Pure sine wave inverter upgrade?

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Dwk

Senior Member
Joined
Jan 21, 2014
Messages
410
Location
USA
Vessel Name
Patty Ann
Vessel Make
Mainship 34 MK1 1980
Currently our 1980 MK1 has a 1000 watt modified inverter. With so many choices available I looking for experiences,comments,recommendations of 2000 watt pure sine wave inverters that group members have in service or experience with. Part of the upgrade is the house battery which now consists of only one 8 D battery,obviously not enough power. What would be the most practical house bank to supply this inverter. Alternator is 125 amp,generator is 3kw,charger is 10 amp. All advise appreciated to accomplish this upgrade. Thanks David

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Are you looking for just an inverter or inverter/charger. With a 3kw gen I would be looking at the Victron with overload assist and maybe 4 T105 GC batts. I like an integrated system.
 
Are you looking for just an inverter or inverter/charger. With a 3kw gen I would be looking at the Victron with overload assist and maybe 4 T105 GC batts. I like an integrated system.
I'm interested inverter without charger.I'll add separate larger charger. thanks for the response
 
Look at Mastervolts line, they make some nice stuff.
 
You might consider and inverter/charger along with a stand-alone charger. I think an inverter/charger is typically not much more $$ than just an inverter. And the extra charge capacity can come in real handy for getting batteries charged quickly when on your generator.
 
Why would you want an inverter/charger and a charger. The batt charger built into the inverter is better and way more powerfull than any stand alone charger that you would normally buy. The inverter/charger combo is cheaper and better.
 
Why would you want an inverter/charger and a charger. The batt charger built into the inverter is better and way more powerfull than any stand alone charger that you would normally buy. The inverter/charger combo is cheaper and better.

:thumb::thumb::thumb:
 
For the reason I said - faster recharge from your generator. There are lots of 100A stand-alone chargers available which is as good or better than a typical inverter/charger. Running both means faster recharge and less generator run time. What's not to like, other than the extra cost of the equipment, which of course is a perfectly good reason not to do it.

But the OP said he was considering separate inverter and charger. I was just trying to point out that for a slight increment in cost he could have an inverter/charger along with his charger and get faster charge times.
 
We have an inverter/charger for the house bank and a separate Newmar charger for genset and engine starts. In a pinch the Newmar through the // switch can charge the house bank too.

I must admit I am a Gemini so have twin engines; redundancy is a personal credo. And two flashlights, anchors, rode, coffee pots, heads, fuel filters, chart plotters, helm stations, sets of sockets, depth sounders, VHFs, can opener, sets of sheets ad infinitum. :thumb::thumb:
 
I would say that you will need about 4 to 500 amp hrs of deep cycle batteries. Whether you chose a stand alone inverter or a combination with charger, your charging system needs some serious upgrading. We have an 1800 watt pure sine wave inverter. We run the TVs, frig, and ice maker. from the inverter. Works well for us.
 
2 inverter/chargers would still be cheaper than 1 inverter and 1 100 amp charger. And, you would have redundant inverting and charging ability. A 2000 watt inverter can charge at 100 amps. Plus, the controll panels can be mounted in easy view. they are easily configurable for your needs. 2 inverters can be tied together to provide 240 volt a.c. if needed. I can see the desire to have stand alone chargers for start and gen batts. Although it can be done with any number of other options.
 
However, a warning for using an integrated charger/inverter with a defect is both the charger and the inverter out of use. I prefer splitting up both of them.

CeesH
 
So you want a pure sine wave inverter. What about the current modified sine inverter doesn't meet your needs? The need for more power doesn't dictate the need for a pure sine wave. Pocket depth may be a ligitamate reason. But the difference between a modified sine wave and a pure sine wave is something I see as generaly misunderstood. 120 volt AC has a peak to peak voltage of about 170 volts. That sounds like a lot but power being equal, in reality is not so much. Power or watts is the area under the curve of a sine wave or a modified sine wave. Power being equal, the differrnce. between the two can only be felt by loads involving a transformer. Microwaves, battery chargers will operate slower on a modified sine wave, but the actual differnce is probably pretty small. The difference between an inverter charger vs. an inverter and separate charger is a personal choice. However, on a practical note the cost of an inverter charger vs seperate units is much cheaper. A 2000W inverter/charger will provide something close to 100A of charge power. The cost to replicate that power with independant units will probably nearly double the cost of the inverter/charger. Being a redundancy fan my self, why not use a inverter/caharger and have back up charger capability. It may be half the inverter/charger output but is available if you need it. If you buy a quality inverter/charger, the probability of needing it is small. Just the opinion of a cheap curmudgeon, but I am also a capitalist, who never wants to get in way of a guy who wants to spend money.
 
If you want to run air cond ,big water maker, or scuba refill underway (all have large heavily loaded AC motors),,,

OR if you want to parallel and boost rotten dockside current (to start an appliance or boost a modest sized noisemaker , a Sine Wave inverter is needed.

Otherwise a large sine wave inverter is a waste of currency.

Inverter chargers are nice , till something goes , then you have neither.

Dockside with easy UPS , no big deal , underway cruising , a big PIA!

Your choice,
 
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FF ,Not certain what you mean by this.. " Dockside with easy UPS, no big deal, underway cruising ,a big PIA! " My usesage of inverter would be mainly fridge,charging electronics,microwave,java maker using at different times of course ...Is a 2000 w sine wave overkill? Need advice,thanks
 
My strong advice is to put this jumble of answers aside for now, and get a copy of Nigel Calder's "Boat Owner's Mechanical and Electrical Manual" (an invaluable tome on a iwde range of boat systems) , read the first three chapters, then come back here with equipment-specific questions if you still have any. Reading this well written and easy to understand book,you will have both education about electrical issues, and specific direction on specifying setting up an inverter system, batteries, chargers, and alternators.
 
We have been using a Xantrex Prowatt 2000 for the last four years. Some folks have negative opinions on Xantrex but ours has worked well for four years. Its about $400. The only challenge with it is that you have to plug it in and be very careful that you don't tie dock power AC to the inverter. I know because when I first bought the boat I blew up a 1500 watt inverter due to plugging it in with shore power on the boat.
Doing a little research it looks like the inverter charger market is really increasing due to the rise of solar. A good name 2000 watt inverter charger is $1200 - $1800. I found one for $575 that has a built in 40 amp charger. The good inverter chargers have built in transfer devices that would eliminated my previous blow up issue.
When my inverter goes I will purchase an inverter/charger and keep my 40 amp charger to prevent the single point vulnerability. Good luck
 
My usesage of inverter would be mainly fridge,charging electronics,microwave,java maker using at different times of course ...Is a 2000 w sine wave overkill? Need advice,thanks

2000 watt isn't over kill IMHO.
Microwave 600-1500 watt
Coffee maker 800 watt
Toaster 800-1500 watt
As you can see if your appliances are on the high end you would overload a 2000 watt running two appliances at the same time. You just need to manage it.
 
Last year at this time, my xantrex 2500 modified wave quit, so after some research, I replaced it with a Magum 2000 pure wave with charger. In my
Opinion this is not overkill. As mentioned above, using a refer, microwave ,
Coffee pot, you still have to watch it...... Just adding my 2 cents.

Frank
 
We use the Xantrex SW series and have had ours in service for several years running 24X7X365

In this day and age no need to go modified sine wave.
 
Big fan of the combined units. When charging batteries with a generator it make sense to use a large charger and cut your run time.

Modified sine wave is not a good idea for a cruising boat. You may buy a TV or computer that doesn't accept MSW. I destroyed more than one charger for my battery operated drill when I plugged it into a MSW inverter.
 
FF ,Not certain what you mean by this.. " Dockside with easy UPS, no big deal, underway cruising ,a big PIA! " My usesage of inverter would be mainly fridge,charging electronics,microwave,java maker using at different times of course ...Is a 2000 w sine wave overkill? Need advice,thanks

I don't think FF has been back, but I think UPS is United Parcel Service. He is right in what he is saying. When the inverter/charger goes out while you are cruising you are screwed. You may have to run the generator full time to run the few electrics. The only way to charge your batteries is by running the main engine. Losing one is not good. Losing both can be disastrous for your cruise.
 
I still think 2 inverter/charges would be better and cheaper than 1 inverter and a 100 amp charger. If 2000 watts is enough get a pair of 1000 watt (or better, a pair of 1500s) inverter/chargers and tie them together. Now we are redundant x2.
 
I still think 2 inverter/charges would be better and cheaper than 1 inverter and a 100 amp charger. If 2000 watts is enough get a pair of 1000 watt (or better, a pair of 1500s) inverter/chargers and tie them together. Now we are redundant x2.

Yes, that sounds good too. Redundancy is good, and so is high charge capacity. The more you can make that happen the better.
 
Two inverters will cost more to install, especially if the inverters are located any distance from the batteries. When you get into the 0 or 1 awg sizes, or larger, cable gets very expensive per foot. The existing cables from your charger to the batteries are likely to be substantially undersized for an inverter.

If you plan on hard wiring the inverter(s) into your AC distribution system, you have to insure that two sources of AC power cannot be connected at the same time. I believe that some of the newer inverters (Victron and Mastervolt) can communicate and allow for more than one inverter to be used at the same time.

I also believe that an inverter/charger setup increases the chance of failure. Not only will that cause a loss of the inverter/charger, but if the system is wired through an AC transfer switch, you will also lose shore power and generator power to the inverter circuits.
 
Opinion: suggested arrangement. If the boat has a generator a combined inverter charger with a 100 amp charging capacity. As a backup charger a 30 amp charger such as the Promatics. Thus if the combined unit goes down you can get AC from the generator. The generators alternator and the 30 amp charger will give you approximately 60 plus amps of charging.


If you do not have a generator things are different, you can't use a charger away from the dock so a 20 or 30 amp charger will be sufficient. In that case a 1000 amp inverter would work.

Many cruising trawlers have two inverter/ charger units in case of breakdown. I bought my second unit when anchored (mooring ball) off New York City. My inverter charger broke and was going to take a week to have fixed. The cost of a marina in NYC for a week would have neared the cost of a second inverter charger. Now we are set up to run both chargers at the same time. Cuts generator run time almost in half. With the price of diesel here in the Caribbean the reduction in run time has paid for the second inverter/charger.
 
Super overkill,

Nothing named is high AC motor load , a non sine wave would do just fine.

With your limited loads a 1200- 1800W unit at under $200 should be fine.

Use the toaster or and coffee machine at different times from the microwave.

And make sure it can power the blender for Margaritas at sundown!!
 
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My Splendide washer/dryer will not run on modified sine wave. BlueYonder is correct that installation will cost more, 2/0 copper is expensive. Try to put the inverter(s) as close to the house bank as possible. If the inverter has a pass thru for a.c. you should have a "go around" switch. I use a 30 amp shore/gen rotary switch. This allows you to bypass the inverter entirely if it takes a crap. As for a charger backup, I carry a 50 amp portable automotive type charger. I dont use it much but it has gotten lots of other captains out of a jam when there batts are dead and they have a charter. Very cheap backup.
 
"As for a charger backup, I carry a 50 amp portable automotive type charger."

Be sure to check it ,as all auto chargers must be checked, that the neutral & ground are not connected electrically .

Could get exciting!!
 
"As for a charger backup, I carry a 50 amp portable automotive type charger."

Be sure to check it ,as all auto chargers must be checked, that the neutral & ground are not connected electrically .

Could get exciting!!

Wouldn't this be solved by plugging the charger into an onboard electric outlet? Or are you talking about the internal wiring in the charger?
 
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