Battery switch positions??
 

Here is my set up.

2 batteries
2 seperate switches 1 2 & ALL
On board charger

When running: Battery 1 set @ 1
Battery 2 set @ 2
Both to all to start

Here is my question:

When hooked to shore power where do I set my switches and do I leave the battery charger on??


thanks

WHEN I HOOK UP TO SHORE POWER THE FIRST AND NUMBER ONE THING I DO IS TURN THE BATTERY CHARGER ON.

You have many things that still run on DC.

I leave both of my switches to "all" or "Both" pretty much all the time. Have never had a problem.

What I think you should do is....
First you need a battery isolator (automatic charging relay). This will allow you charge both batteries with the switches in the OFF position. The isolator will charge the lowest batt first then the other batt.
Are both batteries labeled as "CRANKING" batteries? If one is a deep cycle only, using it to crank the engine can damage it. On mine I have two batteries, one cranking and one deep cycle. I use the cranking for starting and the other is for everything else.
Also, when you connect both batteries together if one has a lower charge than the other the higher charge will drain into the lower till both are equal. Then you have two partially charged batteries. If one batt has a bad cell it will drain both till dead.

If your charger is an automatic type it should go to a lower amperage to keep the batts charged. If not, then you need to keep an eye on them to prevent overcharging and boiling the electrolyte out. Either way they need to be watched till you know exactly what they are doing.

On my boat I have an ON/Off switch for each battery and then I believe a switch for BOTH. I thought you should only run BOTH if one of the two batteries was dead or low and you needed the extra "Boost". Then switch off of BOTH. I may be wrong but I don't think you want to run all the time with BOTH, but I could be wrong.

Its all gonna depend on the charger and how its wired in the boat!
First thing you should do is inspect the battery charger and see how many banks it has....if its a single bank charger then leave the switches on "all" and it will charge both battery's at the same time.....If it has two or more banks then you will need to check how your charger is wired to the batteries....

if its going straight to the terminals of the batteries then i would leave the switches off unless you have something that needs DC power

Most of the battery switches indicate that you shouldn't switch positions while the motor is running.

Secondly, if you run the batteries on "all" all the time and you have an electrical malfunction it can kill both motors. If you run them separately the risk of killing both motors is eleminated.

But,,,, I've done it both ways an it's never really caused a problem either way...

Guys he's asking about how to set the battery switches when on the shore power charging the batteries...

He said when he's running he has them on 1-1 2-2 all-start

If I remember there was an issue about efi engines and battery switchs. If ran in both there was a breakdown in the computer or ignition system. Not totaly sure what the issue was but was posted here. I think Insptch was in the thread.

I realized that but he also said that when running: Battery 1 set @ 1. Battery 2 set @ 2. Both to all to start.

Most battery switches are not meant to be switched while it's running or under a load.

The battery charger should be set up with two banks, one for each battery. It also depends how the battery charget is hooked up. Is it hard wired to the battery or is it wired to the switch? If the batteries are switched to "All" it kinda defeats the purpose of having separate banks on the charger. If the charger is a single bank charger then the battery swtiches should be set to all.

Rule of thumb though... If you have two batteries always get a two or three bank charger. If one bank craps out you have a spare and you also have room for adding a 3rd house battery to run all your house electronics and save the other two batteries for starting only. Isolators also help because they isolate the battery that's weak and divert the aperage to that battery.

Why would you need to switch to 'Both' for starting? Seems like a hassle, unnecessary step.

I was under the impression the switches could be switched while running, but not thru the 'off' position. 1-both-2, not 1-off-2.

Mine is setup as you stated. twin batteries, 2 bank charger hardwired directly to each battery. Position of the 2 switches doesn't effect the charging this way.