2x6v Deep cycle start bank and 2x12v regular house bank

[Compass790]

I think you don't need to worry if you are going to sell the boat.

It depends a bit on what your fridge draws, I assume you mean its a Peltier type, our old one used to draw 6amps on high & 2 on low.
You should be fine on low, sounds like you have enough battery capacity.
Its always better to have the same battery types in a bank.
We used to run a 780 CCA used start battery as our house battery ( It had no amp rating )
& that survived a couple of years no trouble. (Used 3 months full time ) but it had solar charging too. Was still fine when we sold it.
I'd guess that you'd get easy 2 years with whatever mix & match you do.

[George_SD]

UPDATE:
I've decided to install a third 12v (same as house bank one). They are not as good as 6v deep cycle, but they fit and now all three batteries are the same.

I've also picked up a 100w solar panel that came with a basic charge controller. The plan is connect it to the house bank. I think I will turn off the switch for the engine battery once on anchor.

Now trying to mount it on the stern rail, as that's the place that gets the least shade. So far the mounting hardware costs 1.5x of the solar panel.

The next question - is should i connect the charge controller to the house bank directly (negative post on one and positive post on the other) or somewhere else?

[Compass790]

The instructions should come with the controller.
We just tie the solar panels on the deck or the pulpit or lean them on the boom at anchor & shift them around to face the sun. We connected ours directly to the batteries but I'll leave it to the electrical gurus for other suggestions.
We have no trouble with the 20amp PWM controller. I paid $1 for it from China & has been going 5 years +.

[Wotname]

Originally Posted by George_SD

UPDATE:
.........

The next question - is should i connect the charge controller to the house bank directly (negative post on one and positive post on the other) or somewhere else?

Yes but do include a fuse in the +ve wire and locate this fuse at (or very near) the battery terminal.

[George_SD]

How do i select a fuse - should be rated to the solar pane, the controller? I have an inline waterproof fuse enclosure for automotive style fuses and can splice it in.


I heard that if the battery is disconnected from the controller, the solar panel will burn the controller. So I want to put a disconnect to for safety. I should probably add it to the Solar panel + lead, right?

[Wotname]

Originally Posted by George_SD

How do i select a fuse - should be rated to the solar pane, the controller? I have an inline waterproof fuse enclosure for automotive style fuses and can splice it in.


I heard that if the battery is disconnected from the controller, the solar panel will burn the controller. So I want to put a disconnect to for safety. I should probably add it to the Solar panel + lead, right?

Size the fuse for the wire size used between controller and battery; the fuse is there to protect the wire.

The panel can be 'turned off' by shading it e.g. placing a towel over it etc.

[George_SD]

So a quick update: Installed the solar setup and it is totally amazing. A single 100w panel recharges our housebank every day, powers the fridge/VHF/LED lights, recharges 2 iPhones and an iPad within a single day. Power wise, we can stay off-grid with the fridge running 24/7.


- 100w solar panel
- Renogy PWM controller
- fuses/breakers
- some aluminum stock metal
- stainless steel fittings


Total price ~$300

[Wotname]

Sounds like a great outcome - thanks for updating us