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Which inverter/charger & solar controller for 3kW, 110V AC and 12V DC?

jdege

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Dec 16, 2020
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I'm working on turning an old sailboat into a live-aboard.

What I have now is a 27hp diesel, with a 22aV lead acid starter battery and a second 12V, 100Ah lead acid house battery. The only charging source is the alternator (and the trickle charger in my basement, when I pull the batteries over the winter.)

Eventually I want a lithium house bank, providing 12V DC and 120V AC, with enough solar to keep it charged. ("Enough" is yet to be determined.)

What I'm looking to do now is to install a shore power connector and an inverter/charger. I'd like something that could pass thru AC from shore power, when connected, and charge the existing batteries, but would be capable of providing AC from the new lithium bank, when I install it.

But where do I find such a thing? I've heard people recommend Victron, but Victron has dozens of models, and I have no idea which would suit my needs.

Truthfully, I'd really love it if someone made an inverter/charger/solar controller. Looking at their website, Victron seems to, but only in 48V or 240V.

Or am I just reading things wrong?
 
I'd really love it if someone made an inverter/charger/solar controller.
Many companies make these. They are typically referred to as an "all-in-one". Victron does not have one for the US market that I've seen.

But a Victron MultiPlus (inverter/charger) and a Victron SmartSolar charge controller is a great combo for getting exactly what you need (once you figure out your exact needs).

Determine what system voltage you want/need (12V, 24V, or 48V). Determine how much battery you need, how much inverter wattage you need, and how much solar you need. Then you can choose the proper inverter/charger and solar charge controller.
 
I'm working on turning an old sailboat into a live-aboard.

What I have now is a 27hp diesel, with a 22aV lead acid starter battery and a second 12V, 100Ah lead acid house battery. The only charging source is the alternator (and the trickle charger in my basement, when I pull the batteries over the winter.)

Eventually I want a lithium house bank, providing 12V DC and 120V AC, with enough solar to keep it charged. ("Enough" is yet to be determined.)

What I'm looking to do now is to install a shore power connector and an inverter/charger. I'd like something that could pass thru AC from shore power, when connected, and charge the existing batteries, but would be capable of providing AC from the new lithium bank, when I install it.
Truthfully, I'd really love it if someone made an inverter/charger/solar controller. Looking at their website, Victron seems to, but only in 48V or 240V.

Or am I just reading things wrong?
For things that are suitable to the marine environment, it's hard to go wrong with Victron.

The biggest issue with what you're proposing is that no matter what the source is, a 3000W inverter is going to be realistically oversized for a 100Ahr battery, especially a Lead Acid battery where you realistically can only use 50AHr of that at most. That said, the Victron 12/3000-120 is a very nice piece of kit.

The other thing to consider is that you're probably better off with multiple smaller solar charge controllers working together than one large one integrated into your inverter/charger. This lets you optimally tailor your panels to where they fit on your boat (eg big 300A panels on an arch over the stern and smaller 120W panels on your dodger). Your best way to deal with this is two separate controllers.
 
For things that are suitable to the marine environment, it's hard to go wrong with Victron.

The biggest issue with what you're proposing is that no matter what the source is, a 3000W inverter is going to be realistically oversized for a 100Ahr battery, especially a Lead Acid battery where you realistically can only use 50AHr of that at most. That said, the Victron 12/3000-120 is a very nice piece of kit.
The is the first of several steps. I intend to replace that 100Ah house battery with a larger bank of LiFePO4, and eventually to replace the diesel with electric. I understand that a single 100Ah lead acid won't push 3kW for very long. But don't expect to have only that single 100Ah for very long.

I'd not considered the advantages of separate solar controllers. Separate controllers could minimize loss from shading, as well.
 
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