12 Voltguy Dual Battery wiring help...

[Keitha]

The picture is from the 12 voltguy instructions for the dual battery set-up.
The "Main Battery" is a Red top and I want it to ONLY go to the starter and disconnect at ignition off (alternator off).

2nd Battery is a Yellow top and goes to all other 12 volt in the car including stereo, lights, accesories, etc.

My logic is that if I ever leave something on - door open, light on, stereo on..., the red top "main battery" should always be good to go.

The instructions do not at all tell me how or where to hook the alternator up.

Any advise?
Am I going about this correctly?

thanks,

 

[Fordum]

OK, here is what to do.
I personally don't like that arraignment, but most everybody else does, so I'm fine with it.
It works, thats the bottom line.

When you fire the big relay, it hooks both batteries together, so they can both charge. Plus, one will jump the other off if needs be.

So, just hook the alternator to the 2nd battery. When the relay is off, the batteries are separated, so you cannot run down the main battery, and when the engine is running, the alternator charges both.

J.