V21 Dual battery set up - suggestions ?

bgreene

Banned
Currently - 1 battery in the transom battery storage spot.

Considering- dual battery system, leaving the rear battery for starting the engine, plus the other battery inside the cuddy to power everything else.

Then a high quality switch that allows for an " all " position to use both if needed for engine starting.

Anyone have a set up they want to show pics or talk about ?


Thanks
 
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I have dual batteries in the console (CC boat). I don't have any pics right now but it's as follows.

Batteries mounted in console
4 way switch mounted in the cubby under the steering wheel
1 AWG running from engine to switch
1 AWG from batteries to switch
Power from the switch common to my fuse panel
Ground from the battery to fuse panel

The cranking battery is on the 1 position, deep cycle on 2, they both run an a parallel on the both position.

I run in the "both" position and switch to the deep cycle when at anchor.
 
I've put quite a bit of thought into this.... I believe I'm going to operate with one on/off switch between engine and starting battery and one off/1/2/both switch between everything else on the boat, the deep cycle, and starting battery with an acr between the batts..... the starting battery will ALWAYS be connected to the engine and trim unit except when stored... the multi switch will generally be switched to position 1 and run EVERYTHING except the engine and trim pump from the deep cycle but by switching it to both I can double up to start the engine from the deep cycle or by switching to position 2 I can run accys off of the start battery for whatever reason

The beauty of this setup is that I don't have to remember to switch anything and thus I can't accidentally run down both batteries while on the hook and the batts charge automatically. I'm also going to install an on board charger.
 
I've put quite a bit of thought into this.... I believe I'm going to operate with one on/off switch between engine and starting battery and one off/1/2/both switch between everything else on the boat, the deep cycle, and starting battery with an acr between the batts..... the starting battery will ALWAYS be connected to the engine and trim unit except when stored... the multi switch will generally be switched to position 1 and run EVERYTHING except the engine and trim pump from the deep cycle but by switching it to both I can double up to start the engine from the deep cycle or by switching to position 2 I can run accys off of the start battery for whatever reason

The beauty of this setup is that I don't have to remember to switch anything and thus I can't accidentally run down both batteries while on the hook and the batts charge automatically. I'm also going to install an on board charger.

I am a little confused by your set-up.

The "off/1/2/both switch" is installed in between the batteries and engine/accesories, right?

What is the point of the on/off switch?

Sounds like the same set-up as mine, but with an on/off switch between the starting battery.
 
no the engine and trim pump are connected to the start battery via the on/off switch

everything else is connected to either or both via the off/1/2/both switch and in normal operation are connected to only the deep cycle at all times

the big advantage of this system is that it is not touched except to disconnect batts for storage or in the case of a battery failure..... normally you have two separate systems and the start batt is only used for the engine

then the acr allows the engine to automatically charge the start batt first and then the deep cycle
 
ditch the deep cycle battery, run two good starting batteries. You'll be much better off ditching the deep cycle for a starting battery. the only reason to have a deep cycle battery on a boat is if you are running a trolling motor or running a battery bank with an invertor. With the acr and a a off-1-all-2 switch(stay away from the perkos, they don't hold up well), Wire the automatic bilge pump directly to one battery, everything else thru the switch. If you want to seprate the house systems from the engine, you can run three on-off switches. One will be hooked between battery 1 and the engine systems, the next switch is hooked between the house systems and battery 2, the last switch goes between the two battery's to allow an emergency position to connect both battery's together. You can run the dual battery switch in conjunction with a separate on off, but it can get confusing, what switch does what. Boston Whaler runs two combination switches on their dual engine boats, you have to read the instructions beside the switches to figure out what they are trying to do each time you turn the power on. Look at the Blue Seas diagrams and the battery management panels.
 
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the acr serves the same purpose as the traditional diode isolator but without the voltage drop. Also it has priority charging of the start batt and then thhe aux

I intend to use a deep cycle for my aux batt because I want to be able to operate the radio, sonar, lights, maybe a 12v fridge, and whatever else for extended periods of time without worrying about the batt..... I may at some point add troll'n'tabs but will have to add a third batt at that time.
Below is a crude sketch of my wiring plan. Sorry it looks so bad but it's hard to draw with a 2" touch pad.
batt switch.JPG

BTW FWIW on my big welly, I have 3 monster group 31 deep cycles for house batts and 1 lil group 24 starting batt for both merc 260's and the genny
 
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The add-a-battery kit is great. Simple solution that allows you to charge both batteries but have them isolated unless needed. My only thought about having the second battery in the cabin is you are going to have to run some long heavy gauge wiring up there and it won't be cheap. If you want that forward battery to be charging off the motor and especially if you want it to be used for emergency starting you are going to be spending a lot on battery cable.

-Svence
 
i for one have that blue sea system that spareparts is talking about and it works great. my electronics dont crash any more when i start the motor and i never had any trouble with my batteries. i even called their tech support for info and was well satisfied.:nice:
 
The Blue Seas switches are good but if you want better,try the BEP cluster switch. After all this is the 21st century ya know.
http://www.bepmarine.com/home-mainmenu-8/productcategory-205/clusters-manual

34qnxts.jpg
 
This question never gets old.......

Ive seen or heard just about every combo out there. At some point during this thread someone will realize their battery is hooked up wrong, someone will think their setup works better than anyone else's and the majority will rest assured knowing that "it just works, but I don't know how"...........Only advice I would offer is that you should be able to crank your engine from either battery.

I feel like everyones battery setup is as diverse as their sock drawer........Ive got my long-winters on the right and low-ankles on the left. Or do you think my gold-toe's need to be on the left and long-winters in the back???????

Ugh, life is too confusing............
 
This question never gets old.......
.Ive got my long-winters on the right and low-ankles on the left. Or do you think my gold-toe's need to be on the left and long-winters in the back???????


:clap: Thanks for the laugh, and man with organization like that you must have a big sock drawer. I go with the throw them all in one drawer and hope for the best approach.

-Svence
 
I have the Perko OFF-1-ALL-2 switch and am having battery problems right now. What is it about the Perko that goes bad? If I end up replacing batteries, it does make sense to go with two starting instead of one of each. I only run stero, two radios, and two electronics.

BTW, what kind of batteries should I get if I replace them? Barracuda?, Exide?, some other brand?, whatever they have at autozone? What can be done to preserve my batteries? I do have a Guest onboard dual charger, but for the most part I only plug it in for 24 hours before each trip.
 
the perkos are ok, but they give problems after they've had some use, especially if you've tried to start an engine with a weak battery, The best tool you can buy for checking your battery system is a load tester, harbor freight has them pretty cheap, I use my load tester weekly to diagnose all kids of electrical issues
 
I do have a Guest onboard dual charger, but for the most part I only plug it in for 24 hours before each trip.


Thacker, your question prior to this statement about how to prolong battery life...IMO and my experience, yer missing the greatest thing about having the onboard Guest charger...the best way to prolong batteries for the long haul is to keep them HOT...and that's what leaving that charger plugged in all the time does...I had a Guest 2620 20 amp (10 amps per leg) on two group 31 AC Delco Voyager deep cycles used for elec trolling motor...those batteries lasted 9 YEARS and only failed after they were not left on that charger by the next owner...Batteries like two things...to stay hot and not be completely drained...mine stayed plugged in 24/7
 
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