Jstas

sntnsupermen131

ok I know you can give me the full explanation on this. I'm rewiring my entire system to have one 1/0 wire from the battery to the caps...then from the caps to the amps. All the fuse ratings add up to be about 150A, so on the 1/0 line, I'll be putting a 150A fuse. Here's the question. If the wire is allowing 150A to go through the wire, why does it not blow the amps that are rated at 40A?
I know it wont blow them, but I don't know why and I figured you were the guy to ask.
Thanks
-Cody

Jstas

Simple. The amp will not draw more current than the amperage rated on the fuse. It already is fused but the fuse in the amp will only protect it if it blows. Sometimes, the current spike can be so large that the fuse doesn't do anything.

Anyway, have the 150 amp fuse close to the car battery. That is where that will go. Then, run the power wire back to the spot where you will be having amps. Grab a distribution block with provisions for fuses. Rockford Fosgate makes ones that will handle large guage wires. So does Scosche but Cruthfield doesn't have either. I imagine you could pick one up at sounddomain though. They are relativly cheap. Usually 20-60 dollars depending on the name and number of outputs.

Take your main power line and run it into the fuse block. Then, for each amp, get a fuse to fit the fuse block that matches the fuse rating on each amp. Then, run a power cable from each fuse to it's matching amp. If you need the 0 guage wire for a sub amp then run the o guage wire on the other side of the distribution block too.

What that does is if a power surge comes down the line, it hits the 1.50 fuse and kills that rather than the 200.00 amplifier. Me, I'd rather lose the fuse and possibly the distribution block than the amp. The benefit to the 150 amp fuse at the battery is so that if an amp goes bad or you accidentally ground out the power wire, the 150 amp fuse blows instead of your battery/charging system.

What can cause power spikes? A bad voltage regulator can cause a power surge that doesn't stop surging. Most alternators can put out alot more power than they do. Its the voltage regulator that kees them between 12.2vdc and 14.4vdc. Also, a bad cell in a battery can cause a voltage spike. Bad grounds, a bad starter, a badly ground ignition system, all that stuff can cause problems. On the other side, a bad amp can cause a power surge or a ground fault. A broken speaker coil or the wires that run to the cone can cause a ground fault to the magnet and/or chassis and cause impedance to rise drastically. That can cause power drains and damage amps and stuff too. Lots of stuff can happen and the fuses are there as a last-resort stop-gap to shut off the power if somethings goes wrong. It's always better to have the fuses than it is to rely on the amp fuses.

You really shouldn't ever have to replace teh fuse in the amp unles it just plain flat-out wears out. I only had 1 amp do that to me so far. My little Kenwood blew it's fuse. It was operated daily with the original fuse for like the 8 years I have had it (up until last October) and the fuse just wore out and popped. I replaced it and it has worked ever since. I've popped quite a few of the power line fuses though. I accidentally grounded out a screw driver on the amp chassis when I was installing the power line and popped the fuse. Not only did it save the amp, it probably saved me 'cause my arm hurt pretty bad after that stupid stunt. Now, the fuse is the last think I connect. I'll leave the power line dangling withe the plastic fuse holder cuy and then, when everything is done, I slip the fuse holder together with the fuse and everything works out peachy keen. Usually!

Jstas

Actually, some additions.

Number one, some amps do not come fused and you absolutely need a fused power line and even a distribution block incase the fused line is fused too high for the individual amps. Because hooking up the power line to the battery without any fuses inline will surely hurt something eventually and isn't a good practice to get into.

With the capacitors you are using, you may want to put them after the fused distribution block and on the lines of teh amp(s) that will use them the most, like the sub amp. If you put both capacitors before the fuse block, all amps are going to draw power from them and then you can hurt the weaker amps because the stronger amps will pull more current. If the current level for the weaker amps falls too low, you could end up hurting the amp because it will still want to draw it's rated current. That can melt the transformer for the power supply and cause a serious ground fault that could actaully start a fire.

Not my idea of a good time.

sntnsupermen131

how would I put the distribution block before the capacitors?
Heres what I'm thinking...battery...1/0...150a fuse...1/0...distribution block...caps...amps
when its all said and done i will have 2 caps...4 amps...
but how do you have the block before the cap?
b/c u have the 1/0 going to the block...then all the wires from the block to the caps...then all the wires would be touching again...that would still work?
its going to be hard to find this block...i need an 1/0 input...2 4awg outputs and 2 8awg outputs
-Cody

Jstas

OH! One more thing!

For GROUNDS, get an unfused power distribution block. Match the ground guages for each amp and run them into the individual leads from the power distribution block. Then take the 0 guage wire and run a ground wire from the single lead to the ground.

I never understood why companies tell you to use a smaller ground wire than you do power wire. Power doesn't just dissappear. It changes as it goes through your system and your current on the ground is going to be less than the current going in but there power is still there.

Think of your bath tub. Fill it with water. You have a 2-3 inch hole filling the water up right? How big is your drain? The initial hole is usually 3-4 inches but drops down to 1 and 5/8ths in some cases. So even with the drain open the tub will still fill with water. It's meant to be that way. A bath tub is supposed to hold water and if the drain hole could flow more water than the faucet, the bathtub would never fill up. We don't want that. For electrical circuits, we don't want power backing up. We want it moving otherwise we have problems like noise and hurt components. So we need to make the drain (ground) as big as the faucet (power wire). Believe it or not, it helps in the quality of sound. If the ground wire isn't big enough, power starts looking for different ways to get out. If it can't get out through teh ground from the amp, it'll get out other places like the radio chassis ground or the antenna lead or the amp chassis ground or where it can. That causes ground loops which cause feedback cycles which are audible. Not good. So make your ground wires big enough so that you don't get that feedback.

That's kind of an over simplification but I don't buy amp wiring kits that do not have a ground wire at least as big as the power wire.

Jstas

Originally posted by sntnsupermen131
how would I put the distribution block before the capacitors?
Heres what I'm thinking...battery...1/0...150a fuse...1/0...distribution block...caps...amps
when its all said and done i will have 2 caps...4 amps...
but how do you have the block before the cap?
b/c u have the 1/0 going to the block...then all the wires from the block to the caps...then all the wires would be touching again...that would still work?
its going to be hard to find this block...i need an 1/0 input...2 4awg outputs and 2 8awg outputs
-Cody

You don't need the caps for all of your amps. You won't need them for highs, you will most likely want the for subs. So don't wire caps on the power leads that goto the highs amps. If the caps are for teh subs and you have 1 or two sub amps, put your capacitors on those leads. Why waste the extra power on the highs? The subs will need the extra voltage support the caps provide, the highs and mids most likely won't.

So if you have 4 amp leads, 1 for highs, 1 for mids and 2 for subs, put the caps on the power lines that goto the subs. That's just an example, I don't know your exact intended setup.

See what I'm saying?

sntnsupermen131

i was thinking just have the 150A fuse, run everything to the caps, ground everything at the caps with a piece of 1/0, then run power wire to the amps...no more fuses...no distribution blocks
-Cody

sntnsupermen131

Originally posted by Jstas
You don't need the caps for all of your amps. You won't need them for highs, you will most likely want the for subs. So don't wire caps on the power leads that goto the highs amps. If the caps are for teh subs and you have 1 or two sub amps, put your capacitors on those leads. Why waste the extra power on the highs? The subs will need the extra voltage support the caps provide, the highs and mids most likely won't.

So if you have 4 amp leads, 1 for highs, 1 for mids and 2 for subs, put the caps on the power lines that goto the subs. That's just an example, I don't know your exact intended setup.

See what I'm saying?

your point is getting more across...what about this...can i run the 1/0 to the block then run 8awg straight to the highs...have one 4awg running to the caps(with an 80 amp fuse...2 amps both with 40 amp ratings)...then from the cap have 2 4awg wires...one to each amp?
-Cody

Jstas

Well, what is your distribution of amps? 2 amps for highs, 2 amps for lows?

If it's 2 amps for highs, get 2 2 line distro blocks. Run the 0 guage into one block and the 0 guage from the 1 block into the 2 blocks. make the 1st block unfused. The 2nd 2 blocks would be fused. Put fuses for each highs amp in the 2nd block and then run 4 guage wire to the amps. Better to have too much wire than not enough. The othe lead, put the 2 caps onto that lead and then run them to the distribution block. Then fuse the two lines in the block with 40 ampo fuses and then to the amp.

That will seperate the caps from the highs and reserve all of thier extra juice for the lows.

sntnsupermen131

ok i think i got you know
battery...1/0...unfused block with one input...2outputs...at the same block...have 1 of the outputs go straight to the caps...from the cap run the wire(would this still be 1/0...itll only 900 watts) to another block with 2 40amp fuses...each output would have 4 awg and run that to each sub amp
yes i have 2 sub amps(rf 450s...450rms each)
2 highs...one is for the mm6s...rf500.2 delievers 175 each channel...the other amp will be a 201s...50x2 to run the momo 4x6s when i get them
ok
then you go back to the original unfused block
run 1/0awg from unfused to fused block for highs
4 awg from fused block to the 201s and 500.2
no caps on that line
you said to fuse on the unfused block...how do you do that?
this is probably the wierdest wiring job ive ever done
-Cody

Jstas

No no no. scratch what I first said like 2 or 3 posts ago.

What you will need to do what I would do:

0 guage wire
- power and ground
4 guage wire
- power and ground

1 2 lead, unfused power block
2 2 lead fused power blocks
1 4 lead unfused power block

buncha ends and connectors if you want it to look pretty.

take your 0 guage power wire and run the 0 guage into the 150 amp fuse. Run the wire from the fuse to the 2 lead unfused block. Run 0 guage out the 2 outputs. One 0 guage lead goes to the highs fused power block. The other 0 guage lead goes to the caps. Wire up the caps and send 0 guage from the caps to the 2nd fused power block. Now, take the 4 guage wire and wire the out puts of each power block to an amp. The highs fused power block outputs got the highs and the same for the lows.

Now, check the fuse ratings on each amp and put a fuse in the fuse that is the same as the fuse rating on each amp. So if you had this list of current draws for the amps:

20 amps
25 amps
40 amps
40 amps

You would put a 20 amp fuse in the holder with teh lead going to the amp drawing 20 amps. You would put the 25 amp fuse on the lead going to the 25 amp draw amp and so on. This would give you your individual amp protection because a 150 amp fuse would still allow power spikes that could blow any one of your amps in your setup.

After that, take your 4 guage ground wires and run each one of them to that 4 spot, unfused powerblock. Then run the 0 guage ground wire to your ground spot from the 4 spot power block. That creates a common ground of ample size and will help eliminate any noise problems you might have.

Also, what I mean by fused and unfused is, some power distribution blocks have provisions for fuses in them. Sometimes they are called fuse holders but I don't think that is an accurate name. They don't just hold fuses. If you can't fin any, no sweat. Get the cylindrical in-line fuse holders and run them that way. This is an expensive option. Initial cost is high but when you have a power spike, repair bills can have an insiginificant hit on your bank account and that is the best part. It will also ensure long life for your equipment.

NOW! If only someone would make a DC line conditioner!

sntnsupermen131

i understood everything but i dont know how you would do the ground...where is at?(as in when..before the fused distribution block but after the 150a fuse?)...how do you actually do it?
-Cody

sntnsupermen131

aww man...you left...thanks for all your help...sorry...i know im a little slow
-Cody

Jstas

The ground leads from teh amplifiers dude. They all have the ground leads.

The caps can get thier own ground, They come in the system long before teh signal does and truthfully, the caps have teh ability to put out a discharge strong enough to revese teh flow of current on the ground wires and destroy the amplifier and maybe even speakers in a pretty nasty mess. Ever see what happens to a capacitor when you reverse teh current flow?

KAPOW!

That's what can happens. When it does, it blows electrolyte everywhere!

The common ground is for the amplifiers because you should put a common ground on anything that processes the signal. Even your head unit and, if you have them, equalizers and crossovers should be sent to that common ground if possible.

sntnsupermen131

i get ya!
you had me confused with the common ground and the block but now i understand
what would be the use of 150A fuse by the battery?
-Cody

sntnsupermen131

wait wait i know i know!
its b/c you said that if the surge is too big for the fuse...it might not blow it correct?
so if its too big for a 50a it probably wont be too big for a 150
am i right?
-Cody

Jstas

If you don't fuse the battery and you end grounding something out like when an amp goes bad or you do something stupid like drop a screwdriver or wrench and cross two leads, you can get a major current draw that could kill the battery and your electrical syste. The fuse will blow at 150 amps and stop that draw before the battery and charging system get over-drawn. If they get over-drawn, damage occurs and it can also be messy. I've seen cars get totalled out by an insurance company because a battery blew up and threw acid everywhere. VERY expensive to fix.

Also, that fuse could stop you from dying because you can be grounded out too. The reason you need a 150 amp fuse is because all of your amplifiers combined should draw a maximum amperage of 150 amps. If you put a 100 amp fuse in there, every time you turned the stereo up, the fuse would blow. Wouldn't make sense to do that. So you use a fuse that will allow your maximum current draw but stop any larger current draw to save your electrical system in the car, any equipment that wasn't damaged by whatever went wrong and possibly even you.

Make sense now?

Jstas

Originally posted by sntnsupermen131
wait wait i know i know!
its b/c you said that if the surge is too big for the fuse...it might not blow it correct?
so if its too big for a 50a it probably wont be too big for a 150
am i right?
-Cody

Yeah, that's why you use the individual fuses farther down the line on the power distribution blocks. Because a 75 amp power spike would kill your amp that draws 50 amps but your 150 amp fuse would not be affected by it at all.

The reason you put fuses after the capacitors is so that if they ground out or something and try to cram too much power into your sub amps, the fuses blow and you keep amps but lose capacitors. You want to isolate power sources in this manner to protect the sensitive equipment and other electrical components.

Batteries and capacitors are fairly stable power sourcse but they are flaky and can easily become unstable. So protect your stuff from them.

Jstas

That's also why a single amp system does not need another fuse and distro block. If your amp draws 40 amps, you put a 40 amp fuse in the holder near the battery and be done with it.

sntnsupermen131

ok...thanks for all your help
originally i was only going to have 1 fuse the 150 then run to the caps...then have 4 wires running from cap to each amp...wouldve been cheaper...wouldve looked "cleaner"(less wires)...but i dont want my stuff to blow...ive had to send both my subs back, my bd1000 **** the fan, and i think one of the new amps i replaced it with isnt working
im doing something wrong...lol
thanks again...thats all my questions
-Cody