Simple Battery Management

[Benny]

For years we used analog voltmeters to monitor battery charge, I wonder how we survived?

 

[Stu Jackson]

I'm of the opinion that monitors are not that accurate. Especially when you do a lot of cruising and don't get the batteries fully charged for long periods of time. They never auto reset due to a full charge being on the batteries and so get out of sync with reality. I'd be interested in finding out how folks with monitors use their boats.

I do think it is a great resource to size components and learn how things interact. FWIW

Bill,

Donalex and I and a few others discussed this awhile back.

The issues,rather, is in finding out how folks with boats use their monitors. I agree about the resource.

It's the calculation of the "full" that's interesting, especially when between the 50 to 80%. A manual CEF is preferred.

I'll see if I can find the link to that thread, if not I copied it for own files and can post it.

Just more vividly arcane details for the algorithm-challenged.

 

[Stu Jackson]

For years we used analog voltmeters to monitor battery charge, I wonder how we survived?

And you're still driving a Model T, why???

 

[Bill Roosa]

Digital volt meters work too

The original post was along the lines of how do I tell how much my batteries are charged if all I have is a volt meter.
I have an analog meter like Benny but am pretty sure that a digital one would work just as good, probably make reading that 0.1 volt difference a little easier on my old eyes but it would not go with the decor in the boat.
I'll admit that specific gravity is the de-facto answer but testing 24 cells to find the state of charge is a pain.
soap box please
If you understand how much energy you are using and producing, the latter being the harder part because it is not a linear relationship, you can develop a sense of how far you can push your batteries and just use the volt meter as a confirmation.