Battery Planning

Ramblinman

Senior Member
Joined
Aug 26, 2011
Messages
506
Location
Alberta, Canada
Putting a 2010 Hawk on a 1998 Chev 1/2 Ton- Camper has Furnace, 3 way Fridge, and incandescent lighting which I will likely change to LED replacement bulbs. I have room for an auxiliary batt under the hood. The Hawk will likely get lots of use in the early spring and late fall (Excessive Furnace use?) The Camper came with a the factory battery. I would like to get maximal use out of the aux under the hood and of course the battery in the camper. The first battery would obviously be dedicated to starting the truck, but I would like the aux to act as a reserve to boost the main truck battery.

Can anyone offer some suggestions as to how I should set up the three batteries.

Thanks!
 
Dedicate 2 to the camper and never pull off the truck battery for camping. Then the chances of having a low starting battery more or less go away unless your starter battery just happens to be wearing out on it's own. In which case if you need to give it a boost and have juice in your camper batteries just use a set of jumper cables. Obviously replace your starting battery after this if it's wearing out (and you didn't just accidentally leave a light on or something).
 
Putting a 2010 Hawk on a 1998 Chev 1/2 Ton- Camper has Furnace, 3 way Fridge, and incandescent lighting which I will likely change to LED replacement bulbs. I have room for an auxiliary batt under the hood. The Hawk will likely get lots of use in the early spring and late fall (Excessive Furnace use?) The Camper came with a the factory battery. I would like to get maximal use out of the aux under the hood and of course the battery in the camper. The first battery would obviously be dedicated to starting the truck, but I would like the aux to act as a reserve to boost the main truck battery.

Can anyone offer some suggestions as to how I should set up the three batteries.

Thanks!

I assume that the aux battery in the camper is located in the storage compartment under either the side couch or dinette. I am not sure about the side couch, I have the dinette and I was able to fit 2 Lifeline GPL-31T 13"L X 6 3/4"W X 9 1/4"H in battery cases in the aux battery storage compartment, made it easy to parallel. Forgot which brand battery that FWC installs, but I know it was up in the 8o amp range. In your case the factory battery is only a year old with plenty of life left, you probaly don't want replace it. Parallel would not be a good idea. Your option would be to switch cables over to the second battery, or use a switch better yet. If you keep it in the truck you will have to run the cables under the chasis back to the camper.
 
Dedicate 2 to the camper and never pull off the truck battery for camping. Then the chances of having a low starting battery more or less go away unless your starter battery just happens to be wearing out on it's own. In which case if you need to give it a boost and have juice in your camper batteries just use a set of jumper cables. Obviously replace your starting battery after this if it's wearing out (and you didn't just accidentally leave a light on or something).

I installed a battery interruper toggle switch next to the starting battery and switch it off when I stop to camp. Since your Hawk is a 2010 I would thank that since you have the factory aux battery that you also have the IBS-DBR also installed, I installed a battery interruper toggle switch on the manual link connection and if you need the extra boost to start your truck you just switch it on and you are able to use both of your aux batteries to start your truck. When I first forgot to switch off my starting battery and left my porch light on all night, my starting battery which was close to the end of its life from old age was dead. Was I glad I had that IBS-DBR linked, After 3 1/2 days of running exclusively off my camper battery bank I had plenty of juice to start my truck. Of course I had the 2 Lifelines in parallel for a combined 200amps. I have replaced the old battery, but I still switch it off just in case, you never know.
 
More likely than not the wiring between your main and aux batteries is not sufficient to provide high amps to help boost the starter safely. If you need the boost just use some jumper cables.
 
What I would do is use an ACR/VSR to combine all of the batteries when the engine is running and the alternator is charging. Put the underhood aux. battery and the camper battery in parallel. The point made about wanting those two batteries to be the same is a good one. The wiring between them will want to be fairly large, larger than max charging current at low voltage drop would call for so as to minimize any resistance between the batteries. Ground both of these batteries to the same bolt. Anything else or too small of a wire between them will set up a self-discharge.
Both of the aux batteries in the camper is really the better way to go.

How to separate out the camper battery from the aux battery during a self jump-start is the crucial issue. If you can find a Normally Closed relay/solenoid capable of a little more than max charging current then set it up to switch open during starting. That will automatically take it out of the system during every start, not just when self jump-starting. Whether you hard wire the self jump-start mode or use jumper cables is up to you. I can see advantages in both. If you wouldn't normally carry jumper cables then hard-wired using a marine battery switch is probably the way to go.
 
If you wouldn't normally carry jumper cables


Any self respecting traveler should have cables. :p
 
Any self respecting traveler should have cables. :p

Just covering all the options.
I carry a very small set of GM sold jumpers, the wire is only 8ga., in my race/chase tool kit. Someday they may not be enough, but they have been for the last ~10 years. Usually only need enough amps from the jumping battery to keep the volts up enough for the electronics to function while cranking. Used to carry a more typical set, but they were bulky and always a mess. When not dealing with a full size this becomes an issue rather fast.
 
Throw'm under a seat and forget about them. ;) I'd carry jumper cables over a host of other gear.
 
That's just it, they don't FIT under any of my seats. In my case we are NOT talking about a full size truck.

And like I said, I was only covering the options that I could envision.
Personally I prefer to have a marine switch in parallel with an ACR/VSR. Gives me charging and starting redundancy in a simple system. Call always fall back to using jumper cables if multiple failures happen.
 
Any self respecting traveler should have cables. :p



I've pulled mine out several times for fellow campers and travelers. Even jumped a semi, have also used my air compressor to pump up others tires and my jack to help change tires.
 
That's just it, they don't FIT under any of my seats. In my case we are NOT talking about a full size truck.


Do you have something mounted under your passenger seat?
 
Thanks! I am learning lots here.

What I am thinking (please correct me if I am going down the wrong road) is a regular good quality battery as the vehicle main starting, a deep cycle that can be used for my winch and my camper, and the battery that came with the camper (Deka 79 Amp I think as I have paid for but not picked up the camper yet) as a reserve battery. The Aux deep cycle would be the battery that I use to power the camper most of the time, The 79 under the couch would be used as back up and would be a clue to start charging the deep cycle if it got too low. I would like to hook them all up with switches so that they would take a charge from the Alternator and the Shore power, but the Aux/and Deka would be drawn from separately while using the camper. Clear as mud?

Can I make this work?
 
Do you have something mounted under your passenger seat?

Not mounted, but it is stuffed too. I've had 13 years with this truck to work out how & where to pack things. Refine and condense, refine and condense, etc. The race/chase tool bag goes with me on any trip, so I do have the small jumpers along, but in an '84 Toyota there just isn't the room the full sizes have.



Ramblin',
Winching is a lot more like starting so any battery intended to see winch loads should probably be a starting type battery rather than a deep cycle type battery. Not that a deep cycle won't run a winch (been done a lot), but that relatively short bursts of high current is what a winch wants and what a starting battery can best supply. If you foresee that you'll be winching with any regularity I think the starting battery is the better choice to connect it to.

I also think that the battery in the camper should remain the primary camper battery. That allows the aux battery under the hood to be the back-up for both starting and for the camper without having to run large, starting current capacity battery cables to the camper.

The thing about marine switches is that they don't switch themselves. If you are absolutely anal about checking and setting such things then you could build the system using only manual switches. If you are like me and not consistently anal enough about such things then I would suggest looking into the Automatic Charge Relays / Voltage Sensing Relays as these do the switching for you based on if the alternator is putting out voltage or not. Can easily wire these in parallel with a marine manual switch so that you have redundancy and self jump-start capability. I know that BEP Marine offers just such a combo package and I think that Blue Seas does as well.

The issue becomes separating all three batteries. Two is easy, 3 can be a little more involved to a lot more involved depending on where you want to control this from and how.
One method would be to use the VSR/switch linked above to charge the under-hood aux battery and the camper battery. Then in the wire between the under-hood aux. and the camper batteries have a Cole-Hersee constant duty solenoid activated by the ign switch in run mode. In parallel with the solenoid have an manual switch. This way the two aux batteries are combined with the ign on and the VSR takes over making sure that they're charged.
Turning off the ign disconnects both the VSR and the solenoid, so now each battery is isolated from the others. Turning on either manual switch will connect the two batteries immediately on either side of it together. You would need to either run very large cable to the camper battery or be Extremely careful to never try to start the engine with both manual switches turned on. A safety that could be installed would be to put a large amp Maxi fuse (or similar) somewhere between the under-hood battery and the camper battery. Size it and the wire or cable to be safe with maximum alternator output, plus a little extra for a margin. With the fuse in the system should you try to start with all of the manual switches turned on the fuse will blow if more current than the wire or cable can handle is demanded from the camper battery.

The more that I think on it, this is how I would set it up if I did not simply make both batteries under the hood into a single battery bank.
 

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