2nd Battery Question

[the727kid 10+ year member]

I'm not quite sure what you mean, could you explain a little more please.

 

[audiolife 5,000+ posts]

the end that is screwed to the car (the ground ) unhook it from the car . hook up another 0 ga wire to the neg post up front run the wire from there to back by where the ground cable is now loose . you can crimp another oring to the new wire and screw them together or you can take the oring off and use a coupler. you want to insulate the coupler or the 2 orings just to be safe. then see if the alt charges the back battery good with the sound system off. should start to go up after a few minutes and hold the charge

 

[the727kid 10+ year member]

Alright I understand. Will have to go try that after xmas.

 

[audiolife 5,000+ posts]

if it works good then change it over the right way so make sure you leave enough wire left over so you dont go wasteing a run of wire that is almost long enough

 

[the727kid 10+ year member]

Could I just measure the resistance of the grounding point on the main battery to the grounding point in the trunk? Because in order to do what you said I need to buy 15ft of 0 gauge.

 

[expo5.0 10+ year member]

you can do it with a dmm and a little creativity- yeah

 

[audiolife 5,000+ posts]

i have also heard that even with the same potential that with the ground being at a different location that it acts as if the rear ground is in a different circuit, because its not grounded to the frame. never really thought about it i just knew that if it didnt work in the back just do everything at the battery

 

[Team Hammer 10+ year member]

If your alt is a 140amp adding a second battery will not help. The charging system must be able to charge at the same rate that power is being consumed.

Also your wiring from the alt must be sized to meet the new demands. A 10ga wire is not going to cut it. I run a 1/0 for power and ran a 1/0 ground from mine.

 

[expo5.0 10+ year member]

only needs to charge at an average rate which is greater than the rate at which power is being consumed on average.

if you keep the volume down overall but play it loud for short periods of time a 140 amp alt can "support" 10k rms with enough batteries

 

[Team Hammer 10+ year member]

only needs to charge at an average rate which is greater than the rate at which power is being consumed on average.
if you keep the volume down overall but play it loud for short periods of time a 140 amp alt can "support" 10k rms with enough batteries

You mean Watts being consumed not volume being turned down. Remember a Watt is a Watt!

That 140amp alt only has a 30amp overhead to run all the add on stuff. HU, Amps, Lights etc...

When you crank it up the alt is going to running your system and has nothing left for charging your battery. It's at this point your car is running off the battery now.

10k watts is 695 amps at 14.4 volts, you better have a 400 amp bttery charger in your trunk!

 

[the727kid 10+ year member]

If your alt is a 140amp adding a second battery will not help. The charging system must be able to charge at the same rate that power is being consumed.
Also your wiring from the alt must be sized to meet the new demands. A 10ga wire is not going to cut it. I run a 1/0 for power and ran a 1/0 ground from mine.

My big 3 was done months ago lol.

 

[audiolife 5,000+ posts]

i also dont get it why do people think everyone that gets a 2000 watt system cranks it up all the time?

 

[the727kid 10+ year member]

i also dont get it why do people think everyone that gets a 2000 watt system cranks it up all the time?

I do most of the time except when I'm on the phone or in neighborhoods or on my way to the mall.

 

[the727kid 10+ year member]

I MAY have found the problem....I went and removed the back panel and stuck my hand down by the battery to see if anything was loose and the ground was completely disconnected....

 

[audiolife 5,000+ posts]

that will do it lol