No exaggeration, this video is life changing. As an audio engineer that spends all day every day thinking about audible hums, buzzing, and regulating the temperature of my equipment, this is a godsend. Thank you

Thank you for this demonstration; changed my mind about getting a pure sine wave inverter.

Great video. I ended up getting one of these pure sine wave inverters. Works great. Now my fan is not so loud. Thanks again.

Thanks for the info, I'm now planning on a pure sine wave inverter, no doubt about it.

Finally the difference between the two types of the waveforms produced by these two inverter categories is simply the lack of harmonics on the part of the pure sinus inverters. The modified sinus inverters have practically only that drawback. Nevertheless, if their design is smart, they can be used with any load. Smart design means the full elimination of the third harmonic, i.e 180Hz for 60Hz mains (or 150Hz for 50Hz mains respectively). Once this presupposition is established, there is no practical drawback of the modified sinus waveform against the pure sinusoidal one (unless if one wants to sell energy in the utility). On the other hand, the term "modified sinus" means exactly that fact. The full elimination of the third harmonic content from the output waveform. Thus the resultant waveform will be a decent replacement of the the sinusoidal one, being completely harmless for any load, no matter how delicate it might be. As for the electronic appliances of our days, all of them are using "switch mode power supplies", which really don't care about the input waveform, being capable to work even with pure D.C voltage i.e. directly from battery supply. All that's needed is the voltage level, which should be within the range the power supply can handle. Many of them are universal, that is, they can operate from 80 to 280 volt (with the mains frequency being unimportant any longer). In any case their operating voltage range, i.e. the important parameter, is written in their info label, on their body.

winston, have you measured if there's any difference in amperage drawn between the two inverters, on the same appliance & setting? especially for the inductive load...

really helpful man, anyone who is new to inverters would benefit alot from this

Pure sine wave inverters have LOWER conversion efficiency, because of transformer losses. You see higher power usage on modified sine wave because you power a simple electric motor with it. Its designed for a pure wave and wont work well on modified wave. You measure at the output of the inverter so you skip the inverter itself in the test. You measure efficiency of the motor on the current type provided not the inverter - this is still important, but it hides the whole picture. You should measure on the input to the inverter. With the increased efficiency of modified wave inverters, you might see the difference in power use of you motor will be much less. On the other hand modified wave is just as good as pure wave for powering switching power supplies. After all, internally they just make the wave strait then chop it up again, so it doesn't matter for them how choppy it comes in.

Should have watched your video before purchasing my inverter. Absolutely hate the whining sound every time I use my Modified Sine Wave unit. I paid $30.00 for an 800 Watt Black & Decker inverter, should have known it was too good to be true. Well, lesson learned. Almost hard wired my inverter to my vehicle before watching your video. Thanks.!

i was looking everywhere to see the diffrent between Sine wave or modified sine wave and this video helped me alot to understand thx alot

Very interesting. I'm glad that I didn't plug anything important into my "modified" inverter. I just ordered the "pure" on Amazon. Thanks for posting.

Maybe stupid question, but anyway: is it possible to convert square wave (PWM), to the true sine wave?

Does your fan hum on low when you plug in to the grid supply?

My set up uses a modified sin wave Krieger and I don't have issues with my light bulb or square box fans. Other fans are more sensitive. To those who want to set up an emergency box don't be afraid of using modified sine wave. I have been using them for 3 years now. I own 4 different types. My 8 watts led GE bulb don't care. My gig saw Dremmel coffee maker etc all run on modified sine wave.

Thanks for the simple explanation. ❤️

Thanks heaps for your video helped me out heaps in choosing between the two!

Unfortunately, the box showing modified vs. pure sine wave is INCORRECT. The left side (at around 0:15 seconds) depicts a step function....so that 12V is boosted to about 120 v for 1/120th of a second,then boosted to -120V for 1/120th of a second. That is a 'step function.' Modified sine wave inverters often use 3 steps...say it goes to 50V for 1/600th of a second, then 100V for 1/600th of a second, then 150V for 1/600th of a second, then back to 100V for 1/600th of a second, then back to 50V for 1/600th of a secon...and for the next 1/120th of a second - the voltage steps from -50V, -100V, -150V, -100V, -50V. The modified sine waves are obviously better than a step function, but not quite as good as a pure sine wave inverter. Pure sine wave inverters use Insulated Gate Bipolar Transistors (IGBT) to use Pulse Width Modulation (PWM) to create a pseudo-sine wave. It isn't real sine wave....but any circuit with inductance (like motors or transformers)...the effect is the same as a sine wave.

also, would it help clean up the power of a modified sine wave if I plugged in a Monster Cable power surge protector?

Thank you very much that was extremely interesting I did not know there was a difference. I'm definitely going with the good one.

Great demo, thanks!!!!

Actually, that's a square wave. A "modified" sine wave comes in a few styles and the worst is the kind that simply returns the voltage to zero for a short interval between the positive and negative peaks. The second best has two more steps in between. Check wikipedia and search for "Sine_wave_inverter". I made sure the picture of the wave shape is in there now (halfway down the page, two separate sections).

After having a 300 Watt Pure Sine Wave inverter for 4 years I went and picked up a 750 Watt modified wave inverter from Walmart. I wanted some kind of backup inverter for shtf and I was having too much fun using my old car batteries charged with solar to charge all my aa/aaa/lithium usb banks etc and did not want to risk the pure wave getting weathered or stolen. That said it performs well even on a laptop the only area it has a problems is my really nice Phillips PC speakers buzz on it.

Thanks for your explanation.

which type of inverter will be best for home used like tv fan bulb

Thanks for making this video. It would be interesting to see what the 12v input wattage is compared to the output that you have demonstrated.

Would you recommend pure sine wave inverter or modified inverter to power a speaker box? I'm trying to build a portable power source to power a TDK Wireless Sound Cube. It draws 18volts @ 2amps

smart move pure sine wave all the way!!!!

Thank you for this really useful information!! :) So a pure sine wave inverter smooths out the wave from + to - to +, etc... Is there any way you can also smooth out the motion of your camera ?? :) lol

Do you think a 300 Watt would work for converting a 110V lawn mower motor to 12V Battery?

It buzzes because the square waveform has an extremely fast rise time. For inductive loads (motors), the back current is related to the rise time. Sine waves are smooth; square waves are abrupt and fast. For capacitive loads (most things), a square wave is an immediate change in voltage, causing a huge surge current to charge the capacitor. Overall, the humming noise is due to extra magnetic fields brought on by the larger currents. This causes a 60Hz physical vibration, which you hear as a hum.

To power a portable Sony stereo, I was using a cheaper modified sine wave inverter, I accidentally reversed the + and - on my battery connection last evening and blew the 2 non replaceable fuses inside the inverter. After much research and talking to 3 different electronics technicians today, they all told me my Sony stereo will operate better and last longer with a better pure sine wave inverter. Ordered an Aims 180w pure sine wave inverter for $64 I'm now glad the cheaper $34 Cobra 400w modified sine wave inverter got blown out, my portable Sony stereo is the best sounding unit ever made, and they don't make them any longer, can never replace it, so happy I'm going to be treating it better from now on with pure sine wave power nearly, or identical to higher quality household A/C current. Modified sine wave is not good for electronics like TV, stereo, battery chargers etc. They may work, but not as well or last as long.

Good information. Thanks

Great video!! thanks for sharing.

Can i ask what the name of that plug-in watt/volt/kwh reader is called you used at the end? that would be most useful for my solar project..

Good review!

Thanks for sharing buddy

My Powerbright 1500 has been very reliable. Big plus is motor life & digital timers. Worth the extra money for sine.

+Where did you purchase the Pure Sine Wave Inverters?

From the scientific experiment perspective (control group/test group), I'm wondering about the accuracy of the experiment, considering that the Pure was 300W while the Modified was 1100W. Would the humming be a result of the type of sine wave (as you are suggesting) or possibly as a result of the increased Wattage allowance? I wish the 2 inverters in your experiment were equal in Wattage, as it would eliminate that variable from the results.

I need to charge a 12v 2000 mAh lead acid battery for my VHS camcorder in my car. Can I use a modified sine wave inverter?

Good info. Thanks.

Good vid. Thank you.

Hi friend. Please let me ask if i can work with modified sine wave inverter my ''motion sensor (PIR)'?????

If it Runs on DC you can use a modified a cheep one should work just fine. Over a long time it may kill the power brick but they are cheep. If you know what you are doing you can run it straight off the battery if it is running a 12 volt.

They failed with that picture of a modified sine wave. That, my friend, is a square wave. A modified sine wave looks like a sine wave but it steps up step by step instead of a smoothe waveform

I have a 1000 watt modified sine wave inverter. What could I use it for that wouldn't be harmful...?

i hear modifeid vawes is not good for charging lithium batteries is true ?

can i use a modified sine wave for audio equitment

Yes Pure uses more power on standby but some of the nicer ones have a sleep mode. my 300 watt uses 0.7 amps. Some of the modified us a lot of power also so you need to look before you buy.

nice info cheers

Yes i learned this the hard way with my solar projects... Driving motors like fridges or freezers get pure sine.

Those square wave units can be converted to sine wave with LC circuit that can plug into outlet then to the load. Its not complicated just need to design a box that plugs into the inverter outlet and with a coil and capacitor value you can effectively bypass the humming problem. The hard part is designing the LC circuit.

I'm sea sick. Get a tripod

thank you

I've been working off-grid for several years now, and have seen every type of electronic plugged into every type of power inverter or generator. Many sensitive electronics will opt not to recognize cheaply inverted electricity. Pure or true sine wave works every time, so spend the money if this is what you are powering.

gracias por compartir

nice job

will my modified sine wave inverter break my computer, tv, and fans? i've been really worried about using it

I use cheap $30 500w inverter to charge my laptop, bulp light, charge my phone & camera, desk fan, drill, etc. The device which is not supported is AC and Fridge. Hope this help...

Dirty power vs clean power, wouldn't a surge protector with built in filter take care of that too?

I know about the buzzing. When my UPS (for my computer) kicks in I can hear the buzzing in my LED lamp that is also connected. I guess the PC can handle the modified sinewave. But I am going to buy a 300w pure sine. And might buy a modified 1.5kw.

That's how its done in fact. Create a pure sine with a cristal/ LC circuit (unloaded), charge a capacitor until it reaches the at that point in time needed voltage level (compare it with the created sine). This a few 1000/sec (? don't know how much exactly). Filter out undesired noise with other LC circuit.

This is the kind of video I like to hummm to ;-)

I believe a pure sine wave inverter uses more battery current than a modified sine wave inverter. So if you aren't using sensitive equipment, a modified sine wave inverter will work just fine, and your battery power will last longer.

Im using Avasva instructions to make it and I do it already :)

This is a fantastic piece! I use this for my music gigs when I play on the go. It powers up my keyboard, 2 speakers and mixer together with mics etc. The connection is strong, it has never blown and extremely reliable for tight situations. Highly recommended. amzn.to/1p8v2AE

I don't have a In line watt meter or I would do that.

Thanks

That is true, modified sine wave as he show on the begining goes on-off, pure sine wave is always on, so make sence battery will last longer on modified sine wave.

Wondering about losses and efficiencies.... On the fence about spending an extra $100 ($80 vs $180) on my simple setup for pure sine vs modified sine wav . Also finding Inverters just don't last very long for me.. wish they were generally more robust. My battery Is my starter 70AH 120RC. I run power tools and appliances 500w to 1000w, but need to run a freezer for 8 hours while a 200w solar panel feeds my battery through a MPPT controller. Just had my 1200w modified sine inverter go bad after an accidental short.. they are so sensitive. Somebody wrote a review on my inverter saying the inverter was eating 200W to power a 100W in devices... I try not to use the inverter unless it absolutely needs a lot of power and 110v... for led lights and fans, why not stay with 5vdc and 12vdc?

No that will not do anything. their is something called a ac filter that can turn a modified into a pure but you cant find them anymore. They where for people that lived way out in the country that had signal degradation.

Those diagrams are interesting - I've never encountered a 'modified sine wave' inverter that produces a square wave, modified sine has a 0V gap between each peak. A square wave would actually be better for running some motors.

helpful

damp, yes it is a problem. It will corrode internally and fail fairly prematurely with humidity levels over 80%. Cold is not a problem for the inverter - just the batteries.

yeah commercial outlet power these days is pretty dirty, gotta get a pure sine power strip for it.

Good video, try a tripod for taking your video

are these safe to charge a laptop???

But if you place a capacitor at the output of the modified sinus wave inverter, then the hamming dissapears.

best

I noticed the humming on my 750 watt , looking to upgrade , also my tv screen went black due to the inverter lol

Should not be a problem

CLEANER POWER?!

so you shouldn't run a blow dryer with the put some wave, even if you had let's say a 3000w pure some way inverter.

Just because a motor is buzzing does not mean it's very inefficient and is getting hotter then on the pure sine wave. Single phase (as well as 3 phase) motors don't care a lot if what they get is square wave (or modified as it's called by sale people which is incorrect) or a sine wave. The humming is just annoying for people, not for motors.

Unless your metering equipment is specifically designed to measure that type of wave form it will not be accurate. No mod sine wave inverters produce a square wave like the picture on the box. It's a lot closer to a triangle wave with the sharp points rounded off. Motors that have brushes (power tools) work fine on mod sine inverters. Induction and shaded pole motors most (household appliances) do not. I use a 2000w one instead of hauling a generator around to run a skil saw and drill.

um, not trying to one up anyone, but a 'square wave' is like plugging in a pos and neg wire, and switching the polarity rapidly... appliances notoriously 'buck and fight' with square wave output. Actual SINE wave refers to the pattern shown on an oscilloscope, the second picture, which shows that the POLARITY REVERSALS are GRADUAL over a period of time, so small we hardly notice it (unless we have a finger in a light socket LOL) - the GRADUAL reversals of polarity are MUCH SMOOTHER than square wave. Think of running a baby carriage up and down a flight of stairs. OK, now carpet the stairs and SMOOTH the sharp edges and then the carriage will roll MUCH SMOOTHER up and down the same stairs. MODIFIED sine wave is NOT sine wave, it only shows how the SQUARE WAVE can be manipulated with circuitry to 'shave the hard corners' off of the square waves, and it helps, but most of these use mosfets to manipulate the current (on/off switching) and some MSW inverters will have warning labels telling you to NOT plug in 'inductive' loads... like florescent lamps (blew a 1500 watt MSW inverter by leaving ONE CFC 'light bulb' in the circuits! BAM, gone. Tried to use a Weller soldering gun with same, BAM, blew the MOSFETS right off the circuit board...) so read up all you can on anything you plan to live with for a while. The best inverters are heavy, because they have REAL TRANSFORMERS inside them, like Tripp, my current champions. With all respect to M. Vineyard, yes that is a STEP current, and it is called a square wave... the sine wave shows the polarity reversing at the top 'loop/peak' and then again at the bottom 'loop/valley' usually the test lead will show pos at the top and negative orientation at the bottom. With a full sine, the current is never ACTUALLY OFF, unlike the square wave/rapid on off polarity swapping scheme - so the surges and 'ringing' in the circuits are minimized and even eliminated. This surging and ringing is what destroys all those small capacitors on the motherboards - and or the mosfets.

led lights like DC power

I got a mad headache watching this. I can hold this doing reviews without saking this bad

That sensor can't actually measure power on modified sine wave

Take the ground plug out and the buzzing will stop

Let me suggest. How about you put some 50/60hz capacitor to modified sine wave inverter. :)

I just got a cobra 400w on amazon for 30bucks plus 35 shipping to Rio ! That's how I get for living too far from US

sounds the same to me

which is best for using a laptop

I would be more precise, but 500 characters is too little. Apologies to all the other engineers who hate this description.

IMO, no inverter can provide you with electrical power as clean as that from the utility company. Power from the company comes from rotation and magnets. Pure Sine Wave Inverter doesn't have that, hence the result.

Why don't you try closing the damn shades in the background and keep the camera still so we don't get dizzy

Modified Square wav

So right I killed my netbook psu with a modified sw inverter!

Hold the dam camera still will ya!? 😂😂