Dual Battery Setup

[57bronco]

I know a number of people running the Hellroaring isolator/combiner and I haven't heard any complaints.

 

[matt w]

http://classicbroncos.com/photos/showphoto.php/photo/26734/cat/500

That's like PERFECT!! ;D

 

[57bronco]

Thanks, it's done me good for over 10 yrs.

 

[bad 68]

OK I have been running dual Optimas wired parallel for over 15 years. I originally wired the second battery to just run the stereo and winch and it was isolated with a diode style isolate that fried twice. Now RRRaaayyy2 correct me if i am wrong. I believe that once you start the engine and the axillary battery is down and the main battery is charged, the main battery and the alt will start dumping into the aux battery. Now, say you drained your aux battery by winching and upon getting the engine fired again you go back to winching and the amperage is more than the isolater can take.
I eliminated the isolator( I tried the factory Ford style continuous duty also) many years ago and have had no problems since.
I don't remember exactly but a Warn #8000 pound winch will draw about 600 amps at stall.
Trust me your winch and starter will have much better performance with 2 batteries suppling double the amperage at the same time.
If you kill both batteries winching your winch will be fried.
If you kill both batteries with the stereo system jamin some tunes and partying, you passed out and good thing you couldn't drive anywhere anyway.
On a camper you never need 500 amps at once. The aux battery trickle discharges maybe 20 amps at a time at most.

 

[matt w]

Thanks, it's done me good for over 10 yrs.

So what are you using for a tray?

 

[57bronco]

I had a piece of scrap 1/4" aluminum, I used for the bottom and a 1/2" X 1" alum. bar for the hold down. The bottom (tray) was mounted where the original went, it is the same size as the two Optimas. I also added some drain holes in the tray.

 

[GrillMaster]

What are the disadvantages of just running a switch?

http://www.amazon.com/6007-Mini-Bat...=sporting-goods&ie=UTF8&qid=1301351634&sr=1-4

I am looking for an easy basic set up.

 

[57bronco]

You will need to run the batt cab to and from the switch. With my setup, I have two toggle switches at arms reach.

 

[57bronco]

There are different setups out there, the one I setup works for me. You may find something that works better for you.

 

[57bronco]

Here are the solenoids.

http://www.allbatterysalesandservice.com/browse.cfm/4,2911.html
http://www.westmarine.com/1/1/24902-continuous-duty-solenoid-12-volt.html

 

[Steve83]

...better performance with 2 batteries suppling double the amperage at the same time.

That's a common misconception. If you had 100 batteries, the starter & winch would get the same amount of current they did with 1 good, charged battery & good wiring. But if you run the winch continuously long enough to need 2 batteries, you're probably overheating the winch motor.

If you want something cheap, simple, safe, & effective, use the Ford system. It works. And you can add a switch to control the relay if you want (say, for jump-starting without opening the hood), but it'll do fine wired directly into any fused key-on circuit (like the gauges).



Note that there's a fusible link wire between the batteries, but I'd use a ~150A circuit breaker.

 

[57bronco]

If you connect the battery's in parallel, voltage stays the same, but you add the amp/hours together and in series you add the voltage together and amp/hours stay the same.

 

[Laker]

OK I have been running dual Optimas wired parallel for over 15 years. I originally wired the second battery to just run the stereo and winch and it was isolated with a diode style isolate that fried twice. Now RRRaaayyy2 correct me if i am wrong. I believe that once you start the engine and the axillary battery is down and the main battery is charged, the main battery and the alt will start dumping into the aux battery. Now, say you drained your aux battery by winching and upon getting the engine fired again you go back to winching and the amperage is more than the isolater can take.
I eliminated the isolator( I tried the factory Ford style continuous duty also) many years ago and have had no problems since.
I don't remember exactly but a Warn #8000 pound winch will draw about 600 amps at stall.
Trust me your winch and starter will have much better performance with 2 batteries suppling double the amperage at the same time.
If you kill both batteries winching your winch will be fried.
If you kill both batteries with the stereo system jamin some tunes and partying, you passed out and good thing you couldn't drive anywhere anyway.
On a camper you never need 500 amps at once. The aux battery trickle discharges maybe 20 amps at a time at most.

Now thats what talking about! Just a knife switch in line ahead of the aux battery to just uncouple it if you want for whatever reason. I was thinking of a fuse too in-line ahead of the aux battery in the event of a short circuit condition on the winch. If drawing 400 to 500 amps at the time the in-line fuse would have to be at least that size or larger or possibly a circuit breaker that would handle the winch load. Thats what I'm thinkin' anyhowz.

 

[57bronco]

Now thats what talking about! Just a knife switch in line ahead of the aux battery to just uncouple it if you want for whatever reason. I was thinking of a fuse too in-line ahead of the aux battery in the event of a short circuit condition on the winch. If drawing 400 to 500 amps at the time the in-line fuse would have to be at least that size or larger or possibly a circuit breaker that would handle the winch load. Thats what I'm thinkin' anyhowz.

Your solenoid pack that comes with the winch will take care of that

 

[Laker]

Ah yes it will 57bronco,thanks for that. Something just popped into my head while I was doing up connections. If I was to run the 12v source wire with a toggle switch from the cab to the solenoid,then I could switch it off without popping the hood. Switch on the solenoid would connect the batteries together when the truck is started and remain on. Switch off the solenoid would not close thus leaving the aux battery disconnected from the alternator. Sound right?

 

[matt w]

So does it matter with this set up if you use an over 10 year old Optima and say another newer battery?

I would hate to mess up my incredible Optima! heh-heh!;D

 

[57bronco]

I rarely run both batt. at the same time, only if both are very low. So one being older shouldn't matter. I think the Hellroaring setup will work too, it automatically switches from one batt. to the other.

 

[RRRAAAYYY2]

I am right in the middle of doing the same to my rig. RRRAAAYYY2 seems to have a lot of technical expertise going there. I would tend to agree with his logic. I too agree with the direct wire between the 2 batteries, but do not understand how a solenoid would keep the batteries from working or charging in unison. Once the contact is closed the current will flow equally back and forth between both batteries. I can see how the difference in battery voltage and resistance will affect the charging of each battery, but is it noticeable?
I have a brand new battery on the auxiliary side and the main battery is who knows how old? It came with the truck when I got it a year and a half ago.
My concern would be will the new battery crap out prematurally if their direct connected together? What say you RRRAAAYYY2?I will post pics of my set-up here as soon as I wire them together

There is a natural voltage drop threough the contacts of tthe solenoid, so when the alternator reads the system, one battery will be giving misinformation, i.e. read below its true voltage.

 

[RRRAAAYYY2]

OK I have been running dual Optimas wired parallel for over 15 years. I originally wired the second battery to just run the stereo and winch and it was isolated with a diode style isolate that fried twice. Now RRRaaayyy2 correct me if i am wrong. I believe that once you start the engine and the axillary battery is down and the main battery is charged, the main battery and the alt will start dumping into the aux battery. Now, say you drained your aux battery by winching and upon getting the engine fired again you go back to winching and the amperage is more than the isolater can take.
I eliminated the isolator( I tried the factory Ford style continuous duty also) many years ago and have had no problems since.
I don't remember exactly but a Warn #8000 pound winch will draw about 600 amps at stall.
Trust me your winch and starter will have much better performance with 2 batteries suppling double the amperage at the same time.
If you kill both batteries winching your winch will be fried.
If you kill both batteries with the stereo system jamin some tunes and partying, you passed out and good thing you couldn't drive anywhere anyway.
On a camper you never need 500 amps at once. The aux battery trickle discharges maybe 20 amps at a time at most.

The isolator simpily gives the current two places to go, main battery or aux battery. It cannot control when, how much, etc. The batteries will just absorb what they want. I think the reason why they dont fry as quickly wired like that, is they are a typically a greater distance apart. Under the hood, and in the trunk kind of thing.

 

[RRRAAAYYY2]

Here are the solenoids.

http://www.allbatterysalesandservice.com/browse.cfm/4,2911.html
http://www.westmarine.com/1/1/24902-continuous-duty-solenoid-12-volt.html

They are only continous duty, for which the duty cycle is 60 seconds, vs intermittent duty, which is 10 seconds. There is a continous duty prolonged on solenoid, that is available for use in applications over 60 seconds.