not a must, you can ground the extra battery by connecting its negative terminal to the car chassis.
Before installing the extra battery, equip yourself with the following:
- A drill motor and a drill bit
Watt Rms Mtx Jackhammer Subwoofer
Most stock electrical systems use alternators that are between 60 and 120 amps. Even if you add batteries your stock alternator will still limit the amount of current that can be sent to the batteries. Although upgrading your alternator may be more expensive, in the long run your system and vehicle’s electrical system will perform much better than just adding a battery.
Some very high power audio installations such as the MTX Jackhammer Dodge Ram install shown, use multiple alternators to acheive adequate amperage . The Jackhammer is rated at 4000W RMS!
Be sure to evaluate the cable between the alternator and battery to ensure it can handle the increased amperage too. Car manufacturers size this cable to act as limiting protection for the alternator in case of excessive current draw from a bad battery cell. Upgrading the ground wire is also needed if the alternator is upgraded to a higher output. If you stay with the factory alternator avoid changing the wires as well.
Consult your car audio installer or call 1-800-CALL-MTX for advice on current draw from your amplifier to see what options would work best for your system.
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Second Batteries For High
The other way to add extra reserve battery capacity is to actually add a second battery. In this case, youre typically going to get the best results by ditching your existing battery and putting in two matched batteries. The batteries should be the exact same brand, group, and age.
The new batteries dont have to be the same group as the original battery, but they should be the same group and same production date as each other. This is essentially just to ensure that one battery doesnt end up getting overworked and that neither battery tries to pull juice out of the other when the car is off, which can lead to a shortened life expectancy.
If youre installing new matched batteries, one should go right where the original battery was, and the other needs to be wired in parallel. You can install the second battery in the passenger compartment or the trunk, although you need to take precautions if you install it in the passenger compartment, and it’s a good idea to use a battery box or some other kind of protection even if it goes in the trunk.
When you wire the batteries together, it’s essential to wire them in parallel. This means you connect the negative terminal on one battery to the negative on the other and also connect the positive terminals together.
It’s also important to use heavy gauge battery cable, and the positive cable should have an in-line fuse. For extra protection, consider installing a fuse at both the original battery and the second battery.
Power Distribution For Large Audio Amplifiers
If your audio system current draw exceeds the output current rating of the alternator, then your dashboard, or headlights, may dim especially when loud bass notes hit. Not a good thing. Also, this power choke can affect the performance of your sound system leading to amplifier overheating and even shutdown, which is not a good result. You can calculate the amperage draw of your system using Ohm’s law. In this case you can use the formula I = P / E .
Adding a battery is the quick solution to this problem, but may not be the best solution. For example, a 2000W RMS amplifier will potentially draw up to 240 amps of current depending on the design and efficiency of the amplifier. Even though the normal operation of the amp will probably run less than that on average, even half of that, 120 amps, is more than most vehicle electrical systems supply to run the entire vehicle.
Let’s look at a specific example. If you have a mono block and a 4-channel amplifier that each are rated at and outputting 500-watts RMS power, you have a total of 1000-watts. Your alternator is rated at 14.4 volts, so the resulting calculation for current would be I = 1000/14.4. The result is 69.44 amps.
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How To Install A Second Battery For Your Cars Audio System
We do love to travel a long distance. By car, we would have covered a far distance with our family. Of course, long journey aches without any fun. However, we have a healer to relieve us from those aching.
Yeah, it is the music. Music is the universal language of mankind Henry Wordsworth Longfellow. It is the only remedy for your ache in your soul. To hear a good music we need some equipment. Speakers alone will help us to hear the divine music.
A car with speakers along with music can make anyone travel any distance. Now, we are going to see how to install a second battery for the car.
How To Install A Second Car Audio Battery In Your Vehicle
How do you run 3 car batteries?
A car battery can typically be run from a single 12 volt battery. If you have three 12 volt batteries, you can connect them in series to get 24 volts.
How do you hook up a second battery for car audio diagram?
There are a few ways to do this. One way is to use an adapter that will allow you to plug in a second battery into the car audio system. Another way is to buy a second battery for your car audio system.
How do you hook up two batteries to one alternator?
There are a few ways to do this. One way is to use a pigtail connector. Another way is to use a Y-connector.
Do I need a bigger alternator for two batteries?
The answer to this question depends on the vehicle and the batteries you are using. If your vehicle is equipped with a charging system that can handle two batteries, then a larger alternator may be unnecessary. However, if your vehicle is not equipped with a charging system that can handle two batteries, then you will need a larger alternator in order to provide enough power for both batteries.
How do you wire 3 batteries in parallel?
The easiest way to wire three batteries in parallel is to connect the + terminals of two batteries together and connect the terminals of the third battery to the remaining + terminal on one of the other two batteries.
How many 12 volt batteries can you run in parallel?Will adding a second battery help my audio system?When should you add a second battery for car audio?
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How To Determine Whether Your Wiring Is Large Enough
The ANSI/CTA-2005 Mobile Electronics Cabling standard allows for a maximum voltage drop of 0.25 volt along any length of cable. Since weve included the fuse, chassis resistance and return path, our 0.99-volt calculated voltage drop value is high. Lets calculate what voltage drops across the 15 feet of 4 AWG power wire: 100 amps multiplied by 0.0040236 ohm is 0.40236 volt. This is also a little high. Ideally, you need 15 feet of 2 AWG wire to feed an amplifier capable of consuming 100 amps of current. The voltage drop would be 0.25146 volt along a 15-foot length of 2 AWG wire when 100 amps of current pass through it.
Since most wiring sold for car audio systems is undersized relative to the full AWG specification or contains tin and aluminum, its nearly impossible to know its resistance per meter or foot. Ultimately, all we want to know is how much voltage is being wasted, which is very easy to measure. Ill show you how.
Youll need a digital voltmeter. It doesnt have to be a fancy Fluke or B& K Precision model you can use a $7 Harbor Freight meter with reasonable success. Higher-quality meters will read faster and more accurately, so you might not want the least expensive unit you can find.
What To Do If You Measure Too Much Voltage Drop
The voltage drop test thats outlined above can be used for any electrical system where youre concerned about a bad connection or undersized conductor. It works on wire from a remote-mounted battery kit or wiring to a high-power ignition module or cooling fan. If you think a fuse or circuit breaker is bad, measure the voltage across it.
If you measure too much voltage across a conductor, the easiest solution is to have your installer upgrade the wire to something more suitable for the systems current consumption needs. You can also add a second power wire run, which should cut the voltage drop in half if you use the same conductors.
If the voltage drop problem is on the ground side, the vehicle chassis is likely the issue. I recommend having your installer run a parallel ground from the rear ground point to the negative battery terminal. This extra ground path is especially critical on new vehicles that use adhesives instead of spot welds to attach body panels together.
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It May Not Help To Install Another Battery For Your Stereo
- Shoreline Community College
Unless you want to listen to music with your engine off, adding a dedicated car audio battery isn’t going to do you any goodand it may actually hurt. That might seem counterintuitive, but the reasoning is simple.
The battery in your car is there to serve one purpose: to provide enough amperage to start the engine. After the engine is running, and the alternator is spinning, the battery acts as a load. If you add a second battery, it’s going to act as a second load when the engine is running because the alternator keeps both batteries charged.
Second Car Audio Battery For High
The other way to add extra battery life is to actually add two batteries. In this case, youre typically going to get the best results by ditching your existing battery and replacing it with two batteries. The batteries should be identical in brand, group, and age.
What batteries should you use? It doesnt really matter, as long as they are from the same production batch. You have to make sure that one battery doesnt work too hard and the other doesnt try to steal its energy when the car is off.
When adding a new battery, its important to follow the wiring diagram to avoid problems. The new battery should go in the same place as the old one. The other wire must be connected parallel with the original one.
The second car battery can be installed in the trunk or the passenger compartment. If you install it in the passenger compartment, take precautions to limit the chance of a fire. Its best to use a battery box or other protective device, even if it goes in the trunk.
If you connect your batteries in parallel, youll have more power. This means youll link the negative terminal of one battery to the negative terminal on the other battery, and also connect the positive terminals together.
Its important that you use heavy-gauge cables and fuse the positive cable. To provide extra protection, consider fusing the positive cable at both the original battery and the second battery.
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