Installing a battery isolator

I have an air nautique and i want to install a second battery with an isolotar. HOW? what goes where?

This Isolator is an automatic one.
Positive leads of both batteries and a lead
from the alternator is all that it needs.
It will automatically decide which battery
needs charging so the weakest gets the alternator's full capacity. This unit
will also separate the batteries so that if
you are running accessories only one battery
will be used saving the fully charged battery for
starting. My favorite thing about this is it eliminates mistakes made by the operator. I can't
tell you how many times I left my manual switch
on two batteries wanting them both to charge
while the engine was running, only to run them
both down with the radio because I forgot to change back to a single battery.

http://ww2.boatus-store.com/images/full/224025.jpg

You should also look at the Hellroaring isolator combiners. They do not have the voltage drop that diode isolators have. The voltage drop can cause premature battery failure due to incomplete charging. They are more expensive ($140) See their page for tons of info. www.hellroaring.com I am going to install one and write an article about it soon, my boat comes home today You can also use a heavy duty relay to connect/disconnect batteries when the engine is running, that is the cheapest method.

Hey Dom Check this Out
http://www.geocities.com/mtbmudmachine/stereo.html

So the pos. lead that runs the accessories wires directly to the designated house battery, or in my case battery 2 ??

And the pos. lead that runs straight to the starter goes on the isolator??

the positive side of each battery will have 2 wires after this....one for what its dedicated to (either starter or house) and a new wire that runs to the positive terminal of the isolator. the isolator completes the loop making it all connected.

you'll also have to ground the isolator into your existing system.

the last new wire goes to the alternator to activate the isolator when you turn the key on. you should locate a wire on the alternator that's only activated by the key switch. without this, you'll just drain the batteries and never recharge them. there's a spot on the isolator for this wire.

check this diagram:
http://www.stingerelectronics.com/sting_products/sr200_sr80%20diagram.pdf

you would be better off to use a perko switch,we have had problems with Isolaters on boats ,seem to screw up the regulaters for some reason.

Psyclone, You are my hero!!

I have a Hellroaring unit that I picked up last year. Have yet to install it. I even have the mico switch with enough wire to go from my battery location to under the driver's dash.

I would love to see you article once completed. I've just been very lazy and not put mine it. I know it's not that big of task, but things like riding and putting in stereo equipment keep getting in the way!!! Plus I carry a charged portible jump start pack with.

I'd have to say that Hellroaring provided me some top quality customer service. Super helpful and have a great product!!

(Message edited by magic on February 28, 2003)

Dang Sean, You're my hero. Anyone who has the balls to do an invert on an Air Chair is a hero to me!
I may start tomorrow, part of the job will be cleaning up my stereo installation. The isolator should be no big deal, the hard part is figuring out where to locate things and not drilling holes through the hull!
I'm going to use their "basic auxiliary battery isolation" which won't really provide two batteries in parallel for starting, but will isolate the starting battery from the Optima I'll use to run the stereo. You can flip a switch and charge the starting battery from the aux in 15 min, but I carry one of those jumper packs too!

Ok, so what is the difference between a combiner and an isolator? And which one is more effective? This is confusing.

I started to write a long diatribe, but you should look at the Hellroaring page for a better explanation than I could give. The hellroaring isolator combiner is basically an isolator using solid state relays. It is automatic, and it has all the advantages of isolators and relays, and none of the drawbacks. Typical diode isolators drop 1.4VDC, so your batteries never fully charge. It doesn't sound like much, but that is 10%. Mechanical isolators like relays and Perko switches have their own issues, and it is not good to just put two batteries in parallel unless they are the same model and age. Take a look at the page, look at the automotive setups for deep cycle batteries for audio, they relate more to what we are all doing with our boats. The marine setups shown are more for trolling motors and starting battery isolation for offshore boats and stuff. The simplest (aux battery isolation) setup is what I am going to do to my boat.

Here are a couple of pictures of my installation, still ongoing. The Hellroaring unit is more complex to install than other isolators, but it drops less voltage so your batteries don't sulfate from constant undercharge.


I located everything on the back of a panel in my storage compartment. I have an 8 gauge wire coming from my existing Perko (charge source) and a larger 4 gauge ground going to my starting battery. There are two 6 gauge wires going to my amp. There are two large fuses, one for the isolated charge source, one for the amp. One little fuse for the isolator.

Don't commence to giving me sheot about the wire sizes, they are all according to this guys' explicit instructions. The input wire from the alternator is supposed to be 8 ga. to limit current from the starting battery. The deep cell Optima supplies my amp only. One of the nice features of this isolator/combiner is the remote LED that can be used to diagnose charge/battery problems. I wanted to keep everything in one place so I mounted a LED in the front of the panel. The black blob in the above picture is five minute epoxy that I used to secure the LED. I used a different one than is supplied with the remote module kit. I'll have to stuck my head in the storage compartment to see it, but that's ok, I keep extra beer in there.

Psyclone, what are those two red boxes next to the isolator?? Fuses?

When you get done, could you elaborate on where the wire goes from the isolator to the alt?

Thanks.

(Message edited by sdub on March 05, 2003)

They are 50 and 60 amp fuses. I would have rather used breakers but I already had one fuse holder. The one on the left is for the amp, the one on the right is for the Aux side of the isolator. If you look at the isolator, there are two large terminal lugs. The one on the right has a 6 gauge wire going to the aux deep cell. The one on the left has a ring connector but no wire. That is where the 8 gauge wire from the existing battery (charge source) will go.