2nd Battery

[Noobie34]

Hey i am putting in a 2nd battery in my trunk and wanted to make sure i had it right. I have 2 amps the Rockford Fosgate Prime 1200x1 and the Punch p400X4. I have a 200-amp fuse under hood to a block that has a 120 for the 1200 and 60 fuse for the 400. Do i just add another 200 amp fuse before the second battery and run 2 4-gauge power wires off that 1 with 120 fuse and then another with a 60 to those amps? So ill have a 200 amp by my main battery and another 200 amp 12-18 inches before my second battery is that correct?

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[spokey9]

Read a newer book...

 

[djdilliodon!]

As far as grounds go, cars do not operate on AC current and even though AC neutrals will carry half the amperage as the live legs, they are still never fused, the live legs are. Why don’t you need to fuse the neutral/ground? Cause they only carry half the load so if anything is gonna pop it will be on the live legs first. Once it pops that part of the load on the neutral is gone anyway. In a car there is no real reason to fuse a ground just like with AC. You can do it, it will work fine, but it’s honestly a waste of money.

 

[HardofWhoring]

So, couple of things. Not everyone is onboard with fusing the negative terminals, but I do for the following reason. If the stock ground strap from the battery to the body were to come disconnected or get pinched/cut somehow, the amp chassis and ground wire becomes the new ground path back to the battery. First time you try to start the car the amp goes up in smoke, and possibly the wiring as well. The fuse might not save your amp, but it would prevent the wiring from becoming overloaded and starting a fire. Is it rare, maybe but if you are the one... Optional, not everon agrees that you should. As for the rest, here is what I would do. First, when the combined amperage is 300 or less, I use quick acting push button reset breakers like these. They are much fastre acting than fuses.:

Amazon product ASIN B09GXXK11J
Additionally, because I’m running all my grounds back to the battery terminal in the front, I run double the amount for ground. If you are going to chassis ground, no need to do this. You could remove the fuse that you have under the hood and just insert one these breakers in its place and use your existing fuse, in-line prior to the rear battery (as close as is possible) to the rear battery. Then I use a single to double terminal mount on the battery like this one (relative to your battery, post or screw) such as these – use one of the 1/0 receptacles as for the cable you are connecting from the front battery and the remaining receptacle for the next runs run to the 1/0 to dual 4awg block for your amps:

https://www.amazon.com/Amplifiers-Car-Audio-Video-Electronics/b/?ie=UTF8&node=898116&ref_=sv_e_car_7

Or these (the ones I recently used):

Amazon product ASIN B001H4Y5OA
Now you have the batteries connected and fused, ready to go. From the 2nd battery, run a short 1/0, say 12” or whatever works power lead and if you are grounding this in the back too, 1/0 to your ground choice within 18” of the 2nd battery.

Then use one of these from for your power lead to power your amps:

Amazon product ASIN B089CGX68J
Then to a CAP (if you’re using one), then to your amp(s). You can use a grounding block or separate ground leads, 4 gauge or larger to the grounding points you wish to use. I provided this to show the direction and placement of the fusing, you can use ring terminals or other connecting blocks, whatever, as long as the placement mimics this path, you’re good to go.

No that's not how it works. The load for the starter is not part of that circuit. The ground is for the load in the circuit.

You also said you went from your amp ground to batt neg, so it's just a loop, and there is no ground there.

 

[Doxquzme Premium Member]

No that's not how it works. The load for the starter is not part of that circuit. The ground is for the load in the circuit.

You also said you went from your amp ground to batt neg, so it's just a loop, and there is no ground there.

Read the information in that article, it explains it in spades. And yes, I go directly back to the ground, it's worked fine in the past, no issues, nada, zilch. Just like ARC Audio and JL talk about in the article. Their parallel grounding (Amp to chassis/then again from Chassis to battery) it also goes back to the battery. Not sure why you are stuck on the battery being an obstacle, or the grounding point, it’s not. The battery is grounded too, no loop.

 

[HardofWhoring]

Read the information in that article, it explains it in spades. And yes, I go directly back to the ground, it's worked fine in the past, no issues, nada, zilch. Just like ARC Audio and JL talk about in the article. Their parallel grounding (Amp to chassis/then again from Chassis to battery) it also goes back to the battery. Not sure why you are stuck on the battery being an obstacle, or the grounding point, it’s not. The battery is grounded too, no loop.

The battery negative is not ground, and your amp is not grounded because you connect to the battery. Your amps ground is going through the battery negative, and is not grounded until chassis.
Never said the battery was an obstacle. I'll say it again, it's the same ground, it's not the same path to ground. You are adding your amps ground to your batteries ground, and creating added resistance you shouldn't, with no benefit.


If you want to have a discussion about it, then don't just post a link with a long page and a bunch of videos. Use some words, list a video, quote what you are referring to. I'm not going to go hunting through that so that I can have a conversation with myself. One is a forum with at least one person giving bad information. The other one I skimmed through and, none of the highlighted are what you think they are. Neither have anything to do with JL or Arc audio.

Here YOU go, read this:

battery ground - Bing

Intelligent search from Bing makes it easier to quickly find what you’re looking for and rewards you.

www.bing.com

 

[Doxquzme Premium Member]

"The battery negative is not ground, and your amp is not grounded because you connect to the battery. Your amps ground is going through the battery negative, and is not grounded until chassis."

Exactly what I said. Guess there is some confusion on what I said,not going to go all through it again.

"Never said the battery was an obstacle. I'll say it again, it's the same ground, it's not the same path to ground. You are adding your amps ground to your batteries ground, and creating added resistance you shouldn't, with no benefit."

It's terminology, a generalization used to describe what I thought you were trying to express, maybe I misunderstood. Having added (adding to the existing cabling) 2/0 gauge to all the "under the hood" electrical,1/0 from alt to battery (the big three), the resistance added is fine and negated by a very large path to ground. Like I have said, there are valid reasons to do this; I've had great success doing it this way, as have others. As glue becomes as prevalent as welding and metal gets thiiner and plastice get introduced more in the manufacturing techniques, this type of grounding will become more prevalent (just like you have to do in older Corvettes). I feel that the article is very interesting, provides many with greater knowledge, in my book, always a good thing. It’s fairly recent (2021 if I recall) covers a broad spectrum of topics all relevant to this discussion and if you don’t feel like perusing it to glean additional insight, you prerogative. I think that we’ve beat this to death, time to move on.

 

[Doxquzme Premium Member]

 

[Doxquzme Premium Member]

But wait, that can;t be cause there’s no low BASS in rap, right? Or is that only when you are connected to the flux capacitor and grounded to the 100awg wire embedded in your windshield… I’m confused.

 

[Doxquzme Premium Member]

Wrong.

While we have differences in option reagrding speciifc builds and what not, HardofWhoring knows plenty and probably isn't looking for your endorsements! Your explanations are almost never correct. IT ALL FLOWS TO GROUND - IT"S NOT ROCKET SCIENCE!

On top of that, I’ve switched the flux capacitor to run on bio-fuels instead of Uranus fuel - electrons, protons, neutrons and any other “tons” are no longer an issue.