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I have a question about: CyberPower 1500VA / 900Watts True Sine Wave Uninterruptible Power Supply (UPS)

SmartPro 1500va UPS System, Tower, 10 Outlets | Tripp Lite
PWM sine wave

That's a pure sine wave and I was wondering about stepped; but I cannot thank you enough for taking the time to try.
PWM sine wave in tripp lite terminology is a modified sine wave. They call pure sine wave "Sine Wave" with no PWM. I own one of their pure sine waves as well... (SMC1500T)

 
Out of curiosity, I plugged a small fan into my APC BackUPS CS 350 (an older UPS that undoubtedly uses a simulated sine), unplugged the UPS from the wall, and turned the fan on.

While the motor did buzz quite a bit, the fan started up fine and got up to speed.

EDIT: Tried it again, the fan does slow down when on battery and it buzzes. It doesn't buzz when connected back to AC.

Greatly appreciated; I am thrilled that the motor is able to start itself even if it struggles after. This is the information I was after.

Thanks to all the people here who understood what I was getting at and helped me by trying it themselves.

Seems the OP may go with pure sine-wave, and there is still the issue of possible primary capacity over-voltage for APFC supplies.
 

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Really appreciated

I am thrilled that the motor is able to start itself.
The buzzing and slower rpm is what I noted as well. Pretty common I think.

Also note it's incredibly hard to get a true pure sine signal from a digital device. Most that advertise pure sine ability just have a very much increased number of "steps."
 
Really appreciated; I am thrilled that the motor is able to start itself even if it struggles after. This is the information I was after.

Thanks to all the people here who understood what I was getting at and helped me by trying it themselves.
My fans don't struggle to start when I run them off of my UPSes.

Maybe you should stick with cheapass Lasko box fans from the hardware store/Home Depot. Or the GermGuardina HEPA fan that also works.

As far as I can tell, my UPSes don't really care what's attached to them.
 
With the UPS disconnected? Plugged in doesn't count as that is the same as plugging the fan directly into the wall.

Once again, this is not for a fan but a heating system pump.
 
The only thing I've ever seen care about sine wave purity is sensitive audio equipment, and even then, it tends to be the poorly designed ones. I had a Chinesium headphone amp that would buzz.

I'm sure there are medical and maybe some type of specific motors, but I've never seen anything else.

With the UPS disconnected?
That's how I did it. There's also the "self-test" but I never trust that over just unplugging the thing.

Seems the OP may go with pure sine-wave, and there is still the issue of possible primary capacity over-voltage for APFC supplies.
That's the only serious worry I would have but a well contructed PSU in this day and age almost certainly can take it. It also only really applies in Euro-style (240V) zones.
 
Your help has been invaluable; the buzzing was inevitable, it was the starting I wondered about.

I am concerned that cvades did not first disconnect the UPS for the tests.

Once I plug a UPS into the wall socket, it stays there until I move it. That's pretty infrequent since I've been living in this small 650 sq. ft. 1BD condo for nearly 15 years. Most of the outlets where I'd plug in a UPS already have a UPS. I assure you that I plug and unplug various devices (including fans) into my various UPSes without unplugging them first.
 
Why would I disconnect the UPS first? NO.

I'm sorry to disappoint but I treat my UPSes like power strips until their batteries die.
 
To test the stepped output and not the mains sine-wave
 
Remember, I have used stepped output UPSes since the Nineties. I have never fussed over this.

And I don't live in the same place today that I lived in 1992. I've probably lived in five locations.
 
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I don't need to unplug the UPS to run a fan. That's your original scenario.

But I will bet you a buffalo nickel that I can unplug my UPS, plug it back in, plug in a fan, turn the fan on, and it will work.

After all, every single UPS in my home existed in a state where it never was powered by my house electricity. Every single electrical device that I have used had never been used in my house at one point.

And if the wall power fails, essentially that's like unplugging the UPS anyhow.
 
I originally asked not if a heating pump induction motor would run, but if it would start on a stepped wave-form.

Some people were most helpful by giving this a spin, and in the case of a fan it would indeed start; of course different single phase induction motors have different starting mechanisms (three phase induction motors don't need help to start).

Room fans use shaded poles, my pump uses a starting capacitor.

Start Mechanism in Single Phase Induction Motor – Simple Circuit Diagram
"The single-phase induction motor is not self-starting device."
 
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Look, OP's original post was never about induction motors. As I EXPLICITLY mentioned, I don't know what type of motor is in my cheapass box fan.

You demonstrated surprise that a fan plugged into a UPS actually worked.

No one here really gives a hoot about some bizarre, obscure electrical anomalous situation that you are imagining. The real world inquiry is whether or not a fan works with a vanilla UPS. It does.

But just for silly amusement, I will unplug my APC Back-UPS ES 550 unit from the wall for several minutes (just like the way it was shipped to me from Amazon.com's warehouse), plug it back in, and plug my cheapass box fan into it. JUST LIKE IT DID YEARS AGO.

And the fan will work.
 
A small 150 watt fan and a 2 h.p. tablesaw are not comparable. Your heating system does not need a UPS. It can go a few minutes to an hour without harm to you, your house, the pipes, or anything else, without power.
 
I want to keep it running to avoid the pipes from freezing.

Anyhow, it's been an interesting discussion; but for me the ability to use a UPS to prevent damage to pipes seemed a useful one.
 
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How many HP? Motor service factor? What happens if you can't get power to it after batteries die?
 
1/25th HP

Good point about the batteries; of course, if I was desperate, I'd use my car battery and run the car on and off to keep it charged.
 
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OK, so apparently you have diverted on a tangent targeting a highly specific system running a home climate system.

The OP was about running a gaming PC and videogame console after a power failure. Your usage case has NOTHING to do with this.

I hereby bow out of further discussion of this topic.

Best of luck.
 
OK, so apparently you have diverted on a tangent targeting a highly specific system running a home climate system.

The OP was about running a gaming PC and videogame console after a power failure. Your usage case has NOTHING to do with this.

Twice I attached the document
"PSU_and_UPS_Compatibility_Test_Report"
PSU_and_UPS_Compatibility_Test_Report.pdf (libero.it)
which I believe directly addressed the OPs primary concerns.

The point I was hoping to make with induction motors was that power supplies were not the only thing that reacted differently to stepped waves.
 
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Ummm, it appears CallandorWoT's thread (this thread) is on the verge of being hijacked.
everyone keeps saying the batteries are expensive, but in all honesty buying this every 2-3 years doesn't seem like a bad deal for $53...
It sure is a lot cheaper than buying a new UPS (or a new surge and spike protector - unless you get a cheap one) every few years. But still, it is like spending money on insurance. It is expensive, everyone hates it, you hope you never need it, but if you do need it, you are glad you have it.

if i buy the one in my topic title the cyberpower true sine wave, is that lithium or lead acid?
If it is Lithium Ion, it will clearly say so. That said, the battery chemistry has absolutely nothing to do with the output waveform the UPS creates.

As I mentioned earlier, my target is the heating system induction motor pump, so I could keep the pipes from freezing during an extended outage
You mentioned heating system but you NEVER said anything about "extended outages". UPS are NOT intended for extended outages. They are for short term outages only. If you are concerned about extended outages, you need to invest in a generator. There are whole house types that run on natural (or LP) gas and there are some that operate on diesel. These typically are wired into your service panel, and kick in automatically when needed.

And there are portable models that run on gasoline - which is what I have. These you have to drag out of storage, fill with fuel, power up, then connect your devices. Mine is a 5KW unit that will easily support my fridge, freeze, two windows ACs, TV and computers - and will do so for as long as I keep fuel in the tank.

BTW - if your whole town loses power, keep in mind your local gas stations may not have power either! :(

Anyway, the idea is for the UPS to carry you over until the generator goes on line.

I never know if my UPS is running on batteries or not.
Why not! Even my cheapest 75W USB charging UPS I got for free :D though a Newegg promotion emits irritating beeps when running on battery. My better UPS beep and, those connected via USB communications cable to my computers, send pop-up windows telling me I am on battery.

I always know if my UPS is running on batteries or not.

I assure you that I plug and unplug various devices (including fans) into my various UPSes without unplugging them first.
Ummm, I think you misunderstood his point. He was talking about testing the UPS by seeing if the UPS (while running on battery - thus unplugged from the wall) could start the fan spinning when you turn on the fan.
 
I consider many steps a sine-wave unit; it's the modified square wave that bothers me.

modified square.jpg


For me the following is sine-wave for most purposes, including an induction motor

True vs stepped sinewave.png
 
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Twice I attached the document
"PSU_and_UPS_Compatibility_Test_Report"
PSU_and_UPS_Compatibility_Test_Report.pdf (libero.it)
which I believe directly addressed the OPs primary concerns.

And without context that report seems to say PFC doesn't like simulated sine wave. Except we have direct statements from people that design power supplies for a living that APFC units are fine with simulated sine wave UPSes.

The issue with the report you posted is, as I said, no context. First, the "simulated sine wave" UPS they tested was not a simulated sine wave unit, it is very clearly a square wave unit, the cheapest of the cheap. You don't even see these anymore. Modern UPSes are stepped. Then you have to actually ask, well what is that report telling us. They are reading the bulk cap charge and saying that it goes higher than it should with a square wave unit. Yeah, because the square wave units have a spike when the voltage changes from 0 all the way up to +120v or down to -120v. The cap will charge to that higher voltage. This doesn't even have anything to do with APFC, a non-PFC will have this same problem. The bulk cap overcharge is going to happen no matter what.

But the stepped sine wave units that are on the market today don't suffer from those large spikes because the voltage changes are much smaller. Even just adding one step between 0 and 120v is enough to suppress the spike to acceptable levels.

I consider many steps a sine-wave unit; it's the modified square wave that bothers me.
Except that isn't what the industry or anyone else considers it. A stepped sine wave is a modified/simulated sine wave. Your report is on the insanely old square wave units that no major brand sells anymore. The test you posted is using units that are Modified Square Wave, not modified sine wave. Modern cheap units are using Stepped sine.

upswaveform.png
 
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