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Capacitors FAQ

What they do, and when to use one


Buck Pomerantz

Buck Pomerantz was born and raised in Philadelphia. His parents bought their first television set when he was born. He figured out how to run it by the time he was two. Besides athletics, his formative interests included electronics, amateur radio, music, and stage crew work. He got his BA in writing from Brown University. Then he joined a rock 'n roll band as their soundman and moved to Charlottesville, Virginia. After that venture failed, he spent time in Boston, New Orleans, and Berkeley. He worked in a music store in Austin manufacturing, installing, repairing, and operating sound systems for recording studios, clubs, and bands. He moved back to Charlottesville, ran a little recording studio and finally joined Crutchfield as a copywriter. He has 2 grown children and 3 grandchildren, but after a good nap he can still rock out.

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Q: What's a capacitor?

A: A capacitor, or cap, is an electronic component that can take up, store, and discharge electrical energy. Because they can do all that quickly, capacitors are used to filter or buffer any sudden changes in a circuit's voltage, smoothing the ensuing signal.

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Q: What's a capacitor used for?

A: In car audio, large outboard capacitors, sometimes called stiffening caps, are used to prevent lights from dimming when loud bass notes play. They accomplish this by supplying the amplifier with a quick jolt of power.

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Q: Even if my lights don't dim, won't a cap still improve my system's low end response and overall sound?

A: Not really. A cap prevents the sound from deteriorating due to under-voltage, but doesn't actually improve the sound. It supports the amplifier by feeding it the power it needs for short bursts. So, while not improving sound quality directly, a cap does make it easier for the amp to perform its best.

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Q: What size cap should I get?

A: The rule of thumb is to put in 1 Farad of capacitance for every 1,000 watts RMS of total system power. But there is no electronic penalty for using larger value caps, and in fact, many see benefits with 2 or 3 Farads per 1,000 watts RMS. The larger the cap, the faster it gets ready for the amp's next big hit.

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Get Everything You Need

Give your subwoofer amp the boost it needs with a capacitor. We also have all the installation hardware you need to get your capacitor and amplifier up and running.

Q: How do I hook up a capacitor?

A: If you don't have the instructions that came with your capacitor, you should know first off that a cap can be dangerous; it can charge and discharge so much power so very quickly that it can weld metal objects, like tools and jewelry, and melt its own insides out. A new cap comes completely discharged, so it's safe. A resistor or wired light bulb usually is included in the package. Wiring the bulb or resister across the cap's terminals allows the capacitor to discharge slowly and safely. The same bulb or resistor, wired differently, also gets used to charge up the cap safely.

As in all car electronic installations, start by disconnecting the ground cable from the car battery. In this installation, also take out the in-line fuse on the amp's power wire next to the battery.

A capacitor should be mounted as close to the sub amp as possible using the shortest wires possible. This is so the extra charge doesn't have far to go to get to the amp quickly. Make sure the cap gets mounted securely and won't become a dangerous flying object in the event of an accident.

A capacitor has two poles: a positive and a negative. They should be clearly marked on the capacitor. The positive connects to the same positive power lead that goes to your sub amp's positive, 12 volt, connection. Use the same gauge wire as the amp uses for its power. This can be accomplished with a distribution block. Or, sometimes, the cap comes with multiple connection terminals that make it easier to wire it into your system. The multiple terminals act just like a distribution block so, for instance, the power wire coming from your battery can connect directly to the cap's positive terminal while a short cable connects from there to the amp's positive power connection. The negative pole of the capacitor connects to your chassis ground, just like the amp. The best practice is to use the same bolt the amp uses for ground. Make sure all the paint is scraped off around where you put the chassis ground and the connections are clean and tight.

Next, you need to charge up your capacitor. If done too quickly — it could "pop," destroy the cap.

If you don't have the original charging/discharging resistor or light, you'll need to get one. An automotive 12-volt test light, the kind with a bulb, not a small LED, will do nicely. Otherwise, you can use a high-wattage, low resistance resistor, available at most electronics parts stores. The exact value doesn't matter, but get one with a value of 10-1,000 ohms along with a rating of 1-20 watts. The lower the resistance, the higher the wattage should be.

Take the test light or resistor and connect it to the two terminals of the amp's in-line fuse holder (where you took the fuse out earlier). Re-connect the car battery's ground cable. The resistor will get hot, or the bulb will light up, while the cap charges. After 10 to 30 minutes, the bulb will fade out, or the resistor will start to cool. Remove the light or resistor carefully — they can get very hot. As you replace the fuse, you may experience a small spark — that's okay, but should remind you of how powerful the electric forces involved are. Your capacitor is now installed.

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Q: My cap has a third terminal. What's that for?

A: Some caps come with a built-in meter that displays the voltage. If a meter were to stay on constantly, it could drain the car's battery. So caps with meters often have a remote turn-on lead connection, just like car amplifiers, so the meter turns off with the system. A thin, 18-ga. or so, wire should run from the cap's turn-on connection to the amplifier's remote turn-on terminal, or any other switched 12 volt power source.

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T-Spec capacitor

T-Spec 3.0-farad capacitor

  • K. Hardy from Calgary, Alberta

    Posted on 4/25/2015 5:15:59 PM

    Can capacitors be mounted on the firewall under the hood?

  • K. Hardy from Calgary, Alberta

    Posted on 4/25/2015 5:30:26 PM

    Does a powered subwoofer also need a capacitor connection?

  • Buck Pomerantz from Crutchfield

    Posted on 4/27/2015 10:01:07 AM

    K, A capacitor can certainly be used with a powered subwoofer. A capacitor should always get mounted as close to the subwoofer's amplifier as possible, never under the hood in the engine compartment.

  • John from New york

    Posted on 4/27/2015 7:43:07 PM

    Can you put one cap on two amplifiers ?

  • Buck Pomerantz from Crutchfield

    Posted on 4/28/2015 10:26:21 AM

    John, A capacitor gets wired with one wire running from its negative terminal to ground and one wire from its positive terminal to the positive 12-volt power line of an amplified system. It does the most good to connect a cap closest to the subwoofer amplifier in a system, but it won't hurt to connect it elsewhere, like at a distribution block.

  • Cory Dzbinski from Oceanside, CA

    Posted on 5/14/2015 2:50:08 AM

    Hey there, good article. I have a question that seems obvious to me but I haven't see it asked or explained anywhere. Won't the cap slowly discharge when it's off? What if you don't drive your car for a couple weeks. Won't the cap be empty and be at risk to "pop" and destroy the cap if it then recharges quickly?

  • Buck Pomerantz from Crutchfield

    Posted on 5/14/2015 9:56:27 AM

    Cory, As long as the vehicle's battery maintains a charge, it will keep the cap charged. If the battery loses its charge or gets disconnected, then the capacitor will lose its charge and need to be re-charged slowly, like it was newly installed.

  • Lee

    Posted on 7/12/2015 9:11:21 PM

    I have had great success with stiffening caps in-line with A/B amps. Will a cap help with a class G amp?

  • Buck Pomerantz from Crutchfield

    Posted on 7/13/2015 4:03:11 PM

    Lee, A capacitor's function is unaffected by the technological Class of an amplifier's internal circuitry.

  • Nick Duval from Canada

    Posted on 7/18/2015 1:14:11 AM

    My capacitor has recently starting making a high pitched screeching noise what could cause this? It doesn't happen all the time, it happens randomly.

  • Buck Pomerantz from Crutchfield

    Posted on 7/20/2015 8:50:02 AM

    Nick, I have never personally heard of such a thing, but it probably is not good. I have seen capacitors fail by springing a leak, developing a hole where internal gases have pushed through the casing. Maybe that's what's happening to your cap.

  • Amanda

    Posted on 7/25/2015 9:58:24 AM

    Hi! I just want to ask if an audio capacitor has fumes? And if it has fumes in it, can it be dangerous to our health? Is there any chance that the fumes will leak? Hope you could reply to my email asap. Thank you!

  • Buck Pomerantz from Crutchfield

    Posted on 7/25/2015 4:52:09 PM

    Amanda, There are no fumes or gas inside capacitors. Capacitors are made of two foil sheets wrapped together with a chemical called a dialectic in between them. Like in a car battery, this substance may contain some acid, but you'd have to rub it in your eyes, roll in it, or eat a bunch before it would do you any harm. That being said, I think it is possible that when a capacitor fails catastrophically the electric charge could vaporize some of the dialectic and release a small puff of gas that if breathed in probably won't be good for you. If you or a friend think you've been exposed to such a thing, I recommend flushing the area out with water, and contacting your doctor for advice.

  • sr5573 from bhubaneswar

    Posted on 7/30/2015 2:13:10 PM

    what is the working principle of a capacitor?

  • Buck Pomerantz from Crutchfield

    Posted on 7/30/2015 4:01:38 PM

    SR, Check out this 5-page article How Capacitors Work. It ought to answer a lot of your questions about capacitors.

  • pelonomi from gaborine

    Posted on 8/4/2015 2:53:05 AM

    hi, amplifier(1200W), subwoofer(1000W), 6x9 speaker (350W), twitter(300W) and capacitor connected between amp and power source, my question is there is disturbing noise when car rev or on drive what could be the cause of that, and most of the time fuse (connecting amp with power source) are blown

  • Buck Pomerantz from Crutchfield

    Posted on 8/4/2015 12:08:25 PM

    Pelonomi, The number one cause of engine noise in a car audio system is a loose or intermittent ground connection. That could also explain the blowing fuses. Carefully check your amplifier's power and ground wiring and correct any faults you may find. Make sure the ground wire makes a clean, tight, and paint-free contact with your vehicle's chassis.

  • Mike from Santa Rosa Beach, FL

    Posted on 8/5/2015 1:48:29 PM

    How do you determine the MAX AMP INPUT/CHARGING AMPS a Capacitor can handle??? I would LIKE to connect a capacitor directly to the ALT. Output(My Stock one is 130AMP), to isolate the sub-woofer and any other amplifier circuit I add in the future. I have found that the MAXWELL Super-caps (2.7VOLT 350-500F), with 6 of them bundled together, 16.2VOLTS and 3000F, would make a great substitute for the car battery, as long as they don't drop below 10-11VOLTS or go without being charged for more than 2 days... What worries me, will the 130AMPS coming from my ALT destroy the caps??? THANK YOU SO MUCH in Advance!!!

  • Buck Pomerantz from Crutchfield

    Posted on 8/6/2015 10:23:00 AM

    Mike, The capacitors made for car audio application are all made to handle the high current that flows when the cap charges and discharges. You'll have to find out the current-carrying capacity of your super caps from the manufacturer.

  • Justin Stefko from Newton

    Posted on 8/6/2015 12:03:25 PM

    Can power capacitor be rebuilt or repaired? I have a 30 figured that doesn't work

  • Buck Pomerantz from Crutchfield

    Posted on 8/6/2015 4:48:51 PM

    Justin, I'm afraid not. Capacitors are replaceable, but not repairable.

  • Kel from Nashville

    Posted on 9/17/2015 1:55:57 PM

    I am about to change vehicles, and was wondering if I should replace my capacitor. I have used the capacitor for a little over 3 years and didn't know if replacing it was necessary?

  • Buck Pomerantz from Crutchfield

    Posted on 9/17/2015 2:11:55 PM

    Kel, It is not absolutely necessary to replace your capacitor, but it may help if your car's headlights dim a little when your music plays loud.

  • Kiran

    Posted on 10/7/2015 7:31:33 PM

    My battery capacitor isn't charging fast it take at least 8 hours and is only half charged,, is there a reason for this?

  • Buck Pomerantz from Crutchfield

    Posted on 10/8/2015 10:18:48 AM

    Kiran, It sounds like your capacitor has failed - it's probably leaking its charge internally.

  • Trey from Uvalde

    Posted on 11/5/2015 2:40:20 AM

    It may sound stupid but, can you connect your capacitor to the same ground area as your amplifier?

  • Buck Pomerantz from Crutchfield

    Posted on 11/5/2015 11:55:24 AM

    Trey, The ground point used by your amplifier is a great place to also ground your capacitor.

  • Jason Flanigan from LEXINGTON

    Posted on 11/15/2015 3:50:33 PM

    Is a 20 Farad Capacitor on a 1500watt amp to big

  • Buck Pomerantz from Crutchfield

    Posted on 11/15/2015 5:21:58 PM

    Jason, Like this article states, there is no electronic penalty for using large value caps - the larger the cap, the faster it gets ready for the amp's next big hit

  • joe from Cincinnati

    Posted on 11/16/2015 2:54:29 PM

    Hi. I have a 300W powered 10" sub Rockford Fosgate. My lights do not dim, etc. I bought 1.5 farat capacitor, but do I even need it, or will it provide any benefit? It's installed in a 2015 car that has a bunch of electronics, etc, and i didn't want my amp to kill my alternator faster, or worse, cause an electrical problem by pulling directly from the battery, instead of using a capacitor. Am I being paranoid? Is the capacitor beneficial in my case?

  • Buck Pomerantz from Crutchfield

    Posted on 11/16/2015 3:34:43 PM

    Joe, I would think that a 300 watts RMS amp added to a car's stock electrical system would not need a capacitor, but wouldn't be harmed by one either. The only way to know for sure is to remove the capacitor and see if your lights dim on heavy bass hits. If they do, re-install the cap. If they don't dim, then you never needed it to begin with.

  • Matt from Indianapolis

    Posted on 11/23/2015 5:16:50 PM

    I have a cap with a meter and it does not have a remote turn-on connection. Do I need to be worried about this draining my battery?

  • Buck Pomerantz from Crutchfield

    Posted on 11/24/2015 1:03:06 PM

    Matt, I think the current draw of your capacitor's meter is as small as your vehicle's clock and won't drain a healthy battery when left unused for a while. If the battery is weak or needs replacing, however, that small draw may be enough to leave you powerless.

  • Bret Weaver from Clinton

    Posted on 11/28/2015 3:32:53 AM

    How do I wire up 2 amp' s to a capacitor?

  • Buck Pomerantz from Crutchfield

    Posted on 11/30/2015 2:35:36 PM

    Bret, Here's a diagram that shows how a capacitor hooks up in a typical 2-amp system.

  • Todd from Lexington

    Posted on 12/9/2015 10:04:17 PM

    I noticed the mention of using same size wire for amp and capacitor. I used 8 gauge from battery to cap and 4 gauge for the small cap to amp wire. Should I make it all 4 gauge?

  • Buck Pomerantz from Crutchfield

    Posted on 12/10/2015 9:57:12 AM

    Todd, The size power and ground wires to use in a system is dependent solely on the total power requirements (current draw) of the amplifiers. If you're using one amplifier and it requires 8-gauge power and ground wiring (see the owner's manual for that specification), then 8-gauge will do for the capacitor, although using a larger wire won't hurt anything.

  • Chris from Brunswick

    Posted on 12/21/2015 11:56:05 PM

    I noticed on my capacitor there is a third spot for a remote wire. So with the remote turn on coming from the radio to the amp like i normally have it, should i run the remote wire from the radio to the capacitor, then jump it from the capacitor to the amp? I dont understand how to hook up the remote turn on. Ive been trying to find out how and i can't find any answers!!

  • Buck Pomerantz from Crutchfield

    Posted on 12/22/2015 12:02:47 PM

    Chris, If your capacitor uses a remote turn-on, for an onboard meter for instance, it doesn't matter if it gets the connection directly from the receiver and then daisy-chain it on to the amp, or the other way around. Most people just run a jumper from the amp's remote connection to the cap's.

  • Chris from Brunswick

    Posted on 12/22/2015 4:44:56 PM

    Thanks for your response. So if i jump a seperate wire from the remote terminal from the amp to the third terminal on the capacitor it wont hurt anything will it?

  • Buck Pomerantz from Crutchfield

    Posted on 12/23/2015 12:19:30 PM

    Chris, No, it won't hurt anything - that's how you hook it up. It sounds like you don't have the instructions that originally came with your capacitor. You should know that a capacitor can be dangerous; it can charge and discharge so much power so very quickly that it can weld metal objects, like tools and jewelry, and melt its own insides out. Please follow the steps in this article, or from another reputable source, telling how to hook up a capacitor safely.

  • yannick from mauritius

    Posted on 12/28/2015 10:44:52 AM

    hi, note that i have a pioneer champion series amplifier powering a JBL subwoofer of 300 watt and 4 speakers of 80 to 100 watt for the high. when i play music for some time at higher volume and the bass are kicking hard, after a certain period of time, the music stops for 1 to 2 seconds and continue to play again. i therefore need to play the music below level 10 (30 to be the highest) so that the periodic "1 second cuts" stop. do you think that it's the power consumption and that i will need a capacitor to resolve this issue or it is being caused by another issue? Thanks

  • Buck Pomerantz from Crutchfield

    Posted on 12/28/2015 4:03:17 PM

    Yannick, Here are some things to check for: Are you using 4-gauge power and ground cables for your amp? Are there any loose connections? Is the ground wire absolutely secure - bare metal-to-bare metal contact? If you bought your amp from Crutchfield, you could call Tech Support for free help troubleshooting your system. Their toll-free number is on your invoice. If you purchased your equipment elsewhere, you can still get expert Crutchfield Tech Support - 90 days-worth for only $30. Click on this link for details.

  • Buck Pomerantz from Crutchfield

    Posted on 12/29/2015 12:51:21 PM

    Yannick, Sorry, I just now figured out that you don't live in the U.S. and so can't buy Crutchfield Tech Support. Your problem, 1 to 2 second cut-out every once in a while, sounds more like a loose connection or defective amplifier than anything else. I suggest you take your vehicle back to the installers and have them diagnose and fix the issue.

  • Ryan from Fort Wayne

    Posted on 1/7/2016 2:53:21 PM

    I recently purchased a new capacitor. While unwrapping it I cut through the clear plastic wrap or heat shrink around the cap. It had the brand name on it. Is the wrap needed or can I peel it off and just have the bare aluminum. I wasn't sure if the wrap was an insulator or just for appearance. Thanks!

  • Buck Pomerantz from Crutchfield

    Posted on 1/8/2016 3:25:33 PM

    Ryan, Maybe the wrapper serves as an electrical insulator, maybe not. The only way to find out for sure is to check with the manufacturer.

  • Chris

    Posted on 2/3/2016 4:55:31 PM

    If i am running 2100 rms amp with 2 1000 rms subs , what kind of capacitor do i need? I am guessing 3 farads?? And also a 600 rms amp inside for highs ... Also planning to put a battery in trunk as well

  • Buck Pomerantz from Crutchfield

    Posted on 2/4/2016 3:37:49 PM

    Chris, Like the article says, the rule of thumb is to put in 1 Farad of capacitance for every 1,000 watts RMS of total system power, but there is no electronic penalty for using a larger value cap. A 3 Farad cap will be fine for your system to help prevent light-dimming when your music hits hard.

  • Edgar from Fontana

    Posted on 2/8/2016 4:48:15 PM

    Hi I'm having a problem with my battery drained and my compacitor staying on my compacirtor has a meter on it and I already plugged in the remote but the capacitor still stays on what's the problem?

  • Buck Pomerantz from Crutchfield

    Posted on 2/9/2016 11:41:53 AM

    Edgar, Capacitors, in car audio applications, are passive electronic devices connected to constant 12-volt power and ground, so they are always on. If you are referring to a voltmeter display, the remote lead is supposed to connect to switched 12-volt power that turns off when the car is off. You may have to find a different spot to connect your remote lead. Some capacitors have displays that sense when power flow stops and turn themselves off after a few minutes.

  • Dallas

    Posted on 2/10/2016 9:35:37 PM

    Hi, i have a BOSS CAP8 capacitor and i was wondering if it was okay to just use the capacitor as a positive distribution block?

  • Buck Pomerantz from Crutchfield

    Posted on 2/12/2016 10:42:42 AM

    Dallas, It probably won't hurt anything installing your capacitor's positive terminal to the main power cable and a couple amplifier positive leads, if the main power cable can handle both amps. But it will do the most good connected to the subwoofer amp's positive lead only and as close to that amp as possible.

  • Travis from Hope mills, NC

    Posted on 3/2/2016 12:27:16 PM

    Have 2 questions I have two 12" subs at 1200w with a 1200w amp 1.5f capacitor I plan on adding a 400w amp to power two tweeters 1) will this be too much power for my cap and have negative effects? Or is the power draw from the tweeters manageable without increasing the cap size 2) might sound lazy but is it possible to wire that second amp through the capacitor, using it as a distribution block, and if so does the same gauge wire need to be used as the 1200w amp

  • Buck Pomerantz from Crutchfield

    Posted on 3/2/2016 3:39:07 PM

    Travis, Not knowing exactly what amplifiers, tweeters, subs, or capacitor you have makes it impossible to give advice on how it all could get wired together. 400 watts seems like a huge amount of power for a set of tweeters, but that may be a peak spec and you'll be okay. And using a cap for a distribution block is a bad idea - how do you know that the main power wire from the cap's positive terminal to the battery can accommodate both amps? Capacitors are really only effective providing jolts of power for a subwoofer amplifier anyway.

  • Brett from Newtown, PA

    Posted on 3/3/2016 9:46:22 PM

    Hi I'm finishing up the install of my car audio system this weekend and have a question. My car is a 1965 Mustang and I'm using a 1.5f capacitor with a 1500 watt 5 channel amp. Before big audio system, I regularly take the battery terminals off and put the battery on a tender to keep it "fresh" since I don't drive the car very often. I assume then since I remove the battery supply, the cap will discharge as from what I'm reading about now with capacitors (sorry I'm all new to car audio world). Is there anything you'd recommend in my case then? Do you know could I leave the terminals bolted/quick clipped on the battery and pop the Tender's clips right on there to keep the battery charged up, through the down times? Thank you much!

  • Buck Pomerantz from Crutchfield

    Posted on 3/4/2016 4:37:19 PM

    Brett, You can definitely leave your battery hooked up in your Mustang while you keep the battery charged with a battery tender.

  • Jeremy from Grande prairie

    Posted on 3/8/2016 6:04:41 PM

    I'm installing a 300w rms amp/300w rms subwoofer in my Toyota Echo. I have a 90amp alternator and a 30-40 ah battery. The vehicle isn't fully loaded so it has manual roll up windows no a/c etc... (Also I bought an Aftermarket pioneer stereo) anyways the question is do i need this 2 farad capacitor or will it just harm my battery or alternator and provide no real benefit. I don't know if my lights will dim I haven't installed the sub/ amp yet

  • Buck Pomerantz from Crutchfield

    Posted on 3/10/2016 9:26:38 AM

    Jeremy, I don't think that amplifier will be too much for your car's electrical system to support, so you probably won't need a capacitor at all. Even if you installed one anyway, it would not harm your alternator or battery.

  • Juan from Minneapolis

    Posted on 3/15/2016 12:48:31 AM

    I have mine wired the 12v output of the cap(10 farad) to a DST then from there to feed my two amps one is a 4 channel and the other one is a monoblock Im a wasting power by doing this? is it better to just run the monoblock from the cap? also I also read that all the grounds should be at the same point if possible, I have my mono block ground attached to my Cap because it has two Ground terminals. Is this wrong?

  • Buck Pomerantz from Crutchfield

    Posted on 3/16/2016 4:30:47 PM

    Juan, It is best to mount and connect a capacitor by the subwoofer amplifier because that's where it does the most good, but I don't think it'll hurt anything installing it elsewhere on the power line. The rule of thumb for audio installations is to have all the gear grounded at the same point, but if you aren't getting any noise or interference with the way you have your grounds, go ahead and leave them as they are.

  • randy brillon from spokane

    Posted on 3/16/2016 4:54:16 PM

    im having an issue with my Capacitor i got for my stereo it seems to want to stay charged up even when im not bassing out and the last couple days its ran my bat dead by i assume its trying to stay charged up all night draining my bat what i want to know is it ok to put a power cut off to cut the power from the m,ain bat to the capacitor? like an inline toggle switch between the power distribution block and the capacitor? will it hurt the capacitor to have power cut off from it all the time ?

  • Buck Pomerantz from Crutchfield

    Posted on 3/17/2016 9:39:25 AM

    Randy, A capacitor is supposed to stay charged when hooked up. Like the battery it's connected to, it's supposed to just sit energized without draining the charge when no current is flowing. Try disconnecting the capacitor and see if that was the reason your battery drained. Maybe something besides a defective cap is the culprit. And do not put a switch in-line with your capacitor. Turning on and turning off the current flow suddenly to a capacitor will most likely damage it.

  • Jason from Fort Worth

    Posted on 5/23/2016 1:27:24 AM

    Buck question for yea. How do you know if a cap has gone bad in your system? Had the cap for 3 years with no probs. No leak in the cap. Has electronic display, display does Not stay on after charged. Uses a resistor to charge cap up however drains the battery after charged? 500k microfarad Scosche capacitor running on a 700 watt 4 channel amp with 50 amp fuse. Replaced the battery, charged the cap back up, drained the battery quick again. Removed the cap, hooked the amp up direct, car started right up. My thought is the current is back feeding causing a short in the battery?

  • Buck Pomerantz from Crutchfield

    Posted on 5/23/2016 12:54:59 PM

    Jason, If your battery drains when your capacitor is in the circuit, but does not when the cap is not in the circuit, then I'd leave the cap out. It sounds like it's developed an internal short. Usually, an electrical system won't need a capacitor to handle an amplifier capable of pulling 50A.

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