posted
i have now decided on a second battery for my car (don't know why, will eventually upgrade my alt). now how do i wire this thing up, so that when the engine is off, the secondary (in the trunk, with amps) battery won't draw current from the main battery and kill it. here is an interesting isolator i found, http://www.hellroaring.com there was also talk in another post about two batterys split current or something thus causeing the alt to need to create only half the current but for twice as long (something to do with when extra current is needed). please be very detailed, what wire goes to what terminal, where. most of my cabling will be 1/0awg or 2/0awg, and the common ground from the alt and main batt will be upgraded to this. main batt to starter, and alt will also be upgraded. i think there only 8awg or 4awg right now.
posted
Installing a second batt is very simple. First off I would never use an isolator, there is always a V drop across them and they are ususally $$$. Use a selenoid, just go down to your local alt/batt shop and ask for an AC delco continuous duty selenoid. It will run you a whopping 25$ maybe. This sel is basically a big relay. It will go inline (just like a fuse holder etc) on the main power wire in your car that will run from + on the front batt and + on the rear. The selenoid will have a "trigger" terminal which you simply provide with "ignition" power. This way when the engine is running the sel will be closed and the rear batteries charging. And when you turn the car off the sel will open and the amps will draw from only the rear batts. A minimum!! of 4guage cable should be used form front to rear batteries. Larger is of course better. Especially with a high output alt.
------------------ Knowledge=SPL As does and open mind Team Hertz Canada Pres Hertz Audio
Posts: 221 | From: Calgary, AB | Registered: Nov 1999
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posted
k, so i leave everything hooked up the way it is. alt to main batt, starter ect. just ungrade the factory cables all around. then i run a big fatty from the main batt's Positive (like i would have to run my amps using only the single battery), back to where ever i put the big Solinoid, from there back to my deep-cycle batt. now do i ground the deep-cycle to the car. if so should i ground everthing back there (amps, processors, deep-cycle batt) to the same point, or us seperate points for all of them. do i run the amps positive from the batteries positive.
i would do trial and error like i usually do, but i like my stereo equipment. it's not like the other stuff i've retro'ed, and eventually set ablaze. electrical fires are fun, but not when you've got money invested in whatever's one fire. plus the fire department starts to wonder why so much stuff catches fire when your around.
posted
I usually put the selenoid in the front under the hood, its easier you get key on power from there. Other than that you seem to have it right, use the same ground point for everything trying to keep your grounds less than 2feet long.
------------------ Knowledge=SPL As does and open mind Team Hertz Canada Pres Hertz Audio
Posts: 221 | From: Calgary, AB | Registered: Nov 1999
| IP: Logged |
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