Hey there all,

I am piecing together my dual battery setup and have come to the conclusion that I am wanting to go ahead and purchase full wiring kits as provided by sierra expedition.

So far I have:

1 red top optima (for when my current battery dies any day now)
1 2X battery tray from Ruff Stuff

and now it is time for wiring...

So:

a) National Luna DIY - Split Charge System

b) IBS -DBS Dual Battery System with Microprocessor - Sierra Expeditions

Both will do what I want, however, B. seems like a smaller underhood package as I am maxed out due to extensive wiring relays for lights and solenoids for winch. A. says it has 3X the wiring so I can upgrade all leads at the same time, but that "smart solenoid" looks monsterous...

Any advice? Seems like all the 5th gen guys are going with the IBS... 3rd gen'rs ring in?

Thanks,

I'm using a Blue Sea 7622 ACR with my set-up.....not much help, am I?

Either system will do a good job, but they are both probably overkill (and overpriced) if you know enough about electricity to make your own. Do some research and save $200.

Blue Sea Systems has some good battery isolation systems starting at about $100. They are made for boats, which usually have dual battery systems (house and starting/engine), and they are made for very harsh environments.

https://www.bluesea.com/

Here's a link to several different products: https://www.bluesea.com/products/cat...harging_Relays


Also, some good info on this thread: How to make a cheap isolated dual-battery setup for $50 - Expedition Portal

The parent thread has lots of threads about this sort of thing, from guys who use them a lot.

Power Systems: 12v, Solar, Gen. - Expedition Portal

blue sea 7622 w/ gammatronix battery monitor LEDs.

HOLY SCHAMOLY!

That crap is expensive. OK, the two previous replies were good replies. Both of those posters know I have to give my .02. FWIW

I'm not saying cheaper is better, but I believe for that money you could build a better system that will last forever.

I am old fashioned, for a technogeek. Give me an analog Voltmeter anyday, in lieu of that, I'll take a digital voltmeter. Keep the LEDs some where else.

But the real problems come in the "intelligent" solenoid. As noted Blue Sea has some nice stuff, but they too require a deep Blue Sea pocket. Still I know their products and I like their products. Definitely a good option.

Did I mention that since Interstate bought Optima they suck. Yeah, I killed about 8 of them before I gave up. Odyssey style are pricey, but they work, more than I can say for Optima.

Back to the solenoid. In my L/C, I use a $30 golf cart style continuous duty solenoid. Similar to this one.

Amazon.com: NEW 12V 150A CONTINUOUS DUTY SOLENOID FITS RELAY FOR GOLF CARTS 1114208: Automotive

I've had the same solenoid for about 6 sets of batteries, probably 12 to 15 years. @98OzarksRunner taught me that the Blue sea ACR has the added feature of a delay, useful for dead battery moments. You can always add the Intellitec delay, or even use their Solenoid, which is used in a few hundred thousand motorhomes all over the world.

http://www.intellitec.com/assets/pdf...-00629-120.pdf

I think the Blue Sea might edge the Intellitec in price, when you add the cost of the delay.

NEXT problem, battery cables. I can't tell what you are getting in those kits, but I much prefer to get my own 2/0 or just O cable and buy the ends in the sizes I want. Which makes an important point. The quality of the terminations is the most important part of the dual battery set up. Crimped and Soldered ends are the way to go here. My solenoid is as old as my cables, do the math, just sayin'.

Or you could just buy one of those and let me know how it's working in 12 years.

<---Always wanted to use that

OK, great info from everyone.

IBALL- (forgive my understanding, or lack of) the isolator works only when the key is on, engine off to run off of house battery. Am I correct in assuming that engine on runs/charges both batteries all the time? Thereby constantly linking them while running with no way to hard link them in case of needing both batteries with the engine off? (Without jumper cables) AND no way to isolate starting battery from a dead house battery while cranking?

Sorry, I'm trying to make sense of this. Cheaper IS better as long as I'm not sacrificing capability.

Even if I go Bluesea 7622, I'm looking at a minimum of $300 in the unit, cables, ends and fuses... Not far off from the IBS LED remote pad selector... Just a thought.

Am I missing what Ozark, Habanero and Brilliant are discussing?
This the right one? Amazon.com : Blue Sea Systems ML-ACR 12V DC 500A Automatic Charging Relay with Manual Control : Boating Battery Switches : Automotive

Thanks guys for all the input. It seems that a manual selector for the link of the two would be important and isolation cranking ... Steer me if I'm wrong.

Well that is a mighty fine(expensive)ACR. I would love to have it, but I wouldn't buy it.

The full manual is nice, but not worth the extra money in my view. That one is better suited to multiple battery setups like a Boat or RV would have.

This $69 one would be just fine. And you could wire it to a switch, or switches for a semi-manual operation. This way you could link them with the engine off, and you could choose which battery to use.

https://www.bluesea.com/products/760..._12_24V_DC_65A

I do this in my L/C with the $30 solenoid and a $10 switch. On the above link you can find the "instructions" link to a pdf file that shows the ignition source activating the solenoid. All you need to do is tap that circuit for what you want.

The benefit of a "kit" is that someone thought it out for you. The negative is there is no way to make a one size fits all and the quality level suffers. I'm a lazy cantankerous bastid, or I'd make you a list with prices that would be LESS than $300 and far better than either of those kits. YOU are on the right track, study a little more, ask good questions like you are and you'll be happier with what you build.

I got the 7622 because it was the cheapest auto linker out there with a remote switch and manual override. Seemed most features.

I did theled because I wanted stealth install. My build has some info on what I did. You can also get a few dollar display. Anything to avoid a massive Luna panel claptrap.

As to cables, you'll need a hydraulic crimper. Soldering isn't they way to go and complete unnessicary with a proper crimp. EBay sells 10ton crimpers to crimp heavy guage.

Good luck, oh and odyssy are the way to go. I'd look at Columbia overland 1700 dual over the ruff stuff one. I went alarge small starter, a different setup, but works well for me.

X2 on the LUNA, it's just ugly.

I've studied crimp vs solder for many years. And you are correct, properly crimped the solder is not absolutely necessary. But properly soldered, a crimp is not necessary either. I recommend soldering for two reasons.

The economy crimpers are OK, but not great, and the crimped copper lug looks ugly. I know, I have a lot of those on my truck and I cringe everytime I look at them. But they work just fine.

The second reason is I believe people in general pay more attention to how they solder then how they crimp. And using solder terminals and solder pellets, they look damn good.

Here is a youtube video about crimping and soldering.

https://www.youtube.com/watch?v=HQbJO6mnIyc

Either way can be done correctly!

Maybe it's preference then. I prefer the crimp because I've had better luck with the mechanical connection. It's also easier to do on the vehicle from my experience.

After going through all of the options that you guys have graciously posted, I will likely go with the 7622.

This all could be done much more simply and cheaply, however, I want to maintain my isolation on start and selectable pairing.

Since I will be rewiring, I plan on redoing all of my "big 3" Grounds as well as some leads to my alternator and main/auxillary fuse box. Maybe overkill on replacement, but should be a nice clean upgrade. Installs for other people may be cheaper if you don't do this or have already.

Blue Sea 7622,
30' of 2AWG
10 X copper lugs
4 X terminals and covers
crimper
shrink tubing

all runs about $310 on amazon.

I figure that I don't really need voltmeters as kitted from sierra as a built and tested system should take care of the charging. Maybe some 80 amp fuses will be put in line once I get the diagrams from Blue Sea... We will see.

-Brilliant, already got 1 optima and the ruff stuff cage so we will continue down that path... Thanks for weighing in

Appreciate everyone's idea...

30' of 2awg?? haha you wiring up 3 cars?

I have a yellow top in the back left of engine bay and one in the front right. I use prob 6ft . Then just have the blue sea in between the two and just put the switch in the hood. mainly keep it on auto.

You dont need 2awg for big 3. 4awg be plenty and then its only maybe 9ft max extra. So your looking at 15'. I know wire is prob a large cost in you estimate. the diff from 2 / 4 is insane.

Do the alternator + to batt in 2awg and the Batt grounds to frame and engine in 4awg(both batt) since it will be so redundant if your so worried about cost
Check out your local radio shop or welding shop for wire, might be a little cheaper.

ha, point taken. Good catch,

It's not too much more for the extra bit. I'll dial it back in length, but the gauge I think I may stay true on. less than $50 for 30' of 2AWG. I went to my local TSC for my winch lead cables and got into that for I wanna say $80.

So I thought I found a deal... might be able to knock $10 by dropping in length and maybe another $5 by dropping gauge... Would be nice to have new starter lead as well...

Thanks for chiming in,

that thread you shared is great!

I'm confused about one piece though.
the specs say to wire a 12G wire to a fuse existing in the rig that is only hot when engine is running. Anyone have details on wiring this? I'm unclear on how to connect the 12G wire to an existing fuse.

Thanks