DUAL BATTERY SET UP...

[flyguytd]

Hi All,

 

I have a Sierra 2500HD, 6.6 duramax, 4x4. It is my everyday work truck that goes out rain or shine. I am looking to put a dual battery system in the mobile office/darkroom that is on the back. I am running an ac (inverter) and a dc system curently off the start battery. We have been having issues with the trucks computer because of the draw from the original system. I want to put a new system in with dual deep cycle batteries in the back. I know I want to put in a isolator and fusable links in the proper places but I have no idea how big of cable to run to the back and how big (amps) I need to make the fuses, isolators, switches, ect. I would also like to make the new system easy to turn off and on so I do not kill the new deepcycle batteries every time I use the truck and then leave it overnight. Can anyone help me sort through some of this fun stuff???

Thanks

Trevor

[scooby5121]

Check out the older forums about Dual Battery Hook ups

Your questions will be answered there. You buy the kit ...

And when the key is off you would only run off your accessory batteries and when engine runs would charge them....

Engine Battery as you say would be left undrained.

Scooby

 

Battery cables are the same gauge as your booster cable wires or your original equipment is.

[rjromanjr]

What I have read is that you run your isolator off the 4 wheel drive fusible link so that the second battery only engages thru the isolator once the truck is running. check these links out I have done a lot of searching on this topic. Hope it helps.

Jim

 

http://www.gm-trucks.com/forums/topic/68855-how-to-install-dual-batteries/

 

http://www.gmtruckclub.com/forum/showthread.php/19933-How-to-Adding-a-second-battery-to-your-truck#axzz25boewVKr

 

http://www.dfna.info/dual-battery-kit.html

[rjromanjr]

...and if it works out you'll have to tell us what you used and how you did it

Jim

[Red Clay]

You want a min a 1 alternator 3 battery isolator. Rated at least 160 amps as your alternator is 140. The isolator will charge all batteries in the system without letting them draw on each other. Look into coke hershee isolators. As far as your fuses at max 12 inches from the hot post of each battery and the amperage depends on what is the max you will be drawing for you equipment. As far as wire you are looking at 2 awg minimum for the length you are running. Also you need to run they same type and size of batteries in all locations.

[flyguytd]

Thanks guys,

 

So I have figured out a few things. As Red has said an isolator in the system to stop from draining my start batteries is one of the most important things. I have also opted to put in breakers instead of fuses. These to match my isolator in the first system and another beaker off of the coach batteries (here in canada if in an enclosed space it has to be a sealed battery by law). The best result is going to be with 2 x 6 volt batteries in series to get the most bang for your buck. The last thing I am considering in the system (because I am running a DC and an AC system) is a charger inverter the same type of thing they use in a RV. This unit has a few advantages... It is an inverter to power the AC system, it has a low voltage cut off so I don't drain the batteries dead, it is a transfer relay switch which allows me to plug the system into external AC power and it does not blow up the inverter or cook anything else I have plugged in, and it is a battery charger so when I plug in the external AC power it tops up the batteries. All these things would cost a fortune if a guy buys them seperate. It will cost a few bucks to put it all together but when I am done it will be far superior and should stop all the problems I am having with the truck computer and stuff.

Thanks for your help so far guys. If you have any other ideas please let them flow I am still learning

Trevor