I think that old thread has some clues:
We have three batteries on our 35CB. There are two 8D's under the dinette seat. The shelf they sit on is marked Engine below one of them and House below the other. The third battery is a Group 27 or 31 for the generator and is located near the generator beneath the cockpit sole. None of these batteries are wired in parallel.Mariner wrote: ↑Fri Apr 13, 2012 7:07 pm It's important to understand that Albin grossly overbuilt their electrical handling systems, and, as a result, had to resort to some unconventional switching methods.
For example, in our boat, there were two main battery banks when it left the factory (a third was added later, but that is beside the point). Rather than the typical 1-ALL-2-OFF switch, feeding two batteries into a single load that serves both the engine and house, they used two such switches, side by side. This allows the Engine and House batteries, to service the Engine and House loads independently with no connection between the two. But it ALSO allows you to interconnect the two so that you can charge the house battery bank from the engine. The connectors for "2" on the switches just have a wire running between them (from one switch to the other). That way, by selecting "ALL" on both switches, you are combining both banks and both loads into one big system. But they didn't label ANY of this, nor did they provide a user's manual. So, unless you're the original owner who went through a detailed orientation with the dealer on how it works, or you've spent some serious time crawling around and tracing wires, you'd never understand any of it.
Since our boat has several different users, only some of which are interested in crawling around in the bilge, I started looking at alternatives to make it simpler to use. There are some charging relays that could be employed, but due to the over-building of the electrical system, the versions necessary to match the capacity of the rest of the system are extremely expensive (4 digits). Instead, I opted to do some custom labeling for the switches, and create a couple laminated instruction sheets that are attached to the switch panel, making it fairly simple to know how the switches are supposed to be set in any given situation. Now, remembering to make those switch changes as your situation changes....well that is another challenge.
Here are the battery switches:
They are just as Mariner describes: 1, 2, Both, Off. How did Albin intend these switches to be used? I understand Off, I think...except I don't know if the battery charger charges the batteries with the switch turned to Off. Some boats do; some don't.
The backs of the switches are interesting. I can really only see the top one (engine) well, but the next one down (generator) appears to be wired similarly:
Position 1 has 1 cable connected.
Position 2 has 2 cables and one small gauge wire connected.
Position Both has one cable connected.
I'm guessing that position 1 draws only from the associated battery.
Position 2 is beyond me. No clue.
Does Both parallel everything through the switch? What if you turn Engine to Both and House to 1? What happens then? What if you turn all three to Both? My probability skills are rusty, so I don't remember how many possible combinations there might be for these three switches and three positions. Even if it's only nine, that's mind-boggling.
How does 1, 2, Both make any sense when there are three batteries?? Seems like you'd need 1, 2, 3, *All* because "Both" isn't grammatically correct for anything other than a quantity of two.
You see my dilemma. Obviously we need to test a million combinations because even though the system may have been configured with some kind of logic from the factory, there's no guarantee that someone hasn't changed it. But it would be nice to understand what the original concept was.