Inverter Systems??

Beyond A Wake

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All of you who have inverter systems do you have the boat on constant charging when not in use? Since I am dry stacked that would not be possible without some hassle with cables in shed.
How big an inverter have you installed to run 3 ACS, Cabin Helm and freezer.
Can you also use an electric Grill and Microwave? And how about charging the starter battery(ies).

Of course the duty cycles can vary wildly and in my case when not fishing much it is mainly creature comfort and cruising that counts.

I used to have gas inboards and Gas generator on a sedan bridge and gen used gas tanks but could not drain the tank as the pick up was at 1/4 tank level I believe. So if tank goes to 1/4 gen is starved.

THe diesel in current case is not bothering me but I could like a larger tank!!

H
 

everwhom

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Here’s a thread on my 2000w inverter / charger install: https://www.greatgrady.com/threads/replacing-generator-with-inverter-on-330-express.33556/
My inverter battery bank is charged both by shore power but also by my outboards.

I love it — for my use it’s far better than a generator but I basically don’t use any high power devices, like Air Conditioning, for very long.

The quick math is you have to have an inverter that’s sized to the total amount of simultaneous wattage. My AC uses 1000 watts so in theory my 2000 watt inverter can handle the AC plus another 1000 watts like my electric grill. Running 3 or 4 Air conditioning units simultaneously would probably require a very large inverter system at least 5,000 watts which is pretty huge... As for battery capacity, you calculate the approximate DC amps required by taking the wattage and dividing by the voltage and then adding 10% (because the inverters are only about 90% efficient). So a 1,000 watt device powered by an inverter using a 12 volt DC source would consume about 90 amps of 12V DC, and to run it for an hour would consume 90 amp hours. So if you wanted to run it for 8 hours you'd need a minimum 270 amp hour battery bank, though you would generally need more to avoid fully depleting it. (Lithium batteries can be pretty much discharged to zero, but AGM should only be discharged to 20-50%)

If your motors can supply some of the current, like mine do, then your battery bank can be smaller.
 

seasick

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The system design would not be simple at all for that capacity. First of all, I am not sure what the OP wants to do.
Is the need for power only when at sea?

How would a system of that size be recharged? There is no info on the vessel but I would be concerned about the available capacity of the existing alternator equipment. If the hull is relatively small, a genset is probably the best approach but even that would probably be impractical to size for all those loads at the same time. Note that gen sets should be run at at least 50% of their rated capacity.
What is needed is a better description of the needs/wants.
 

everwhom

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The system design would not be simple at all for that capacity. First of all, I am not sure what the OP wants to do.
Is the need for power only when at sea?

How would a system of that size be recharged? There is no info on the vessel but I would be concerned about the available capacity of the existing alternator equipment. If the hull is relatively small, a genset is probably the best approach but even that would probably be impractical to size for all those loads at the same time. Note that gen sets should be run at at least 50% of their rated capacity.
What is needed is a better description of the needs/wants.

Completely agree!
 

Beyond A Wake

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This is more theoretical as looking if there is any experience in ditching the gen around. I was reading a multi year thread on the hull truth and a lot has been discussed and argued and systems have developed during the past 3 years.
I think in my case the current set up is good. I really only use power during the day and do not overnight on boat (as of yet anyway) so adding a huge battery bank would not be of real interest and most likely the charging systems would have to be redone Completely. I assume the Yamaha alternators are no good for LiPo charging and my current charger A Promoariner 50 would not suffice either.

Just a thought to toss around at times.
My boat is in my profile 2019 335 Freedom 3x300 Yamaha. Fisher Panda Diesel Gen 5kw with 12G? Tank, runtime likely less than 12 hours??

I would never run all loads at the same time. Likely one AC and Grill would be max simultaneous load. Only charging source would be from motors during running and in dry stack I could keep a charger on at night but not all the time anyway.

H
 

Automated14

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Battery capacity and inverters have come such a long way-that’s not the hard part. Recharging the batteries in a reasonable amount of time is the next hurdle. Solar won’t cut it and most twin outboards won’t either.

However, the new Yamaha 450 and Mercury v10’s specifically mention the upgraded charging systems. Arrowcat is already doing it with verado outboards but I don’t know what the practical run times are for AC and other high draws. I don’t think EV’s are the answer in general..yet- but batteries sure seem viable in replacing smaller marine gensets.
 

everwhom

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So my setup is two 100 amp hour AGM batteries for a usable capacity of 100 - 160 amp hours (depending on 50% or 80% discharge depth). My Yamaha 4.2L F250's provide about 30 - 40 amps each through the optional isolator charging wires that I have connected. So in theory, I can charge the bank up at about 60 amps / hour of running. So for my 120V AC needs which is mainly coffee maker, microwave, window defroster, and occasionally the air conditioner, I can easily keep the bank charged on outboards (I spend 3 weeks / year on a mooring without shore power which is also when I do my offshore overnights at NE canyons).

Pros: vastly cheaper than replacing my dead 20 year old original FP genset, no seacock to open or forget to close, completely silent, zero maintenance and winterization, no fueling, less weight

Cons: limited run time (though easily fixable by increasing battery capacity, esp with LiFePo), less wattage capacity (2,000 vs 4,200 from the FP)

I decided to go AGM for the battery bank because I could connect the outboard isolator wires directly to the batteries, but if I upgrade to lithium, I would need to add two Victron Orion 30 amp DC-DC converters which would make it safe for the outboards.
 
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Fin-Allie

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I thought about doing the same thing but in the end I installed a phaser generator after looking at everything you will still need to maintain the the electrical system