secondary battery, diode isolator, am I going to burn it down?

[Eamon Conheady]

Here you go, anything you need to know is in this thread.

http://www.stevemeadedesigns.com/board/topic/178148-bump4lifes-supercapacitor-overview-and-testing/

Thanks for the link! That's legit, it looks like it accomplished exactly what I was hoping. Use the battery as a buffer that prevents voltage from getting too low, but the caps will keep the voltage higher and reduce the instantaneous demand placed on the charging system. I'm sold.

So...you are willing to spend hundreds of dollars on super caps but not $100 (including shipping) on a fucking 25' run of 1/0 OFC...

Of course I would do it right, but is it necessary/would it even offer a benefit? I'm not convinced there would be any benefit to replacing the current 2x 4AWG runs with 1/0 wire. Two runs of 4AWG is about the same as a 2AWG run. At less than 20', each strand can carry 250A max. The long first half from charging (might bypass battery for the run) would have the current balanced over the two strands, then from cap to amps, they can only have a max of 4AWG per the connectors they have. RF T1500 draws max 220A, Hertz a max of 80A.

As for what the caps can draw, the alt can put out 140A, so that's basically the max that would pass through the load balanced longer run which can handle 250A x 2, unless voltage did drop to the battery level 12.8V, then it would draw the 140A plus whatever else the system could demand (220+80=300+140=440A) <-- theoretical max. Just because a cap can deliver 10,000A in a millisecond, it does not mean it ever will be possible to; it cannot deliver more than is being demanded. The amount discharged is determined by how far the voltage drops. If they're charged to the system's max of 14.4V and then discharge to battery level 12.8V, the 500F bank could deliver 6,400W if that voltage drop occurred over 1 second. Thats almost 300% what my system can draw, so that wouldn't happen. Also, the point of caps is that they would ease the voltage drop, so it would never really even happen as fast as theoretically possible.

I'm going to guess he hasn't found out how expensive they are yet.

http://www.mouser.com/ProductDetail/Maxwell-Technologies/BMOD0500-P016-B02/?qs=sGAEpiMZZMuDCPMZUZ%252bYl1%2f%2f0aiL7qGyLVWPq48phMw%3d

$560 for a fully assembled, beautiful 500F 16V bank. 1/0 wire is $100? no big deal. Is it necessary or even beneficial? I wonder what kind of voltage drops I'm seeing right now...

Does anyone know what the best way to wire these up would be? Straight from the alt, or off of the starting battery? Is there a benefit to having a secondary battery in the back with these? I'd think replacing the front with a higher capacity one would only even be warranted if the voltage regularly dips far below the battery's charged level.

[ShadeTreeMechanic]

These super caps are great in the right application. In the right application. After your charging is maxed out and you can't make it any bigger then the caps would help. You still have the same problem. The power has to come from somewhere. All this will do is help you run your alt at its max output for a longer period. This is why they have a bad rap for killing alts. Its all in the application.

[Wehan]

Step 1: take everything you THINK you know and toss that out the window. Step 2: do what the people who do this thing for a living and/or are trophy winning hobbyist tell you to.

Starting to think this is a troll account.

[Broke_Audio_Addict]

You just don't get it,

If you aren't going to listen when people answer your questions why even ask?

Have fun burning your car to the ground, I'm out.

[Eamon Conheady]

You just don't get it,

If you aren't going to listen when people answer your questions why even ask?

Have fun burning your car to the ground, I'm out.

Yo, I am listening. I need to look at it from the physics aspect. I'm not a pro or masters at this stuff like you guys are! I'm just trying to figure out how it needs to work, and why it needs to work that way. It's why my posts are longer than a sentence or two; I'm trying to convey my understanding of the situation.

What is the reason for using larger gauge wire from the batt to the caps?

These super caps are great in the right application. In the right application. After your charging is maxed out and you can't make it any bigger then the caps would help. You still have the same problem. The power has to come from somewhere. All this will do is help you run your alt at its max output for a longer period. This is why they have a bad rap for killing alts. Its all in the application.

How can a capacitor force the alternator to run at it's maximum output longer? Is it just because the system is now able to store adequate power to drive the audio? It seems like the caps would recharge very quickly, being able to smooth the voltage and demand curves.

I don't fully understand how this stuff works, I'm not just trolling around to cause trouble. I can post some pictures of what I have set up if it would help, but I'm not sure it would make a difference in how to improve a system.

Step 1: take everything you THINK you know and toss that out the window. Step 2: do what the people who do this thing for a living and/or are trophy winning hobbyist tell you to.

Starting to think this is a troll account.

I know that I don't know much about this sh*t, that's why I'm trying to get someone's specific advice, not just "you're an idiot" responses.

It does however seem like there is good evidence to support the use of caps from people who do this for a living. Just take a look at the link that was provided.

[ShadeTreeMechanic]

The power has to come from somewhere. When the caps recharge after the bass just hit. If the alt is not big enough to meet the demand, you will only be able to turn it up so far before the voltage sags. Now you add caps. Now you can turn it up a little more. Before the alt was at max only when the bass hit. Now with the caps it also is at max to recharge the caps and hopefully before the next bass hits. It will work and sound great but it will be at the expense of the alt. When it finally goes out you will be able to get an HO alt. Which is all you need to begin with.

[Wehan]

You want specific advise? OK. Run a battery in the trunk, go get a group 34 Napa Legend AGM battery. Run 1/0 OFC from your front battery to the rear battery and don't forget to use a 300a fuse at both ends. Ground the trunk battery with 1/0 OFC. Connect your amps to the trunk battery with 4ga wire and 150a fuses (or whatever Rockford recommends). Keep an eye on your voltage and bump as hard as your alternator will let you. You don't need an isolator, you don't need a flux capacitor or a super duper capacitor. just remember this: K.I.S.S. = Keep it simple stupid.

Also, you can pull all of this when you get ready for a new car, even a high output alternator can in some instances be re-cased to go into another vehicle.