Adding a 2nd battery to a Tristar

[js9467]

I've got an Optima Blue top powering the stereo system and a plain ole Autozone deep cycle for everything else. No issues here.

[quincyfirefighter]

You should look at long time member Diesel's battery set up. I did this also and love it. The thread is called the official dual battery thread. You don't have to mess with a perko switch.

[pbgbottle]

i did mine like this also .but i put my second battery in the rear back corner shoved it in the side ski locker there is an upper shelf in the rear back corner and mounted my switch in the rear, the stock wires where long enough .
to reach the switch , only thing i did wrong was use the wrong battery tray now i cant slide the battery back out .

if i need to access it i can go in through the side intake vent if need be. . the little post sticking out the side of the battery is for charging it .
pics below.

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Originally Posted by MLA

Lee,

Sorry, not calling you "Stud" ok . Electrically, its not a major upgrade to do. The trick is to find a good spot to mount the switch without having to extend the original B+ cable.

Every cable thats currently connected to the original battery's B+ post, except the auto-bilge wire, gets relocated to the "C" post of the dual-battery switch. The bilge wire is typically brown w/red strip.

With a new cable, the GND post of the new "house" battery gets run to the GND post of the existing battery's GND post.

With a new cable, the existing "cracking" battery's B+ post gets connected to the switch post "1".

With a new cable, the new "house" battery's B+ post gets connected to the switch post "2".

I typically use 1/0 gauge cable for these connections, since you will most likely use the new house battery as a secondary starting battery at some point.

Your amp's B+ cable will now be routed to the switch's "C". This is done for a couple of reasons. 1) we want ALL of the stereo gear to share the same battery source to prevent unwanted noise, and 2) this allows the stereo to draw off which ever battery we have the switch turned to. When anchored, you will be running of the deep-cycle in position "2", leaving the main cranking battery isolated and in reserve. Once running again, the switch can be returned to the "2" position to replenish the house a little.