Help me learn: Batteries for Dummies & Selector Switch Box Connections

[282Captain]

New to this forum, I have all kinds of questions I have had for years but never had the audience to discuss with.


I think a new battery replacement last year by marina accidentally changed how my batteries are connected to my switch box. I have 4 batteries...two on port. Two on starboard. Switch box has two dials, each with Battery 1 or Battery 2 or Both. I understand I should run on Battery 1 and Battery 2 under normal conditions. Guilty of running both dials on “both” as it seams to always meet my needs without the guess work.

I need to run some tests this weekend and take notes on exactly what battery selection effects what. But from memory, I know just one of my selector switches effects interior power. Can’t remember if on that switch if it’s battery 1 or 2 or Both of them work. I think this switch selector powers interior on any of the three settings...and maybe an engine for start. Here is the complication: My other selector switch does not effect interior power or seem to have any noticeable impact before motor start. Is this correct? Twin motors/4 batteries/two selector switches? How do I start trying to figure out if my battery switches are connected correctly? I always feel start up is best on both, so that’s how I always do it and leave it there.

I can’t find any literature about correct battery connections.

Finally, the old question how to run stereo w/o running the engine meter. I have never really mastered this or understood why any manufacturer does this. Thus, I have never had tunes when motors are off. Got a pretty good set up using portable bluetooth speakers and cell phone with XM radio. However, as I have a few plans this Labor Day weekend to review boat systems and do system checks, I thought I would throw out “Batteries for Dummies Questions”.

Happy Labor Day weekend!

[cmattj]

With twins it changes slighty in rigging.

As each engine runs on its own, the riggers at Cobalt decided which #1 or #2 system would control radio and accessory items.
My switch panel is the same as yours, and as "All" can combine (its not recommend for the fact that alternators and battery resistance can be shared). "All" is the ability when one bank is weak and lacks voltage to fire the engines.

I separate the sources for each engine. Right switch # 1 battery to port. Left switch #2 battery to Starboard then occasionally Ill change it up just because.

Radio, and amps will run with left key switch (port engine) in the accessory position. ( Turned left like a car ).

You could run the battery switched #1 to dead, and still have switch #2 or all to start both engines then. leaving in all will then help regain the voltage as you don't want to move the switch during charging and running. Engine hours on the ECM only record hours when running although your dash display hours can change with key to right.
I actually played with just one engine at at time and measured my charging output from the alternators to the charge lugs next to the switches. I then started the other engine on #2 and did the same to insure both charging systems were working good and independently.

With the port engine on # 1, (Right switch panel).... I figure out Radio etc, and how the riggers decided to allow fridge operation on that one bank as well. Where as the windlass runs on # 2 bank?? . (windlass operations is always advised with the engine running by the way ).
Long story short you have two boats back there... But they can charge a common 12v source if needed. It also depended on the rigger that day as ive seen some difference in other twin set ups as-well.

[282Captain]

Great explanation. I’ll be curious how mine is set up. Thanks for the detailed follow up.

[Driller]

Who's on #1? What's on #2. I don't know is #2 on second selector. This is most confusing explanation I have seen. You must have to have been there.

[cmattj]

Who's on #1? What's on #2. I don't know is #2 on second selector. This is most confusing explanation I have seen. You must have to have been there.

Let me slow her down for my Single switch brother. This panel is ridiculously located tucked away under the Port pass u seat.
Soooooo....
The one that's harder to reach ( Right ) is for the port side bank, and engine primary. The easy one ( left ) is for the Starboard engine bank and engine primary. Her is an illustrations as you can see how they can be shared ... separated or swapped side to side in battery selection just by choosing #2 instead of #1 and visa versa. You could run starters and engines both on #1 Or #2 and leave a bank of batters asleep but some accessories may not work.

Or just run-em on all for Driller and call it good.

Here is an example of a Twin set up. Not from a Cobalt.

[Big Block Power]

Radio, and amps will run with left key switch (port engine) in the accessory position. ( Turned left like a car ).

I'm just wondering if there a different left then I'm used to? Like Nascar they turn left right?

[cmattj]

Radio, and amps will run with left key switch (port engine) in the accessory position. ( Turned left like a car ).

I'm just wondering if there a different left then I'm used to? Like Nascar they turn left right?

Sheesh.. Your not right.. (see what I did there)

[Big Block Power]

Radio, and amps will run with left key switch (port engine) in the accessory position. ( Turned left like a car ).

I'm just wondering if there a different left then I'm used to? Like Nascar they turn left right?

Sheesh.. Your not right.. (see what I did there)

I left you in the wind along time ago. (c what I did there)

[Driller]

A wiring diagram I understand. Thanks for having patience with me Cmaatj.

[cmattj]

A wiring diagram I understand. Thanks for having patience with me Cmaatj.

Always my buddy! You know I tend to ramble.. Which brings me to ... nevermind

[282Captain]

Here is the bat box for Cobalt 282. I was going to type what I learned but can’t remember. I’m already at the lake bar.