V21 Dual battery set up - suggestions ?

[bgreene]

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

[Curapa]

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.

[spareparts]

check in to a battery combiner, or acr http://bluesea.com/category/78/79/pr...e/overview/329

btw there is a ton of good information on the blue seas site

[smokeonthewater]

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.

[Curapa]

Originally Posted by smokeonthewater

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.

[smokeonthewater]

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

[reelapeelin]

Originally Posted by spareparts

check in to a battery combiner, or acr http://bluesea.com/category/78/79/pr...e/overview/329

btw there is a ton of good information on the blue seas site

Is the combiner AKA an "isolator"??...

[reelapeelin]

Originally Posted by spareparts

check in to a battery combiner, or acr http://bluesea.com/category/78/79/pr...e/overview/329

btw there is a ton of good information on the blue seas site

Is the combiner AKA an "isolator"??...

[smokeonthewater]

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

[csvencer]

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