Modified vs Pure Sine Wave

Re: Modified vs Pure Sine Wave

Many things will work perfectly well on MSG throughout their normal expected lifetime. A few items however, using designs that work perfectly well on normal grid power, don't like MSW and some critical internal parts will overheat to the point of being destroyed. Which items will work fine and which will fail is sort of like playing Russian Roulette. You basically have to risk it, try it, and see what happens.
Other things are known, like the fact that induction motors can draw roughly 18% more power, resulting in raised temperatures which may cause damage, but will definitely waste power. These raised temperatures can be critical to refrigerator and freezer compressors and have been known to cut short their lives. There is another motor problem, and that's the excess vibration in the windings caused by sharp pulsing of the magnetic fields caused by the MSW, a vibration that can wear down the insulating within the windings, resulting in shorted windings.
So it depends on what use the MSW is put to whether the results will be fine - - or not.
In the past, before I switched to pure sine, I did burn out the power supplies in the electronics of two bread makers, and found that rechargeable drills would not recharge properly. Other than that, there were no problems.

Re: Modified vs Pure Sine Wave

I read a study done by a major computer magazine in the early-mid 90's, where they tested dozens of computer power supplies with all kinds of dirty power. Too high, too low, off-frequency, pulsed, etc. No issues. Now-a-days most consumer electronics (tvs, dvrs, stereos) have either the same type or switching power supplies, which will take anything short of a lightning strike.

Personally the only thing I found that almost fried on MSW was an X10 controller. Others have mentioned problems with shavers.

Re: Modified vs Pure Sine Wave

Steven Lake wrote: »

Is there any kind of line conditioner plugins you can put between a MSW inverter and your item in question to soften the signal from MSW to pure, or at least something less "water hammerish" in its nature?

You could use a bank of batteries with a charge controller and a sine wave inverter....

Re: Modified vs Pure Sine Wave

When I bought my inverters I thought about it a bit and decided I'd rather shell out a bit more for the PSW models and KNOW I'd be fine than save a few bucks on MSW, worry about my more expensive items, and possibly even have to repurchase something that went out early because of it.

Most of the items I'm running on inverters cost more than the difference in price anyway. (I wouldn't buy the Really Cheap junk even if I did go MSW.)

Re: Modified vs Pure Sine Wave

mike95490 wrote: »

Nope, either they are ineffective, or so effective they crash the inverter which can't handle the inductive load. Better to get
the pure sine inverter and rest easy.

Exactly! Everything else is either impractical or tantamount to snake oil.