help running dual batteries

[Jc12]

Hey guys, i am going to set up a secondary battery in my truck very soon. I like to have a fridge, music, lighting etc when camping so the primary use of the battery will be to power electronics while the vehicle is off. I have done lots of research but am unsure of a few things and parts

i am looking at 2 different isolators (trying to stay in the $50 range)

1. i can get this for $40 new in box, but i am wondering two things, will it have a shut off for my starter battery once it hits a certain voltage or will it only allow for the secondary battery to power electronics? Would this work for my setup?

Amazon.com: PAC PAC-200 200 Amp Power Relay: Car Electronics

2. this is your basic isolator that sells locally

MotoMaster 90A Battery Isolator | Canadian Tire

Now apart from the isolator i am wondering one big dumb question. For the items i want to run off the secondary deep cycle battery, do they need to be connected to it? For example do i need to re route the power for my stereo/interior lights to the secondary battery or will wiring them in parallel and having the isolator allow me to send power to those electronics through the main/starting battery without draining it?

Thanks for the help guys!

 

[Desert36]

I got the stinger 80 amp from amazon... (btw, I have 2 identical batteries)

As for the wiring, ya you have to run everything separate otherwise it will connect both cells together. Only new pita will be a switch that you have to flip for the stereo every time you drive, anything else connected will probably have a switch anyway.

 

[fourwd1]

I use the relay method (#1) in my 83 p/u.
But you have to make sure the relay in your link is rated for continuous duty.
Just because its rated for 200A it doesn't mean the relay is rated for continuous duty.

The isolator (#2) is just 2 heavy duty diodes mounted end-to-end.
And diodes have a voltage drop of about 1V, so if your alternator is only putting the bare
minimum of 13.8V, you batteries won't charge properly.

And yes you'll have to rewire the things you want to run off of the 2nd battery.

 

[Skidmarcx]

I use the relay method (#1) in my 83 p/u.
But you have to make sure the relay in your link is rated for continuous duty.
Just because its rated for 200A it doesn't mean the relay is rated for continuous duty.

The isolator (#2) is just 2 heavy duty diodes mounted end-to-end.
And diodes have a voltage drop of about 1V, so if your alternator is only putting the bare
minimum of 13.8V, you batteries won't charge properly.

And yes you'll have to rewire the things you want to run off of the 2nd battery.

Definitely make sure of this...

 

[Jc12]

okay will do, looks like it is 200 continuous so no problem there. What is the purpose of the fuse boxes people add to the set up. Just organization? thanks


feature -
•Mobile Audio Relay and Battery Isolator
•Great for isolating a second battery making it dedicated to the stereo system
•Does not create a voltage drop to the second battery like conventional isolators
•200 Amps at 12V Continuous Power Handling
•300 Amps Surge Power Handling
•Switching Power: 10 - 16 VDC
•Draws Less Than 1 Amp When On
•Dimensions: 2-11/16" L x 3-5/16" W x 4" H

 

[Mahalas]

http://www.toyota-4runner.org/3rd-gen-t4rs/142289-mahalas-build.html

That's my build, full isolated dual battery. I'm in Burnaby near the New West border. For a couple of cold beers I can answer any questions, draw you schematics and pretty much talk you through the whole process.

 

[blueblur1984]

http://www.toyota-4runner.org/3rd-gen-t4rs/142289-mahalas-build.html

That's my build, full isolated dual battery. I'm in Burnaby near the New West border. For a couple of cold beers I can answer any questions, draw you schematics and pretty much talk you through the whole process.

That is a sweet build! I have a few things on my to do list first but I grabbed most of the stuff from my dual battery set up on my old scout before selling it. I'm itching to get a switchable dual battery set up back in my car.

Need help on a dual battery set up - Binder Planet Forums

**A quick disclaimer. Wiring on an old truck like this is way different a modern car and these photos are from early in the project. There was a lot of trial and error involved before I got a set up that worked!