So, the inverter/charger on my boat finally died (20yo) and it’s time for a replacement. I was strongly looking to leverage the Victron ecosystem, as future plans include a solar install and upgrade of LA batteries to LFP. My immediate, short term need is to find the right Multiplus/Quattro to fit my current infrastructure and needs.
Here is what I have :
50A 240V AC shore power connection (run thru isolating transformer)
240V generator
240V A/C system (which I was not currently planning on running off of inverter)
12V LA 2 bank system (starter battery and 3 8D house bank)
Various 12V DC and 120V AC power requirements
Dead charger/inverter was 120V AC/12V DC
Planned requirements :
Primary anchoring/cruising, with expected primary power source being generator/solar/shore, in that order.
No initial plan/requirement to run 240V air conditioning off batteries thru invertor. (But future option MIGHT be nice)
Have not had much luck finding the “right” web page with a side by side comparison across Victron, so not sure between Multiplus/Multiplus II/Multiplus II 2x120V/Quattro/Quattro II 2x120V. Again, with the current system DOA, I’m hoping for a quick answer to the right product so that I can get back out on the water, but don’t want to buy something that I’ll regret in 12-24 months.
Major difference between the Quatro series and the Multiplus series is that the Quatros have 2 AC inputs - this might be useful for simplifying wiring for Gen input and shore power. Do make sure to use an isolating transformer for the latter.
If you have more 240V loads than 120, it also might be simpler to use an auto transformer on the inverter output to provide the 120v. You don’t mention your gen capacity or the max load requirement. If working at or above 3kW of inverter power, I would look at raising the house bank voltage to 24V, though this does add a number of complications. above 5kW, this should go to 48V. This keeps the max conductor sizes down and saves a bundle on copper costs (and inverter costs).
If designing a system for a later upgrade, do remember that inverters can be paralleled for higher powers, but only if the same model.
Mike - Appreciate the feedback. While yes, I do technically have the 2 AC inputs (shore and gen), I’d never have the need for both at the same time, and the boat is already set up with a pretty safe and straightforward mechanism for switching between (which we’ve got used to the last couple of seasons with the boat). And as I believe I mentioned, our only 240v load is the air conditioning, which we use on shore power when wind direction and hatch directions don’t always coincide, or for short stints on anchor with the generator to bring temps down before bed and while topping off batteries. And I hear what you’re saying about upping the voltage on the house bank, if the loads demanded it. But we’ve been managing so far with what we have and the wiring is already set up for it. If I was doing a complete rewire, I might explore options further - but leaning more towards a plug and play solution. I’m still a little on the fence regarding Multiplus II vs Multiplus II 2x 120V, but hope to get that nailed down by tomorrow.