House Battery for Electronics

[Tidedancer]

House Battery for Electronics
I have a single motor with a 2 battery set up (#1, #2 and both) I run mostly on the #1 battery. I am having a problem with the cart-plotter and bottom machine going off when starting.
I am thinking of adding a 3rd battery as a house battery just for the plotter and bottom machine. I have a two bank charger on the batteries already in the boat.
My question is. Can I run the plotter and bottom machine on a 3rd battery that is independent of all other batteries?
Will this battery run all day with the units on say 8 to 12 hours. I would charge the house battery when I come in.
If I can do this. What is the smallest battery I could use?

[charlie tuna]

What ever battery you have selected, or even both(?) - when your electronics shut down needs to be replaced. The electronics is shuting off due to low voltage, meaning the selected battery(s) has a problem. The problem could be that it is not being charged?? Or it doesn't hold a charge??
Why add an extra 40 pounds to your boat -- to haul around weak batteries. This is an early warning to tell you that you have a problem...

[Gulf Coast]

I have the same problem and don't hqve a weak battery.... thought bout running mine to the t/m

[Tidedancer]

Neither to I. New Optima batteries and kept on an on board charger when on the trailer. I looked at maybe one of these http://www.bluesea.com/products/7650/Ad ... _-_120ABut I think the spare battery is the way to go here.
On a 24 foot boat 40 extra pounds in not a big deal.

[DEMON]

Yes, your electronics will probably run all day on a single battery. Modern electronics with the exception of stereo/radios don't draw much juice.

[lonesouth]

why would you need the switch AND the ACR? Why not just the ACR?

[SS-342]

I would check all my connections as well.

[Badbagger]

I'm in the same boat sort of. I will have 4 batteries - ONE dedicated to starting and to the bilge - TWO for my trolling motor and you do not want electronics hooked to those batteries. Starting batteries are not designed to run electronics all day long nor a portion of the day. Given your application, the Starting battery is actually the LEAST critical one of the bunch. That said, you still want quality, and more-than-adequate capacity. The Owner's Manual for your (new) engine should give you the minimum requirements in terms of CCA. MCA and Reserve Capacity. You can of course go bigger; and at least within reason, that's probably a prudent thing to do. But don't get carried away. For example (and I'm ONLY pulling numbers out of thin air here; so don't take them literally), if the engine manufacturer specifies 700 CCA and 900 MCA, going to perhaps 900 CCA and 1,200 or so MCA would be a nice upgrade; but going to 2,000+ CCA or similar would be silly overkill.

I would suggest sticking to AGM-type batteries for this application, in part because it simplifies using an ACR/VSR to distribute charging current from the motor and/or your external charger to both the Starting and House banks. They are also easier to live with in the long term.

FWIW, a lot of folks also like the Sears DieHard Platinum AGM batteries (which are really relabeled Dekas). They're not bad, but size-for-size, their performance also tends to lag a bit behind the Lifeline & Rolls equivalents. They also don't offer as many different configurations & capacities as Lifeline or Rolls; so finding the "perfect match" for your application can be more difficult. But IF you happen to find a appropriate model (such as the Group 31M http://www.sears.com/diehard-platinu...p-02850131000P, for example) "on sale", they can represent good value.



http://www.lifelinebatteries.com/marineflyer.php?id=30
http://www.lifelinebatteries.com/marineflyer.php?id=4
http://rollsbattery.com/public/specsheets/30H125.pdf

Personally, I would not "skimp" on a good battery. Folks spend tens of thousands of dollars on boats and engines and look for "the cheapest batteries" only to end up having issues. My starting battery will be a Deka Starting Battery from Oreilly's Auto - Their Superstart Batteries and relabled Deka Battteries. I have to Deep Cycle Superstart Group 27's now for my Trolling Motor and will be adding the Sears Platnum Group 31 noted above. Just my two pennies and while $300 for a battery sounds expensive, it's powering those expensive GPS Units and bottom machines. Mine will power my Garmin GPSMAP 720S and the Lowrance Gen2 HDS 12" Touch unit that I'm about to order.

Hope this helps you. Folks in general have a LOT of issues due to low voltage problems with electronics and the vast majority of the time it can be tied directly to their battery or in cases and crummy wiring job.

[lonesouth]

I thought the Diehard platinum were rebadged Hawker Odyssey, not Deka...

[HewesMan]

Look for corrosion. Something is not getting a good connection especially if the battery is good. If it is a Merc Optimax then make sure you have enough CCA since they require a lot.

[MudDucker]

Another issue could be that the starter is going bad on your kicker and drawing way too many amps. Don't ask me how I know!