Pure vs modified sine wave inverters

[Mat7783]

I would imagine that a pure sine wave inverter is more efficient that modified. Could someone please educate me on the advantages. Thanks😎

[Ninjakitty]

Many electronics work better with a pure sine wave. Computers, refrigerators, etc...

[Dead pirate]

Feed back with a modified. So anything with sound is affected. It causes a whine.

[Mat7783]

Got it. Makes sense. Thank you!

[Johnny Mullet]

Pure sine is the way to go.

[john61ct]

There are load devices happy with MSW so can save $ if buying for only that.

Could have a MSW circuit and a PSW circuit.

Makes a huge difference if spending thousands on quality gear only when necessary, Magnum and Victron at 3kW add up fast.

[farok]

Is there a list of things somewhere that are known to work fine with modified sine wave output? I've always been unclear on what will work and what won't. I know my laptop would want pure sine wave output, but for $25 I can get a direct DC adapter and bypass the DC-AC then AC-DC power brick, so that's not a concern for me.

Chris

[brokedown]

As others have mentioned, PSW is "better" for some loads... But I'd say that from a practical standpoint, it's not that important. Are you running your 1970s HiFi stereo system in your bus? Probably not. If you're paying attention, you're using dc whenever possible and AC when alternatives aren't available. Big refrigerators, air conditioners, instant pots...If you're charging your laptop/tablet/phone from an AC charger you're wasting more power than you're putting into your battery.

Someone on another site put it like this: Would you spend an extra $1000 on an inverter to maybe add 10% to the life of a $400 refrigerator? My $80 1000W MSW unit has been great.

[Mat7783]

I plan on using propane fir stove , water heater, and portable heat. 120vac will be for 7.3 cu’ fridge and 700W microwave and occasional hair dryer and a couple of outlets fir little things.all lites and water pumps on 12vdc. That’s why I was looking at 3kw inverter and 400ah battery bank. Will use inverter generator or RV camp power to recharge batteries. Dies this sound practical on the surface??

[PNW_Steve]

Pure wine wave is definitely the better choice and good ones are not that much more expensive.

That said, I lived with a modified wine wave in my first bus for 6+ years on the road with no trouble.

20+ years ago the PSW were quite expensive compared to MSW.

Today I have a couple of Trace PSW and a Xantrex PSW. The quality stuff is not horribly expensive like it used to be.

[john61ct]

But if you only need say 250W for one gadget and MSW is good enough, it can be pocket change, carry spares

And so much more energy efficient when the inverter gets turned on and off with the device, it's leaving them on all the time that sucks the bank dry.

As well as matching the size to the load.

Sure the "standby mode" can get super low on the pricey ones, but running a 200W load off a 2000W inverter can like double the DC amps rate.

Personally I avoid them completely as much as possible try to go all-DC as much as possible.

But then I'm happy living off grid without vacuum cleaner, laundry machine / dishwasher, microwave, electric*stoves, toasters, blenders, ice makers,*etc

[dzl_]

Originally Posted by farok

Is there a list of things somewhere that are known to work fine with modified sine wave output? I've always been unclear on what will work and what won't. I know my laptop would want pure sine wave output, but for $25 I can get a direct DC adapter and bypass the DC-AC then AC-DC power brick, so that's not a concern for me.

Chris

The basic rule I've always heard is that Pure Sine is preferred for (1) sensitive electronics (2) some types of motors (think power tools, fridges, etc).


Here is a bit more info:



This isn't quite a comprehensive list but its a start
And another partial list

[dzl_]

More info:
https://www.magnum-dimensions.com/kn...equency-vs-low


edit: oops forgot we were talking about pure vs modified not LF vs HF