Pure Sine Waves: Really?

feedhornfeedhorn Solar Expert Posts: 103 ✭✭
I've used Modified Sine Wave inverters for many years and never found a single electrical product that was bothered by them so I can't see any reason to buy the more expensive SW inverters.

Please spare me the marketing hype, I've heard all that over and over.

Tell me what appliances really need pure sine waves so I can justify lower efficiency and higher cost SW inverters.

Thanks,

Comments

  • jcheiljcheil Solar Expert Posts: 722 ✭✭✭
    Re: Pure Sine Waves: Really?

    It's not marketing hype. There really is a difference.

    The experts here can explain the exact electrical differences/consequences/reasons for this but one of the most obvious ones is that motors (including those in compressors) will buzz and run hotter and heat is the leading cause of premature failure of electronics.

    Small battery chargers for some cordless tools like Dewalt/Ryobi will cause the batteries to fail much sooner if use on modified sine-wave inverters. Some will even destroy the battery immediately.
    Off-Grid in Central Florida since 2005, Full-Time since June 2014 | 12 X Sovello 205w panels, 9 X ToPoint 220w panels, 36x ToPoint 225w panels (12,525 watts total) | Custom built single-axis ground mounts | Complete FP2 Outback System: 3 x FM80, 2 x VFX3648, X240 Transformer, FLEXnet-DC, Mate-3, Hub-10, FW500 AC/DC | 24 x Trojan L16RE-B Batteries 1110ah @ 48v | Honda EU7000is Generator and a pile of "other" Generators | Home-Made PVC solar hot water collector | Custom data logging software http://www.somewhatcrookedcamp.com/monitormate.html
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Pure Sine Waves: Really?

    You need to look at them through an oscilloscope and understand what the difference in waveform means to how loads operate.

    Induction loads, which pull peak current at a point in the wave other than the Voltage peak, benefit the most because the curve isn't as distorted on pure sine (THD <5% as per utility power spec) to begin with.

    In operational terms there are two things to remember: First, not all MSW outputs are alike. Some are very poor quality square waves, others have multiple steps of varying widths which more closely approximate sine. Second, the difference between MSW and sine will not usually show up as instant death of the load but rather poor performance; drawing more current, heating up more, and having a shorter lifespan than it should.

    So the refrigerator starts, but it clatters when it does because the motor is working harder. The battery charger functions, but it puts out more heat and cooks its components cutting down their life. The clock runs, but it loses minutes per day.

    The worst of it is you never know in advance whether the load will work good enough on MSW or work poorly or age fast ... or burn up in an instant.
  • waynefromnscanadawaynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Pure Sine Waves: Really?

    I too started out with MSW inverters and indeed most things did operate more or less OK - - - however induction motors did emit buzzing sounds while running on the Modified Square Wave, my Kill-A-Watt meter ran with a hot spot on the side where heat and the smell of overheating internal parts escaped, cordless drills would not properly recharge, in fact one wouldn't charge at all, and two bread makers had their electronics emit smoke and die.
    Being new at the time to the off-grid world, I argued with those who tried to explain how induction motors would suck back roughly 15% more power running on Modified Square Wave (Modified Sine Wave is a marketing term used by those selling such inverters to make them sound much better than they are). I too at that time didn't see the necessity of spending the extra money, I'd just avoid using items that didn't like MSW.
    Eventually however I came across a Morningstar 300 watt TSW inverter at a good price and was very pleased with the quality of the power it produced. So pleased in fact that I ended up with two of them. Several items I had suddenly sprouted two power cords each, one to connect to a TS300 and supply power for the electronics, the other to supply power from the more powerful MSW inverter I had, to the motors and heating elements of breadmakers, etc. This worked quite well, but was a pain in the butt as still there was the water pump and other items buzzing along on MSW. I could hear the windings vibrating, and as I had been warned, imagine chafing through the insulating varnish somewhere and ending the motor's life, could imagine early failure of the freezer etc. Having had several MSW related failures and finally accepting what was going on, a 1800 watt Pure Sine inverter was purchased, and after living with Pure Sine for over 5 years now, the only way I'd go back to MSW would be for emergency use. Gone is the worry, gone are any problems at all with any item I wish to power, gone is the buzzing from motors. Yes, the inverters I now use do consume a bit more power to run, but that may well be made up for with lower consumption by the water pump, two chest freezers and the fridge.
    In closing, yes, MSW inverters do have their place, but they're no longer supplying power to my house. Their use was a learning experience for me.
  • john pjohn p Solar Expert Posts: 814 ✭✭✭
    Re: Pure Sine Waves: Really?

    Feed horn.. clocks will work badly on MSW inverters so will many types of motors.. Many plug pac .. ie cell chargers will go up in smoke so will nebulizers.
  • feedhornfeedhorn Solar Expert Posts: 103 ✭✭
    Re: Pure Sine Waves: Really?
    : First, not all MSW outputs are alike. Some are very poor quality square waves,

    Yep, some 40 year old Radio Shack inverters put out square waves. Can you show me any modern ones for sale today?

    BTW: I do have an oscilloscope and I know what the waveforms look like.

    Can you name any current products that can't handle MSW?
  • feedhornfeedhorn Solar Expert Posts: 103 ✭✭
    Re: Pure Sine Waves: Really?

    Ah Yes, I remember, that old type of motor they used in record players. It might operate poorly on MSW.

    Does anyone have an old record player they can test running on an MSW inverter? Does it run the right speed?

    Give it a test.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Pure Sine Waves: Really?
    feedhorn wrote: »
    Ah Yes, I remember, that old type of motor they used in record players. It might operate poorly on MSW.

    Does anyone have an old record player they can test running on an MSW inverter? Does it run the right speed?

    Give it a test.

    No, it is not just some old record player motors.

    Nor is it some old Radio Shack inverter that is the only one outputting square wave. If you take the time to actually read the huge wealth of real-world information on this forum you will find among other things some waveform prints courtesy of TooManyToys (unless the post got lost in the 'upgrade' that did so much damage).

    In fact it would be a good idea if you read more instead of assuming you know everything already based on your extremely limited experience. We have real electrical engineers here and many people who have decades of experience with electronics and power systems, myself included.

    Surprisingly, I have not personally tested every single one of the thousands of inverters out there nor every single possible load someone might try to run from it. You've had input but you choose to ignore it because it doesn't fit your preconceived notion that MSW works for everything and sine wave is just hype and extra expense. This is similar to your ridiculous contention that lead-acid batteries don't work for RE. So far you've only succeeded in making yourself look foolish.

    If you continue with this "you people with all your education and experience don't know what you're talking about" attitude you'll be doing it elsewhere. Consider that a warning.
  • ramlouiramloui Solar Expert Posts: 103 ✭✭
    Re: Pure Sine Waves: Really?

    My miter saw worked on MSW but not the variable speed jigsaw.
    Off-grid cabin in northern Quebec: 6 x 250 W Conergy panels, FM80, 4 x 6V CR430 in series (24V nominal), Magnum MS4024-PAE
  • BB.BB. Super Moderators, Administrators Posts: 29,482 admin
    Re: Pure Sine Waves: Really?

    There are (or where) square wave inverters. +120 volts for 1/2 cycle, and -120 volts for 1/2 a cycle.

    Then there are modified square wave (some marketing types call them modified sine wave). On to ~+130 volts, off to zero volts, on to -130 volts.

    And there is the sine wave inverter, obviously a sine wave that goes + to - 170 volts peak.

    For AC induction motors (non-brush/universal motors), they "like" TSW (true sine wave) because they need a "rotating field" to operate. That field is (for a 2 pole motor) running at 60 Hz * 60 seconds/min = 3,600 RPM. All of the electrical energy (in a sine wave) is at the fundamental rotational speed of the motor.

    When you run a SW or MSW inverter, something like 20% of the electrical energy (for MSW as I recall) is not at 60 Hz, but at higher frequencies. It can be look at as a bunch of sine wave added together to give you the MSW wave form:

    Attachment not found.

    These "odd harmonics" cannot "do work" in the Induction Motor--But their energy has to go "somewhere"--And that somewhere is usually as heat (more current through wiring, circulating currents in rotor and pole plates, etc.). So, a motor will take ~20% more power on a MSW inverter vs a TSW inverter. If the motor is "over-sized", not much of an issue--It will get a little hotter and dissipate a bit more heat. If the motor is designed for the application and/or has poor abilities to dissipate the extra heat (say a compressor in a refrigerator), it will run hotter and potentially fail sooner.

    For things like a "typical" computer/electronic power supply... The MSW wave form also presents issues. First, notice that the peak voltage is lower for a MSW wave form vs a sine wave. The lower peak voltage will sometimes cause the power supply to not function well, or at all. Many of these "simple" AC to DC supplies use a diode and high voltage capacitor. The diode charges the capacitor to the "peak" line voltage, and then the capacitor holds the energy for the DC converter side to down convert to the needed voltage/current. Too low of input peak voltage can cause "brownout" like conditions in the supply.

    Also, a sine wave has nice smooth ramp/transition between the +/- peak voltages. The peak current it kept "relatively low" because of this. MSW inverters have "square side". Current flow goes from zero to high on these edges. These high current peaks cause excess heat inside the supply because of I2R heating... If the peak current doubles, the heating goes up by a factor of 4x (because of the square function).

    For many small/cheap power supplies, this can cause actual overheating/melting of the AC side of the power supply.

    There are other "tricks" used to make cheap power supplies that don't play well with MSW inverters... These include the use of a small capacitor to only let a "little amount" of energy through to the DC regulator. This is (or was) used by the Kill-a-Watt meter. On sine wave input the amount of current was limited because of the slow transition of the sine wave shoulder. For MSW, the sharp/near verticle wave front allowed the capacitor to pass more current that designed, which caused the ballast resistor to over heat in 5-10+ year old Kill-a-Watt meters and fail (newer KaW meters have been redesigned).

    And with AC transformers--Similar issues. They are designed to pass relatively low frequency power (50 or 60 Hz). The high frequency power (180 Hz, 300 Hz, etc.) usually causes circulating currents in the iron plates of the transformers--Causing them to run hot (and if they are in front of diode+capacitor based switching power supplies, the peak current increases too--more heating). Put these in a small plastic box (plug into wall, bump in power cord)--And you have over heating power supplies for small consumer electronics.

    This not say that everything plugged into an MSW inverter will "blow up"... Probably 80% will work fine, 10% will fail (sooner or later), and another 10% may die an earlier death than they would have otherwise (for every 10C increase in operating temperature, life is cut by 1/2--An old engineering rule of thumb based on material sciences, 20C increase: 1/2*1/2=1/4 life).
    [h=4]Choosing an Inverter - Home Power Magazine[/h]Yes, there are many folks using well designed MSW inverters out there and very happy with them. If price is important to your design/bank account, an MSW inverter can meet your needs.

    However--There will be some loads that may not work well (typically less expensive/mass market/high volume consumer times) on MSW (small cell phone, computer power supplies; CFL lamps, etc.) because of the wave form and/or because of the "low" peak voltage. If your loads work well on your MSW inverter--That is wonderful.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • loreleclorelec Solar Expert Posts: 200 ✭✭✭✭✭
    Re: Pure Sine Waves: Really?

    It's important to differentiate between a simple square wave inverter (which has a lot of harmonic distortion) and the typical MSW inverter (which has eliminated many of the harmonics - most importantly the third harmonic, which contains much of the energy that must be dissipated in a motor designed to run on a sine wave). It's also interesting to note that many commercial motor drives rely on square wave PWM to control motor speed....and that mechanical failures can result from the additional stress caused by driving them with square waves. In any case, motor failures on MSW - if they occur at all - would very likely not be immediate, but years down the road.

    Probably the single most common failure from MSW occurs in devices that use triacs or SCRs to gate the incoming waveform - to control light dimming or battery charging, for example. I've used an old MSW inverter for at least a decade now in the house, and the only failure I've ever witnessed on it was a cordless drill battery charger. And I run a large variety of stuff from it.

    MSW inverters are electrically (and often audibly) much noisier, too, which can be a problem with audio and sensitive test equipment.
  • mike95490mike95490 Solar Expert Posts: 8,369 ✭✭✭✭✭
    Re: Pure Sine Waves: Really?
    feedhorn wrote: »
    ...Can you name any current products that can't handle MSW?

    I'd suspect many large motors, like my well pump, and it's starting cap, will NOT like MSW. And folks reported here, that ceiling fans buzz a lot on MSW.
    Generally, the $30 MSW inverters, have about 3 steps in their waveform, some MSW inverters have 50 steps. So there is much variation in the MSW designation.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
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  • SusidoSusido Registered Users Posts: 32 ✭✭
    Re: Pure Sine Waves: Really?

    Been using a MSW inverter for about 7 years now so I'd say I do have some experience in the matter. I've encountered one piece of equipment which would not work - an electric blanket. Everything else has worked perfectly fine as far as I can tell. Well pumps, electronics of every description, battery chargers, tools, everything I've ever plugged in has worked just fine - except that damn blanket. Well I also discovered you can't charge another MSW inverter/charger using the output of a MSW inverter...

    I know this forum has many posters with strong opinions against MSW inverters. And that's fine; if a 2500 watt pure-sine wave inverter/charger was anywhere near the price of my Tripp-Lite when I bought it, I would definitely have bought that instead. And if this one ever dies, I probably will replace it with a pure sine wave inverter for peace of mind and better efficiency. Maybe I've been unwittingly slowly destroying everything electrical I have because of MSW and just haven't had anything fail in 7 years?

    Speaking of efficiency, microwaves are kind of a unique scenario. It takes about 40% longer to heat using a MSW inverter but that could be considered an advantage because that translates to less of a hit to the battery bank (peukert's law). And as long as you aren't using a Panasonic microwave with "inverter technology" they seem to work just fine despite some unpleasant noises.
    Seasonally off-grid ... 468 Ahrs @ 48V (8 Rolls S-605 6v FLA batteries),  24 x 130watt panels, 6 x 260watt panels, 2 x Midnite Classic 150, Whizbang Jr., Magnum MS4448PAE inverter/charger, 2 x Honda eu2000i generators paralleled.


  • SolarPoweredSolarPowered Solar Expert Posts: 626 ✭✭✭
    Re: Pure Sine Waves: Really?

    Quartz drive motors, and most inductive motors will have half a life span on MSW.

    Most battery management systems for LAPTOP PC's converting AC to DC fry the batteries, or the actual mother boards to the laptops. I've gone through 3 laptops in 2 years working from my truck using 200watt MSW inverters, I won't do it any more. Ever since pure sine wave had the same laptop for 3 years.

    Also MSW inverters are less efficient and will drain batteries faster than PSW inverters. It takes more power delivery from MSW to power the same equipment than using PSW.

    I've noticed on a 12V deep cycle 10Ah battery that MSW will drain the battery approximately 7% faster than the PSW. PSW operate at a range of 90% or higher while MSW operates under 90%. Regardless equipment by design requires a demand of Volts X Amps = Watts and the more fluid, linear, and smooth the efficiency is of that inverter translates to uninterrupted operation.
  • waynefromnscanadawaynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Pure Sine Waves: Really?
    Quartz drive motors, and most inductive motors will have half a life span on MSW.

    Most battery management systems for LAPTOP PC's converting AC to DC fry the batteries, or the actual mother boards to the laptops. I've gone through 3 laptops in 2 years working from my truck using 200watt MSW inverters, I won't do it any more. Ever since pure sine wave had the same laptop for 3 years.

    Also MSW inverters are less efficient and will drain batteries faster than PSW inverters. It takes more power delivery from MSW to power the same equipment than using PSW.

    I've noticed on a 12V deep cycle 10Ah battery that MSW will drain the battery approximately 7% faster than the PSW. PSW operate at a range of 90% or higher while MSW operates under 90%. Regardless equipment by design requires a demand of Volts X Amps = Watts and the more fluid, linear, and smooth the efficiency is of that inverter translates to uninterrupted operation.

    Although I used only MSW inverters for a number of years, running everything from a deep well pump and fridge, to computers etc, and now only power these items from pure sine, and wouldn't willingly go back to MSW, your findings / reports were not my experience, which was definitely not as negative as yours.
    I did smoke a couple of breadmakers on MSW, a Kill-A-Watt overheated and some cordless items wouldn't charge, but never had any problems with computers, including full sized power gulping pigs, high efficiency lap tops and several TVs, all of which, for whatever reason, handled MSW with apparent ease. Perhaps the difference was in the design of the MSW inverters. As some have noted, not all MSW inverters are the same.
    As to MSW inverters draining batteries faster than PS, until I finally got my mini-micro hydro going, I used to switch from PS to a similar sized MSW during the dark days of Fall and early Winter as it's tare consumption was dramatically lower. Consumption was however higher when running induction motors on MSW, as they put a greater demand on MSW power supplies than they do on PS.
  • SolarPoweredSolarPowered Solar Expert Posts: 626 ✭✭✭
    Re: Pure Sine Waves: Really?
    Although I used only MSW inverters for a number of years, running everything from a deep well pump and fridge, to computers etc, and now only power these items from pure sine, and wouldn't willingly go back to MSW, your findings / reports were not my experience, which was definitely not as negative as yours.
    I did smoke a couple of breadmakers on MSW, a Kill-A-Watt overheated and some cordless items wouldn't charge, but never had any problems with computers, including full sized power gulping pigs, high efficiency lap tops and several TVs, all of which, for whatever reason, handled MSW with apparent ease. Perhaps the difference was in the design of the MSW inverters. As some have noted, not all MSW inverters are the same.
    As to MSW inverters draining batteries faster than PS, until I finally got my mini-micro hydro going, I used to switch from PS to a similar sized MSW during the dark days of Fall and early Winter as it's tare consumption was dramatically lower. Consumption was however higher when running induction motors on MSW, as they put a greater demand on MSW power supplies than they do on PS.


    I've come to find out that not all the MSW's are alike in their operation capabilities, where as the tolerance or specs for the PSW inverters are much tighter on specification. Now when I was burning laptops I went from Black and Decker to Husky MSW from home depot. All made from china and all loosely based specifications, as well the frequency responses aren't as consistent or tightened within the specifications that PSW inverters are designed to do.

    You can get a PSW with a tolerance of +/- 5Hz of 60Hz or better, where as with the MSW the tolerance can be greater than +/- 10Hz of 60Hz or better. I believe this is one of the many Battery draining issues, and inefficiences with MSW.

    I agree with your statement based on tare consumption/standby. Look at the big picture MSW motherboards are smaller, and use less components so I have seen them draw as much as .05% at tare where asd PSW's are higher around or up to 2%. In my mind what really matters is peak surge power and how efficient the sine wave can perform under that peak surge because that is where the most ineffciency and consumption come from.
  • techntrektechntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Pure Sine Waves: Really?

    I tested a X10 controller on a MSW inverter I have, and within seconds it got very hot and started to smell, so I unplugged it immediately. It was ok in the end but obviously it would have died quickly if I let it go.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • CDN_VTCDN_VT Solar Expert Posts: 492 ✭✭✭
    Re: Pure Sine Waves: Really?

    I have had a few MSW make the GFI Receptacles Buzz , & they have had time starting florescent cold start ballast . My last good MSW xantrex 1200 plus inverter smoked because I forgot to float the neutral .. I needed a PSW for a test & pulled a SS300 hoping to use the Xantrex . Pop went the soldered in fuses 2 30A of four. I spent a few hrs trying to repair , after new fuse terminals were soldered in for replaceable fuses , the smoke was let out of many heat sunk SCR's .. SCRAP !!!

    Who has had any luck with the off shore PSW brands in 2000-2500w .. Can't justifie 1800.$ over 400 off shore for are needed for for testing in building storm retreats .

    VT
  • Mountain DonMountain Don Solar Expert Posts: 494 ✭✭✭
    Re: Pure Sine Waves: Really?
    feedhorn wrote: »
    Can you name any current products that can't handle MSW?


    I guess it depends on how one defines "can't handle MSW". I have tried a few different brand MSW inverters with two different small microwave ovens we have. One at our cabin the other in a travel trailer. Both microwaves made a lot more noise. Both microwaves took considerably longer to heat the same volume with the same starting temperature. (It was a while ago that I did the tests and I can not recall exactly, but it was considerably longer; 30% or more) I guess I expect things to work the same way as they do when plugged into the wall at home. So in my view these two microwaves can't handle MSW. TMMV.
    Northern NM, 624 watts PV, The Kid CC, GC-2 batteries @ 24 VDC, Outback VFX3524M
  • ILFEILFE Solar Expert Posts: 364 ✭✭
    Re: Pure Sine Waves: Really?

    I look at it like this. If you use MSW inverters and are happy with them, then I am happy for you. Ecstatic. Great. Wonderful. Woo Hoo! But, for me, not gonna happen.

    I will never use another MSW inverter again, with the possible exception of an urgency arising. Then, it would only be until I could get another PSW inverter. I lost two stand fans due to plugging them into MSW inverters, early this year. (The sound of the motors running is also quite different from when they are being properly powered by PSW electricity.) I had another MSW inverter overheat and shut down, while powering a one-third total capacity load.

    I will be back in the US late this year, until early Spring of next. During this trip, I will have two MorningStar SureSine (SI-300-220V) 12vdc inverters delivered to me. I will bring them back to Cambodia to be used on my solar arrays here. While I am not crazy about MorningStar's customer service, I have to admit, I have only heard positive reviews of these inverters. (I can vouch for the quality of a couple of their PWM controllers too.)
    Paul
  • waynefromnscanadawaynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Pure Sine Waves: Really?
    I guess it depends on how one defines "can't handle MSW". I have tried a few different brand MSW inverters with two different small microwave ovens we have. One at our cabin the other in a travel trailer. Both microwaves made a lot more noise. Both microwaves took considerably longer to heat the same volume with the same starting temperature. (It was a while ago that I did the tests and I can not recall exactly, but it was considerably longer; 30% or more) I guess I expect things to work the same way as they do when plugged into the wall at home. So in my view these two microwaves can't handle MSW. TMMV.

    My cousin found the same thing with the small microwave on his boat. Supplying the micro oven from a 1700 watt MSW, it took roughly 3 times longer than when operating on grid power to heat things, very slow indeed.
  • CALLDCALLD Solar Expert Posts: 230 ✭✭
    Re: Pure Sine Waves: Really?

    I had a modified sine wave inverter before finally giving in and getting a PSW. It was a 1200watt long-run UPS. Not sure what brand it was but Inverex inverters looked very similar. It was cheap, performed well, running everything I put on it that was under the max load. It just made the fan buzz which annoyed me. The frustrating thing for me was that I don't have an oscilloscope, because I would have loved to see the wave form! finding info on its waveform was impossible, the manufacturer wouldn't say anything, neither would any reviews. I suspect it wasn't a typical stepped wave, I've had one of those inverters before that I bought at an autostore. It was rubbish, could hardly run anything, it was as if the voltage was too low! This one however ran everything, and it seemed to react instantly to surges. I suspect it used PWM voltage regulation, and in fact I think the waveform was a simulated sine wave with a decent resolution using PWM technology. It would probably have looked like a fuzzy square wave on an oscilloscope.

    I don't see any problem with using such a MSW inverter, but pure sine wave is obviously better.

    Just be careful, the first PSW I bought I had to return, the high frequency used to generate the sine wave wasn't filtered adequately in the inverter and would cause my iPhone to freeze when I plugged in the charger, various other electronics didn't like the high frequency interference either - for example my satellite TV decoder didn't respond to the remote signal and the TV had a fuzzy picture. Try before you buy when it comes to PSW inverters! The one I have now, a no-name brand PSW runs everything perfectly but the one drawback is it doesn't respond as quickly to surges, there is a noticeable voltage sag for a split second while the inverter reacts. There is also a window of loads between 120 to 400watts where the voltage isn't that stable, fluctuating by about 5% which is enough to make LED lights flicker. If you don't want this to happen then you have to get a high quality expensive inverter with a reputable brand name.
  • CDN_VTCDN_VT Solar Expert Posts: 492 ✭✭✭
    Re: Pure Sine Waves: Really?
    ILFE wrote: »
    I will have two MorningStar SureSine While I am not crazy about MorningStar's customer service, I have to admit, I have only heard positive reviews of these inverters. (I can vouch for the quality of a couple of their PWM controllers too.)

    I purchased one of these in the 60hz 120 V Paul , on the first trial of the unit the smoke was let out. I called Morning star tech line , gave them my Serial # and a new unit was sent within a week. They had a batch of problem ones i was told & three years ago when this happened ,the tech also said they were going to release a larger size unit .

    I thought there customer service was fine , never saw any larger unit from the Morningstar group. I did read that Mignight is starting on this avenue also.
    Reading CALLD I might pick up a offshore PSW for the barn. 300w is just not larger enough
    VT
  • ILFEILFE Solar Expert Posts: 364 ✭✭
    Re: Pure Sine Waves: Really?
    CDN_VT wrote: »
    I purchased one of these in the 60hz 120 V Paul , on the first trial of the unit the smoke was let out. I called Morning star tech line , gave them my Serial # and a new unit was sent within a week. They had a batch of problem ones i was told & three years ago when this happened ,the tech also said they were going to release a larger size unit .

    I thought there customer service was fine , never saw any larger unit from the Morningstar group. I did read that Mignight is starting on this avenue also.
    Reading CALLD I might pick up a offshore PSW for the barn. 300w is just not larger enough
    VT

    Do you still use the replacement unit you were sent? How would you say it has performed for you? Another member on this site has two of them, I believe? I know Mike has one and has had only good things to say about it as well. Members of other forums, the same. To be honest, 300 watts is probably a bit low for me. But, I figure I can make do with them for now. If necessary, I will use both at the same location.

    Regarding their (MorningStar's) customer service, it was regarding controller questions. They just made me feel as though they didn't have time to talk with me. I was calling internationally, so it wasn't like I wanted to remain on the line any longer than necessary, either. :roll:
    Paul
  • CDN_VTCDN_VT Solar Expert Posts: 492 ✭✭✭
    Re: Pure Sine Waves: Really?

    I bought the unit from here & called here NAWS first , they gave me the numbers to call & told me who to ask for etc. Replacement unit has made me buy 2 more . One as spare backup. For the price , they are expensive against MSW junk but have few flaws. The flaw I had with one was it would no go into sleep mode while I had a Kill-a-watt plugged in (i later found) .. My Flaw :-) .. If you overload it , it cuts off , fusses are replaceable , unlike my Xantrex that i picked up used.I need to buy a inexpensive 1500w PSW unit that's used in a storm cabin that's never locked , that's my quest. I know the Bears & Cats won't take anything that tastes bad , but 2 legged squach are the ones to watch out for.
  • ILFEILFE Solar Expert Posts: 364 ✭✭
    Re: Pure Sine Waves: Really?
    CDN_VT wrote: »
    For the price , they are expensive against MSW junk but have few flaws.

    I don't think they are too costly. I found a company that stocks the 220v / 50hz units for $202 USD, each. Domestic shipping for one is under $17 USD. Shipping for two units is under $20 USD. I don't think I can beat that with a stick.

    CDN_VT wrote: »
    The flaw I had with one was it would no go into sleep mode while I had a Kill-a-watt plugged in (i later found)

    I will keep that in mind, not to keep my power meter plugged into them.

    Note to self: Buy extra fuses while in the states.
    Paul
  • mike95490mike95490 Solar Expert Posts: 8,369 ✭✭✭✭✭
    Re: Pure Sine Waves: Really?

    I have one (SureSine 300) that's been running 24/7 for 4 or 5 years now.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • soylentgreensoylentgreen Solar Expert Posts: 106 ✭✭
    Re: Pure Sine Waves: Really?

    My van has a MSW inverter and I've noticed that my iDevice chargers all run crazy hot on it. That can't be good.
  • ILFEILFE Solar Expert Posts: 364 ✭✭
    Re: Pure Sine Waves: Really?

    soylentgreen,

    Sorry to go off topic. But, every time I see you post, I think of the movie. God, that was a weird one.
    Paul
  • CDN_VTCDN_VT Solar Expert Posts: 492 ✭✭✭
    Re: Pure Sine Waves: Really?
    My van has a MSW inverter and I've noticed that my iDevice chargers all run crazy hot on it. That can't be good.

    Yup your doing damage !
    Who can say a good inexpensive PSW 1500 offshore inverter would be worth looking into ?
    I do buy lots of stuff here , but for shelters , I'm not putting in a grand of inverter , the CC is well hidden , panels are HUGE to move . I'm not saying things walk , but I would rather hedge the bet.

    VT
  • creekycreeky Banned Posts: 31
    Re: Pure Sine Waves: Really?

    I had a beautiful "pro" drill and killed the batteries after a few recharges on msw. the cost of the drill batteries added to the price of the msw inverter and I could have bought a psw.
    Which, after realizing what I had done, I had to do anyway.
    PSW. I ain't going back to any horse and buggy.
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