4 - 12" + 1200.1 = Power cap?

[jlaine 10+ year member]

Originally posted by ftgu Dude , do you know ANYTHING about the differences in a DEEP-CYCLE and a regular battery? For Instance..Deep-cycles are used on boats that don't have alternators. And can supply the cranking amps that it takes to start the boat(500-1000A or more), over and over and over and over and over and over and over and over and over and over and over and over again without needing charged. SO....If you use a cap before this battery, when the battery does need juice(and it wont need much) it will pull A LITTLE from the cap(maybe a quarter farad in capacitance worth of juice). Which would not strain the alternator to refill.

Where praytell did you find a onboard/outboard engine without an alternator or some form of self-support? I'd like to see this one...

 

[ftgu 10+ year member]

3 of them in my yard, mine (90Hp Mercury on a 15ft Thunderbird), my dads, and my brother-in-laws. Also my father owns a boat repair shop on Lake Erie, and i have pretty much seen them my whole life.

usually outboards, but others as well.

 

[Savant 10+ year member]

Originally posted by ftgu Dude , do you know ANYTHING about the differences in a DEEP-CYCLE and a regular battery? For Instance..Deep-cycles are used on boats that don't have alternators. And can supply the cranking amps that it takes to start the boat(500-1000A or more), over and over and over and over and over and over and over and over and over and over and over and over again without needing charged. SO....If you use a cap before this battery, when the battery does need juice(and it wont need much) it will pull A LITTLE from the cap(maybe a quarter farad in capacitance worth of juice). Which would not strain the alternator to refill.

I think you are missing the point of conservation of energy.. If the amp draws X units of energy, it has to come from someplace.. if it comes from the deep cycle battery, the battery has to get it from some place.. if that some place is the cap, it has to get it from some place.. which is your atlernator.. If the amp is tapping the deep cycle, the deep cycle isn't just gonna pull tiny bits and peices from the cap, it's gonna **** on the system until it's full, the cap might delay the hit to the alternator from the deep cycle, but that delay is only on the order of seconds.. then the cap is back to the 'common' voltage and does nothing to 'help'.. then it's back on the alternator to charge BOTH the cap and battery..

There is also the consideration of heat as energy, and each device you put inline is gonna waste energy as heat (with all these amperes being pushed about and so on).. so, putting in a cap actually WASTES some energy when it has very minimal benifit to the system..

As for boats with motors and no alternators, yes.. they have ....... ****... a little magnet on the flywheel (type thing) that breaks another magent to create current for spark... so they don't need alternators to supply electrical power.. the whole point to deep cycle batteries is that they store a LOT more potential than normal batteries so you can run running lights, bilge pumps, etc... and start the engine.. When the battery gets too low, you have to charge it with a charger..

 

[ftgu 10+ year member]

OK smart guy....If a deep cycle battery is rated at 70 Ahr , what does this mean? (you're gonna have to look this up, huh?)

What does deep cycle mean?

Deep cycle means using the battery in an application that will typically discharge 60% to 70% or more of the batter y capacity. An automotive battery is an SLI (starting, lighting, ignition) battery. It's plates are designed to deliver maximum power for a short duration. Starting a car typically discharges an SLI battery only 1% to 3%. When an SLI battery is used in a deep cycle application, or in a vehicle with heavy accessory loads, the battery life will be shortened proportionally to how deeply it is cycled on a regular basis.

Anyway, We can argue about this for years to come, but it is't worth my energy or time.

 

[Savant 10+ year member]

Originally posted by ftgu OK smart guy....If a deep cycle battery is rated at 70 Ahr , what does this mean? (you're gonna have to look this up, huh?)

 

What does deep cycle mean?

Deep cycle means using the battery in an application that will typically discharge 60% to 70% or more of the batter y capacity. An automotive battery is an SLI (starting, lighting, ignition) battery. It's plates are designed to deliver maximum power for a short duration. Starting a car typically discharges an SLI battery only 1% to 3%. When an SLI battery is used in a deep cycle application, or in a vehicle with heavy accessory loads, the battery life will be shortened proportionally to how deeply it is cycled on a regular basis.

 

Anyway, We can argue about this for years to come, but it is't worth my energy or time.

No, I don't have to look it up.. that's 70 Amp Hours.. or, you could **** 70 amps of current for 1 hour.. or, 1 amp for 70 hours..

All the deep cycle means is it stores MORE POTENTIAL.. based on the plates (number and thickness).. A normal car battery isn't expected to run as long as a deep cycle since the CAR has an ALTERNATOR that supplies power while the car is running.. Boats run TINY little running lights on their batteries.. and pumps that kick on once in a while.. You CAN run your boat on a car battery if you like, you just don't get juice for as long.. Why do you think it costs SO much more for a deep cycle? Certianly not because they are designed with more storage potential.. no no.. Hmm.. and you could NEVER use a deep cycle battery for normal car applications.. nope, deseil trucks don't use deep cycle either, stricktly for boats cause they act sooooo differently than normal batteries..

You are right, we could argue this till the cows come home, but you are also right that there is no point to it..

The only place you can put a cap that will help is JUST before the amp, so it can give it's juice directly to the amp when needed and no other storage devices are needed.. but if you are constantly ******* from the cap, you will still burn out your alternator.. caps have a very limited range of usefullness, before that they serve no purpose and after that you will still melt your alternator.. Personally, I'd MUCH rather put that $150 toward a much better alternator (or get one rewound) and have a much more stable charging system.. Just me

EDIT: The real problem with caps is, most people think they GENERATE power and end up burning out their alternators because they bought a cap to solve a problem that a cap shouldn't be solving... If everyone uderstood the limited use of a cap, then there would be no issues from my perspective..

 

[ftgu 10+ year member]

Originally posted by QuadPioneer Am i gonna need a power cap running my 4 12's?

using a jbl 1200.1.

If so what kind? And what wil happen if i dont?

Now, to answer your question, If you are planning on listening to test-tones for about a half hour or more, Get your alternator rebuilt. If you are gonna listen modestly most of the time and then turn it up when a good song is on (like a normal human). Then a cap or deep cycle will be fine.