Some thoughts and right up front, I am a BIG fan of this inverter.
Pascal is absolutely right about the limitation re the single 30A 120vac input to the Outback. That 30 amps will be divided, if necessary, to provide charging for the batts and power to whatever device the inverter is connected to. Whether that has any actual impact will depend on how you set it up the circuits.
With ac power to the boat (genny or shore) the inverter's maximum charging power will be reduced as necessary if other AC loads on the pass-through circuit exceed 11 Amps. The max charging power of the inverter is 19A at 120vac - about 60 amps to the batts. So whether you have no ac power being pulled from the inverter circuit to run something or you have 11 amps being pulled by devices connected to the inverter, the charging max output is the same to the batts (and more than the oem Lamarche charger could deliver).
OK, so what does that mean for practical operation? Well, it depends on what is connected to the inverter. In our case, the inverter or its pass-thru circuit powers: the fridge wall socket, the microwave wall socket, the stereo/tv sockets, one master stateroom wall socket, the shore power cable extender, and the davit. I have never observed the charging rate to be reduced except if a hair dryer or the davit was running in combination with other devices. The usual and more constant duty items have no impact at all. The typical load at the tv and stereo sockets is seldom more than 2A when operating. All the voltages/division of power are visible using the Outback "mate" which is optional but after NOT having it for a year, based on Sky's recommendation, I purchased it and now also recommend that you purchase it with the outback.
Obviously, if you set up the inverter to run more AC stuff, then at some point you could reduce the charging to the point where it makes a difference. But for us, there is no downside at all. The LaMarche used to take 5-6 hours to recharge the batts from around 12-15 hours on the hook; the Outback will do it in 2. It is a far more efficient charger and a really efficient inverter.
The other limitation Pascal noted is the fact that the inverter has ONE charging output. That means that it can only charge one bank of batteries. Obviously, the oem Hatt setup is for two separate banks. So in order to use ONLY an outback and nothing else you either have to come up with a 32V battery combiner (which I could never find), or physically combine the two Hatt banks, which is what I did.
I used a regular batt switch and tied the two banks together through it so if I wanted, I could decombine them just by turning the switch off. The old Lamarche charger is still in place and I could decombine the batt banks, turn on the lamarche, and have totally separate charging. I have never done that. In fact, if the old Lamarche didn't weigh 145 lbs, I would have removed it but it's too heavy for me to do alone. Maybe next month I'll recruit Jim R to help me do that!
Now, IMHO, this is important re combining the banks: Hatt set them up so if the house bank was drained, the start bank could still start the engs and generator. Obviously, it is theoretically possible, with my banks combined, to drain the batts sufficiently where the engs can't start. That has never happened but it IS possible. In our case, our 16kw NL generator uses a 12v starter so we have a 2 battery 12v bank for that purpose. SO, even if we did drain the mains, the genny can still be started and charge the main banks. If we did serious offshore work at anchor fishing or whatever, I would NOT combine the banks. Sure, the genny can still start/charge the mains but offshore I would be concerned that a situation might come up where I need the engs starting RIGHT NOW, not in 30-40 minutes.
Where we cruise, in the Chesapeake bay, I don't see it as an issue at all. If everything failed - both engines blow up, whatever, you just toss the FX55 Fortress over the side with 100 feet of chain and you'll be wherever that anchor sets until somebody helps you or global warming raises the water level enough lift the boat straight above it and (maybe) pull the anchor loose.
If our genny was oem and started from the 32v banks, I would also not combine the batt banks. So that might also be a consideration for folks. But I add again that with the banks combined and the boat on the hook just running on the inverter for 15-16 hours, the engines started instantly. Frankly, with the combined banks the starters spin more agressively than they ever did with separate banks.
Hope this is helpful...
