How can i do a dual battery setup? (cheep)

[deek]

The cables & mounting really don't concern me. I'm just wondering how i should configure the wiring. I have two remote mount starter silinoids that could be used for switches.
I want them to charge together but I don't want one to drain off the other if one goes bad, & if i had to run one dead say because of a winch, I want the other one to still be charged to start the blaze. I'm open to any ideas aslong as its cheep

 

[84_Chevy_K10]

 

[bablazer73]

Thats about all i did. i have a dual battery switch from an ambulance, batt 1, batt 2, both, off.

 

[gravdigr]

[ QUOTE ]

[/ QUOTE ]

Won't work because of:

[ QUOTE ]
I don't want one to drain off the other if one goes bad, & if i had to run one dead say because of a winch, I want the other one to still be charged to start the blaze

[/ QUOTE ]

Run the heavy cable from the aux battery to 1 of your solenoids then out of that solenoid to the positive on your main battery. Control that solenoid with a toggle switch. Run a wire from the alternater to your other solenoid then out of that solenoid to the aux battery. Control that solenoid with the ignition so it is on when the vehicle is on. You may also want to install a manual toggle switch between the solenoid and the alternater. You would turn this switch off when winching because if the aux battery goes dead it will try to pull power through the thin charging wire from your main battery. To avoid that you could close the solenoid between the batteries and use both to winch but that kinda defeats the purpose.

Now keep in mind that if you are using normal starting solenoids they will probably burn out in a short time. You need a constant duty rated solenoid.

 

[deek]

GravDigr:

what side do i take the Alt. wire to (+ or -)?
& do i just connect the - terminals to each other, or just ground out the Aux. Batt to the frame?

 

[gravdigr]

the charging wire from the alternater goes to the + on the aux battery. Ground the aux battery to the frame and body. Also it may be a good idea to run a ground strap from the engine to the frame.

 

[gravdigr]

I got creative with paint and made this diagram...

The blue lines indicate factory wiring. Basically you keep switch 1 closed until you put a heavy strain on the aux battery such as winching. Switch 2 stays open until you need the aux battery to actually run your vehicle. Then the aux battery will start your vehicle and provide power until you get home. Hope that helps.

 

[big83chevy4x4]

go to a marine shop and pick up a dual batery switch. mine was about $25 /forums/images/graemlins/waytogo.gif all you have to do is run both positives to the switch and then one to the starter