Need help with Pure Sine vs Modified Sine inverters

Our 1000 watt modified sine inverter wave needs replacing. Is there enough difference between pure and modified to warrant price variation.Pros /cons of each? What brands should I consider. We need only the inverter without a charger.THANKS David

Yes.

But they make great chargers for very little, sometimes no, premium.

Definitely recommend a pure sine wave as all electronic devices will be happy with it. Some don't like or won't run on a modified sine wave. Might want to stop and consider whether a larger unit might be beneficial for running something like a microwave.

I really like the Magnum Energy units which have a great programable battery charger built in.

Ted

The only thing I can add is that we will be happy to never own a Xantrex inverter/charger again! I'd go for the pure sine wave inverter but not a Xantrex...
Bruce

many appliances won't operate well using a MSW inverter. Some chargers will not only not work but will be ruined.

Given the life span of an inverter I suggest you buy pure sine wave and be prepared for more and more appliances which require pure sine wave.

Bruce B said:

The only thing I can add is that we will be happy to never own a Xantrex inverter/charger again! I'd go for the pure sine wave inverter but not a Xantrex...
Bruce

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Replaced an 18 month old Xantrex 40amp charger today. Talked to two buddies who are Certified marine electricians. One guy had replaced two near new Xantrex chargers in the last week. The other fella says he sees' the newer Xantrex chargers fail on a regular basis. My charger had a very small AC to DC leak right out of the box, in the megohm range so not going to do any damage bit both my buddies say that all the newer Xantrex units leak. My boat neighbour and pal just retired as president of IEEE, says there are design flaws in the Xantrex units.

NO MORE Xantrex on my boat !

boatpoker said:

Replaced an 18 month old Xantrex 40amp charger today. Talked to two buddies who are Certified marine electricians. One guy had replaced two near new Xantrex chargers in the last week. The other fella says he sees' the newer Xantrex chargers fail on a regular basis. My charger had a very small AC to DC leak right out of the box, in the megohm range so not going to do any damage bit both my buddies say that all the newer Xantrex units leak. My boat neighbour and pal just retired as president of IEEE, says there are design flaws in the Xantrex units.

NO MORE Xantrex on my boat !

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We had a factory installed Xantrex 2000 watt inverter charger fail after about 4 years...right before an offshore race...
Three replacements later we had a working replacement! The first two were DOA.
The third has been flawless but who wants to step into that mess again?
Bruce

"Xantrex" sounds like one of those post-modern crazy pills.

2 theories on inverters.....

Go expensive and hope for the best...and I agree that a pure sine and charger with 115v switchover is a great setup...till it fails...and in my experience and what I have read...that seems all too often. Many times with trouble or no help in getting it fixed.

The other is go cheap and have a spare or several and parcel out their duties. The only electrical/electronic piece of gear I have tried to use on a modified sine inverter that didn't work was my last computer printer....EVERYTHING else has always worked...maybe at reduced power...but never a big deal. That's over 20 years and almost 10 living aboard.

So roll the dice....

I retired a Xantrex and replaced it with two Magnum MS2812 inverter/charger. They have worked well. I would look at Magnum, MasterVolt or Victron. I would not install a Xantrex or ProMariner.

Sterling Power also has excellent products and very good support.

Pure sine only. There are now a lot of electric devices that just refuse to operate otherwise. Coffee makers seem to lead that list, but microwaves will either not operate or have short lives sometimes, some digital clocks won't keep accurate time, other electronics will just fail. More and more modified sine is facing obstacles. The newer and fancier the equipment the less likely that it can handle it.

Only go Pure!!
Three coffee machines, two electric blankets, one Samsung 34'LCD later I have learned my lesson.
And IMHO go as big as you can, you can run more stuff, boil the kettle, run the TV no problem, When underway the engines are replacing the charge.
Buy a good brand, not the cheap "to Good To be True" jobs from China, three inverters later ...I KNOW!!

"EVERYTHING else has always worked.."

The pure sine waves are required for heavy motor loads Water maker, Air cond .

The modifies seen to do well with almost everything else.

If the vessel will "live" off the inverter with mostly dirt house appliances the sine wave is needed.

Of its just for occasional use like a TV or microwave, blender ,coffee pot the $150 1500W the inexpensive units will do the job as well .

What service do you require?

HenryD said:

I retired a Xantrex and replaced it with two Magnum MS2812 inverter/charger. They have worked well. I would look at Magnum, MasterVolt or Victron. I would not install a Xantrex or ProMariner.

Sterling Power also has excellent products and very good support.

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Dunno if still the same, but apparently at one time most (all?) ProMariner and Sterling products were exactly the same units.

-Chris

I seriously consider buying a $2-$3000 inverter/charger all the time. My problem is about every time I go to do it... I hear of some cruiser having problems with theirs.

At $150 bucks, I can keep a spare or get one dang near anyplace along the loop....not so with the big boys and the Hassel with warranty issues too many seem to have.

Until I fry something or can't run something important while cruising that I like....I think I have my system the way it will be till one inverter company seems to have a break though in reliability.

Why are some of you running TV's on an inverter? 12 vdc TV's has been around since the early '70's.

psneeld said:

At $150 bucks, I can keep a spare or get one dang near anyplace along the loop....not so with the big boys and the Hassel with warranty issues too many seem to have.

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This is the direction I'm going with my off grid cabin. When you broaden your horizons to include 24 vdc it's amazing how little ac power is needed.

Stand on the dock and take a hard look at your boat. If it has a plate that says Nordhavn, Westport, Hatteras(you get the picture) buy a pure sine. If not well,,,, reconcile your mission with budget and buy accordingly. Walking through Costco yesterday I couldn't help but notice that you could buy about 15 32" TV's for the cost of a pure sine inverter.

Just fitted a new Magum mofdified sine wave, they had no pure sine waves in stock in Tortola. The freedom I had died after some 30 years approx.
The electrician recommended the Magnum (he used to be a agent for freedom /xantrex.

The only thing that does not work well on MSW is CRT type equipment. The new magnum runs all stuff on board including al the smart TV's and other smart equipment no problem.

I have an MSW 3000 watt Peak inverter.
Never would I buy a combo inverter-charger, my old Raritan converter does a good job still, it is from 1970.

Inverter has run everything, microwave, princess oven, PC, led TV, flourescent lights ok except for the 16k Cruisair heat pump.

Amazon.com: Peak PKC0AW 3000-Watt Power Inverter: Automotive

This company is now on its third iteration of that inverter. Comes with a wired remote switch.
My version looks like a double stacked inverter, inverter on top of another inverter.
I like PSW better, it works better with induction motors and transformers, otherwise, no difference.

I do like Samlex tech.
Mentions these are marine rated.

One advantage of PSW is the neutral wire can be grounded, MSW inverters split power onto both neutral and hot wires. This is not a problem wiring MSW into the wire system for a boat, but is for a house, since the house has a neutral to ground panel bond. One a boat, the gen also has a neutral to ground bond, but a twin pole (120vac), or multiple pole disconnect breaks all the connections to it.

Knurlgar24 has a lot of videos on inverters
https://www.youtube.com/user/knurlgnar24

Don't overlook Outback Power when considering inverters. I've found their gear to be very robust, though not the easiest to configure. But once it's configured, you are done.

I have to say I will NEVER again buy an inverter charger combo. While it is possible to configure your panel to accodominate and inverter-charger it gives me eye trouble, I just cannot see it.

I think you are far better served to have a good battery charger approiate for your needs and a separate inverter, separate circuits for inverter loads. No air conditioner, water heater for instance. And definitely PURE SINE WAVE, even if you have to limit or time your load in order to buy a less expensive, smaller inverter. For instance, do not run 2 hair dryers, a toaster oven and the microwave at once.

Mule said:

I have to say I will NEVER again buy an inverter charger combo. While it is possible to configure your panel to accodominate and inverter-charger it gives me eye trouble, I just cannot see it.

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What problems did you have?

Mule said:

... For instance, do not run 2 hair dryers, a toaster oven and the microwave at once.

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That should be easy! We don't own 2 hair dryers, a toaster oven or a microwave
Bruce

The big advantage of a sine wave/+charging unit is when the boat is created.

By specing a smaller noisemaker ( just enough to run two or three air cond as required)a far smaller unit can be installed.

The pass thru feature will take care of any instant overload from a heavy motor start, and the noisemaker will have a higher load in use than the monster "everything all the time" oversized unit.

For cruisers the ability to NOT start the noisemaker when at an out of the way marina with 30A or even just 15A , and continue their lifestyle is great!

The entire 120/240V electrical pieces and the DC portion are a System , and best viewed as one.

Not simply a pile of add on parts.

twistedtree said:

What problems did you have?

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I was not on board to see exactly what happened. The person there said he heard a loud buzz and a pop and down goes TV. I did not have my panel split properly and I suspect we lost shore power and the whole load hit the 3-8d's going through a auto switched mod pro mariner mod sine wave inverter. Air con, water heater was on the load.

Now I only use inverted power sparingly. All refrigeration, lights, fans and so forth is 12 volt. I have a Samplex 1.5 kW pure sine wave inverter that has 1 outlet. I have to manually plug into this separate circuit for inverted power. Really only used at anchor and load is closely monitored. Need more then I fire up the genset. AC and hot water is normally the only need because I have 1135 amps of stowage and 750 kW solar and 400 watts of wind.

Thanks for the update. There are lots of ways to go with inverter, and lots of ways to mess things up, create overloads, etc. But correctly installed with good equipment, they work great. I have a house with all the usual amenities, plus work shop with compressor and car lift, and everything is powered by a single 120/240V inverter/charger with solar as primary power source, and an 11kw diesel generator as secondary. The whole thing has never skipped a beat. And on my boat our 120V service is 100% inverter/charger powered with automatic passthru and charging when on shore or gen power. Nothing ever even blinks. And I'm in the process of extending the inverter service to a couple of 240V appliances.

So the concept is sound and reliable, provided you have good equipment and it's installed correctly. But there is also a lot of junk out there which is very tempting given its price. If you don't mind failures and replacement, the cheap stuff can work for you. Or you can belly up for a more robust system if your needs justify it.

Mule said:

I was not on board to see exactly what happened. The person there said he heard a loud buzz and a pop and down goes TV. I did not have my panel split properly and I suspect we lost shore power and the whole load hit the 3-8d's going through a auto switched mod pro mariner mod sine wave inverter. Air con, water heater was on the load.

Now I only use inverted power sparingly. All refrigeration, lights, fans and so forth is 12 volt. I have a Samplex 1.5 kW pure sine wave inverter that has 1 outlet. I have to manually plug into this separate circuit for inverted power. Really only used at anchor and load is closely monitored. Need more then I fire up the genset. AC and hot water is normally the only need because I have 1135 amps of stowage and 750 kW solar and 400 watts of wind.

Click to expand...

So the problem was that you didn't install it correctly. As someone who lived on inverter power 80% of the time in weeks, even months of full time living aboard on moorings and anchored, for several years, (let alone while underway) I found having a good marine inverter charger system to be invaluable, and one of, if not the very most reliable systems on board.

I have the Magnum Energy 2812 inverter charger and am happy with it. I leave the inverter switched to "off" unless I need to run an appliance or some AC lighting.


Jim
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Another H U G E fan of Magnum. I have an 80 amp Charles charger. I was looking for a PSW stand alone inverter in the 2000 watt range. Unless you want to go Xantrex or other cheap stuff, there just isn't any decent stand alone powerful PSW inverters. So I have a 120 amp charger with a 2000 watt inverter. Do it right. Do it once. Be done with it. I never thought I would have an emotional attachment to a piece of electrical equipment, but I love the thing. And let's not forget. If you like your batteries, the Magnum is a 4 stage charger. The fourth stage being a resting stage where there is no charge on the batteries. The charger/BMK monitors the bank and will re apply the float charge if needed. A continuous float charge can theoretically be harmful to batteries over time. Anyway, my point being is, while you are not looking for a charger, you get one as a bonus. And in the Case of the Magnum Energy unit, a damn good one!!! The programmability of the Magnum is a huge plus as well...both on the inverter side as well as the charging side.

PS....a Xantrex PSW 1800 watt inverter only is almost the same price as the Magnum 2000/120amp inverter charger. And the Magnum is a SIGNIFICANTLY better unit!!!

PSS...I keep the Charles Charger off unless I really drained the batteries and need lots of charging power. Then it can work in tandem with the Magnum.