V21 Dual battery set up - suggestions ?

[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

[spareparts]

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.