Thread: Just bought a new amp, distribution block and wiring. Now I have questions.

Originally Posted by Maheriano

Here's what confuses me.

1. My Rockford amp is rated at 325 watts for 2 ohms and the MTX is 120 watts, so that puts it under 600 watts which is fine. But every Rockford comes with a birth sheet of actual recorded total RMS wattage and the sheet for this amp says 397 watts which would put it over 600 watts. Which do I go by?

Lets try and think logically. What would be worse, to underestimate, or over estimate? I am not gonna give you the answer.

[QUOTE=Maheriano;891256]2. The guy I bought the MTX amp from said it was 120 watts, but this says it's 45W x 4 @ 4 ohms meaning it's 180 watts total RMS.
http://www.cardomain.com/item/MTX4244

Again, what are you gonna do, overestimate, or underestimate.

[QUOTE=Maheriano;891256]3. The max amps for 8 gauge is 52, so when I split that in half for the 2 inputs, I get a 25 amp fuse for each wire to go into the distribution block. When I was just out to a few places asking them for 25 amp fuses for this, they looked at me funny asking if I was running a real small amp. He wanted to give me a larger fuse, and another guy wanted to give me 180 amp fuses.

There is no such thing as the max amps for wire, it is based on the length of the wire. WHy are you splitting it in half. Why are you getting 25 amp fuses? Think logically, please. Stop listening to people at the f-ing Canadien tires. They are the dumbest people on earth. Get the information you need, and get what you are told.

[QUOTE=Maheriano;891256]4. On my journey for fuses, I was looking for a 5A 25 amp fuse, and it seemed easy because they all had 5A or 3A or 2.5A or something like that on them. And the packaging for the distribution block says it takes 2 5A fuses. But when I looked at them all on the rack, it seemed like the number before the A was in reference to amps, and why would anyone put a 5 amp fuse in a piece of hardware that'll be running amps?

5A is a type of fuse, 5amp is measure of the fuses capacity. This really should not be too hard to understand.

[QUOTE=Maheriano;891256]5. Ignoring the packaging, I decided to get a 50A fuse which would be 50 amps to go near the battery on the single line. But the highest they had was 35A, and I already have a 30A in there. Why wouldn't an automotive place carry anything larger than 35 amps? It was Canadian Tire.

Because they don't carry it. Ask them why. Do an internet search, and you will find plenty. How the hell should anyone here know why they don't carry a 50 amp fuse.

Originally Posted by Maheriano

6. The 2 pages I was shown in other threads have conflicting information. One says the best fuse to go with in 8 gauge is a 30 amp fuse. But another says the max amps you can run in 8 gauge wire is 52 amps. So why isn't the best fuse a 50 amp fuse?

Wht does that mean "The best fuse" You have to fuse a wire dependent on the load. the MAX you should draw on an 8 gauge wire of 20 feet length is 50 amps, that is not the BEST fuse, that is the max. The best fuse is to fuse the circuit for 125 to 150 percent of the load.

This shows I'm believing what you say and putting those pieces together. However, when I go to buy it, these people tell me something different. So what I'm going to put together just for now to see if I get sound from everything is 8 gauge wire from each amp to the block, 2 20 amp fuses in the block, 8 gauge wire from the block to the battery, and a 30 amp fuse near the battery. I'm pretty sure it's going to blow the fuses when I turn it up, but at least it won't catch fire. Then I'll have to keep looking for bigger fuses.

Just because you split a single wire into 2, doesn't double the carrying capactiy of the single wire. THINK LOGICALLY DAMMIT.

Michael

I didn't mean doubling the carrying capacity of the single wire, I meant that if you put 2 wires into one wire of the same gauge, you can only have a max of 1/2 the amps going through each wire as the main wire can hold. So if the 15 foot wire can hold 52 amps, and you filter 2 wires into it, each wire can only be 26 amps max. This is what I've learned from my research, is it wrong?

I don't really want to get involved in the discussion (argument) but why are you over complicating picking a gauge wire. You said that 15ft of 8ga is good to 52amps. Look on your amps. They have fuses on them. Do they = more than 52 when you add them all up. If so use 4ga. If not use 8ga.

The fuses on your amps are the max # of amps the amp will pull. So an long as the wire can handle that... no worries.

Amps of the amp

Show me where your research sais that you had to split the amperage of the single wire in half for 2 whires?? You never read that, and never found that. Plain and simple. You are either making **** up in an attempt to get more info, or you are a bold faced liar.

Really now, if I have pipe that can deliver 100 gallons of water per minute, and then I split it into 2 pipes that can also handle 100 gallons per minute, do you actually think that each pipe can only handle 50 gallons now because the single pipe has to be split evenly??? Everytime you post you make less and less sense.

The maximum the pipe can supply is 50 amps. If you have 2 pipes after that, they can only supply the max available, 50 amps, but one can take 49.9 and the other 0.1, as long as the total doesn't exceed 50, and you don't exceed the other wires cvapacity, which in your case, since theyare the same, is 50 amps.

WHY would you have to split the capacity???

Michael

Okay, so I won't argue with you as I did in the past. Without understanding it still, I'll just do it.
So what you're saying, it since the max amps on the single wire is 52, I can use a 50 amp fuse there? And on each of the 2 wires going into the block from the other amps, I can use 50 amps fuses on each of those as well? Actually now that I ask it, it kind of makes more sense. Actually, it makes complete sense.....I get it.

I was just at Walmart, they don't have anything but walls and walls of LED for everything you could imagine. No wiring kits in that particular store. I'm going to try Cash Converters for a 4 gauge kit tomorrow when they're open, and also get another distribution block that'll accept 4 gauge so I won't have to worry about this headache. But theoretically I can still just use the 8 gauge right? I mean if Cash Converters doesn't have any in stock like the 1 store I was at tonight? There's 2 more stores in the city I'll try tomorrow.

Originally Posted by blkwrx

I don't really want to get involved in the discussion (argument) but why are you over complicating picking a gauge wire. You said that 15ft of 8ga is good to 52amps. Look on your amps. They have fuses on them. Do they = more than 52 when you add them all up. If so use 4ga. If not use 8ga.

The fuses on your amps are the max # of amps the amp will pull. So an long as the wire can handle that... no worries.

Amps of the amp

Seeing that the Rockford amp has a 40 amp fuse, I don't think I even need to go check the MTX. So does that confirm the 8 gauge is no good? I'm like a yo-yo here.

No, you still don't get it. At this point, I don't think you will, and perhaps anyone else willing to post in this thread will realize that no matter what you won't understand.

How the heck do you think a single 50 amp wire can supply 2 50 amp wires??????????????

How many different ways do I have to explain this to you. It is unbelievable.

Michael

Okay, first I asked if I should use 25 amp fuses in the block and a 50 amp fuse on the wire, you said no. Then I asked if I should use 2 50 amp fuses in the block and a 50 amp fuse on the wire, you're saying no again? So what is it then? I figure each wire should be allowed to handle its max potential, which in this case would be way more than 50 amps for a 2 foot wire to the block. But anyway, 50 amps is pretty much non negotiable for use in the single line near the battery, and wouldn't 50 be fine for the 2 short wires to the block? I'm simply asking because you said no to the other 2 ways and I don't see a third option. I don't even know why I'd need fuses in the block at all if there's fuses on the amps and the wires are so short.

Originally Posted by Maheriano

Seeing that the Rockford amp has a 40 amp fuse, I don't think I even need to go check the MTX. So does that confirm the 8 gauge is no good? I'm like a yo-yo here.

Its simple. If one amp has a 40amp fuse and the other has a 25amp fuse that's 65amps. If 8GA can only handle 52amps for the 15 feet then you need to run 4ga to a distribution block and 8ga from the distribution block to the amp. Put a 75amp fuse up near the battery and your done.

(wired, correct me if I'm wrong) The amps will be pulling a combined 65amps through the 4ga wire. When it hits the distribution block 25amps will travel down one 8ga line to one amp and 40amps will travel down the other 8ga line to the other. If any of the lines break and start to pull more than 75amps combined the fuse near the battery will pop and stop everything, saving your car from a flaming death. Its a really simplified explanation but I think in this case it works and was needed.