Good Budget inverter/charger

The OE battery charger on our Mainship died this week, and the batteries are due for replacement.

Current setup, which was the way the boat was equipped new is 2 8D which handle both house and start loads, powered by a 40 amp ac charger. No inverter at all. I don't love this setup, I've honestly been waiting for the batts to go to make a change to a 6V house bank and a dedicated start bank (likely 1 4D to start both motors).

But I was not expecting to lose the charger at the same time. Now I'm considering installing an inverter/charger at the same time, but I'm on a budget. I'd like to find something for close to $1,000. If I just replace the charger I'll go with Mastervolt power charge which is about $400.

Load on the inverter would be occasional laptop and phone charging, sometimes a small coffee maker, and a small 4.5cf home style chest freezer.

Can it be done on my budget of $1,000 not counting the batts?

Yes, it can be easily done. While I am not a big fan of Xantrex products their new Freedom HF 1,800 watt inverter with a 40 amp charger looks like a real deal. It has a removable front panel that can be remote mounted so you don't have to buy a separate one. Defender has them for about $500. Go to Xantrex Freedom HF 1800 Power Inverter / Charger

Your house bank of 600+ AH will require 50A or more to adequately charge for short periods on the generator. 100A would be better, of course, but not always practical depending on generator capacity. (I use a Honda 2000 so I'm limited to about 13A of AC draw.)

I like separate units so a failure in one will not cause the loss of both functions. I get by with a 55A charger and a 1000W inverter, but could really use 1500-1800W. Having an inverter is like the movie Field of Dreams....build it and they will come. Once you have the 110V power available on the hook, you'll find more and more uses for it. I run an apartment size fridge on the inverter 24/7 on the hook and can power a coffee pot and a microwave. I have another small 400W inverter that I use on a countertop to provide 110V power to my computers and other portable devices.

I like the idea of a 4D start battery for both engines. I have an 8D that's overkill for a job that I'm confident a Group 31 could easily handle. Are you considering a multi-bank charger or using a combiner or isolator to charge the start bank? For years I had a multi-bank charger but when it died, I replaced it with a single bank charger for the house and use a combiner (selectable on/off) as needed occasionally to top off the start after it's been sitting for several weeks. Under normal use away from the dock, the start battery gets plenty of charge from the port alternator so no supplemental charge is needed.

I think your goal is very achievable for under $1000, especially if you get that Mastervolt for $400. That leaves $599 for an inverter and they can be found. Look at the RV sites for discounted inverters.

I am also on a budget and went with the Iota 55A smart charger for about $160. My 1000W Xantrex inverter cost about $120. I could buy both components 4 times and still be at about $1000.

Thanks guys, I looked at that Xantrex HF 1800, but it only has one charger output leg, and I will need 2.

Most of the sub $500 inverters appear to be "portable" units. How do you think one of those would do wired directly to the outlet bus on my AC electrical panel?

I'm kind of leaning toward just putting in a really good charger for now, overbuilding the battery bank, and adding a stand alone inverter at a later date.

You won't need a two bank charger if you use a combiner from Blue Sea or Yandina.

The charger in a decent inverter will be worlds better than even the best affordable stand alone charger.

I'd look at the Magnum brand of charger/inverters. Their model MM1212 should do what you want. If you can stretch your budget a bit their model ME 2012 would be even better.

If your AC loads are minor , TV , microwave and home cheapo fridge an under $200 1500W inverter from an RV or truck store is fine.

If you need to operate air cond , desalinization or scuba compressors a 4000W sine wave inverter will work best.

The small fish killers buy the best batt chargers with 4 outputs which can go to 4 individual (or pairs) of batts.

When ONE batt in a bank dies it will cause the std charger to overcharge the entire bank, usually killing them all.

A pro tournament 51034 is 4 batt 30A max $439 in defender,

the Pro Sport for 3 batts 20A is $189

Keeping the batts charged , and not overcharging can be as simple as you wish.

Capt.Bill11 said:

I'd look at the Magnum brand of charger/inverters. Their model MM1212 should do what you want. If you can stretch your budget a bit their model ME 2012 would be even better.

Click to expand...

The 1212 (1200 watt 12 volt) has a 70 amp charger and goes for $581 on Amazon and is listed for marine use.

MM Series Inverter/Charger - Magnum Energy, Inc.

the MM1512a (1500 watt) w 70 amp goes for about $720 to 750. Though I would want to check with them why it is not listed for marine use, just "alternative energy}

Agree the 2012 at $1119 would be great, with 100 amp charger. Add one their, or otheres mentioned already combiners / ACRs and you are within the combined budget described in the OP with a very high quality set up. Just not pure sine wave.

http://magnumenergy.com/me-series-invertercharger/

>I've honestly been waiting for the batts to go to make a change to a 6V house bank and a dedicated start bank (likely 1 4D to start both motors)<.

A series 31 or two would handle the start loads easily.

With no noisemaker 120V batt charging will be done at the dock , so large amperage is not needed as you have time on your side.

A $200 inverter and a stand alone 12V 10A batt charger might fit the bill, as long as it is not over a month between charges , and the freezer runs on 120V dockside.

The 12V deep cycle portable chargers with a 12 hour rotary on switch seem to work best as they will do a slight overcharge (todays best recommendation from the batt builders) .

Come back to the slip, turn it on and go home.

Thanks guys, I'm digging into these recommendations. Fred, we have a genset, a 8KW Kohler, we don't often don't come back to the dock at night, so I need at least 40 amp charging. I'm starting to think that I need more.

The Magnum look super interesting.

Doug

>so I need at least 40 amp charging. I'm starting to think that I need more.<

With an under 10KW noisemaker there is frequently a hassle that the charger will run at about half power .

To me the best solution is a truck alternator belted to the noisemaker ,

135A is under $150 , plus the cost of a marine brained V regulator.
3 or 4 stage with a temperature sensor will charge the house , very rapidly for even large battery sets.

With a SOC meter you will only need the dock for food, water, fuel and garbage.

A 8kw genset has 9600 watts. A 100 amp 12v charger at full output and typical conversion efficiency requires about 1800 watts max (that's the spec on the Magnum 2102, for instance).

>A 8kw genset has 9600 watts. A 100 amp 12v charger at full output and typical conversion efficiency requires about 1800 watts max (that's the spec on the Magnum 2102, for instance).<

Its not the rating in watts that feeds any electric device it is the power available from the wave form that does the work.

House current is not what a small noisemaker creates , regardless of KW rating , till one gets to 10KW or larger .

Most 120v devices will operate on small power, just as they will operate with cheap square wave inverter power.

That is simply not the case. I've seen first hand a 4kw on a Grand Banks we chartered drive 75 amps of charging just fine. I have seen little Honda gensets drive 40 amps. Modern chargers are extremely flexible in handling a wide range of voltages and incoming power forms and frequencies. If someone has an issue, it is due to the total load, (charger and other AC devices), being beyond the generator's capacity.