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

[Bill_Bright]

I consider many steps a sine-wave unit

Well, that is just wrong. Sorry, but you don't get to define your own terms. Science, the Laws of Physics, and the industry (though cooperative consensus) gets to do that. Marketing weenies try to define their own terms (like "wireless router" - a totally inaccurate term since all routers are wired) but they are simply wrong too.

A sinewave does not have steps.

 

[Shrek]

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.

Didn't realize there were no more modified square wave units

 

[newtekie1]

Didn't realize there were no more modified square wave units

I'm not saying there aren't any at all, but the major brands have all moved away from selling them. Mainly because modified sine wave circuits have gotten so cheap to manufacture.

 

[R-T-B]

Except that isn't what the industry or anyone else considers it.

Tripp Lites terms glossary definition is actually very close to his. I really doubt any of these "Sine Wave" UPS's are a true Sine Wave. Making a true sine wave digitally is not easy.

EDIT: I just now realized that Tripp Lites terms glossary has aparently been removed post the Eaton-Aquisition. But still, point stands. Science and marketing often differ in terminology.

 

[MentalAcetylide]

Wow, we really went off on a tangent(or cotangent). Reminds me of the time I asked an electrician to find me a "Cosine Wave" or "Cosecant Wave" UPS... He never came back.

 

[R-T-B]

Wow, we really went off on a tangent(or cotangent). Reminds me of the time I asked an electrician to find me a "Cosine Wave" or "Cosecant Wave" UPS... He never came back.

Kinda but also not really. The Sine Wave marketing and it's importance (or lack thereof) was a key question, right?

 

[ThrashZone]

Hi,
Yeah not sure what all this is about op already bought one
Only question is why buy only one at that low price

 

[Shrek]

Wow, we really went off on a tangent(or cotangent).

I for one, learned a thing or two.

 

[ThrashZone]

Didn't realize there were no more modified square wave units

Hi,
The shape is more why the thin vertical units take up a smaller foot print more than anything.
I have a older square unit to sometime wires out the top is not possible but vertical and wires out the back is.

 

[newtekie1]

I really doubt any of these "Sine Wave" UPS's are a true Sine Wave. Making a true sine wave digitally is not easy.

I've hooked a huge number of these up to a scope, they most definitely are true sine waves if they are advertised as such.* Hell, they'll often give a better looking wave than what's coming out of my outlets.

*Yes you might be able to zoom way into the wave and see the steps, but they are so minute that when you look at the wave as a whole it's a smooth wave. And those steps probably aren't any bigger than the noise you'd see on the AC coming directly from the wall.

 

[R-T-B]

Yes you might be able to zoom way into the wave and see the steps, but they are so minute that when you look at the wave as a whole it's a smooth wave.

We were going into technicality land (which coincidentally, I rent a condo in) with that comment, were we not? So that is exactly what I meant.

I stand by my overall assessment that for 99% of applications this is nothing more than a useless exercise in definitions. This just reinforces that.

And those steps probably aren't any bigger than the noise you'd see on the AC coming directly from the wall.

Honestly even with said "microsteps" it's probably cleaner to the device than most grid power.

 

[newtekie1]

Honestly even with said "microsteps" it's probably cleaner to the device than most grid power.

Yeah, I've seen some really unclean power coming out of the wall in my house.

 

[R-T-B]

Yeah, I've seen some really unclean power coming out of the wall in my house.

Same. And I'm just monitoring voltage variation... I'm sure my forest power is appalling if I look at a waveform.

 

[Space Lynx]

Same. And I'm just monitoring voltage variation... I'm sure my forest power is appalling if I look at a waveform.

what in the flying fuck is forest power?

 

[R-T-B]

what in the flying fuck is forest power?

I was told it's what happens when the trees powers combine like captain planet.

In truth, it's just above ground wiring in a forest that leads to really tempermental electricity.

 

[Shrek]

Although probably not of relevance to the OP

I once lived at a place in the USA with terrible electricity and had the heated blankets on a UPS; all was fine till I replaced the heated blanket controllers and the new ones refused to run on modified square wave and I had to start using sine-wave units.

Electricity is better where I am now and I just use surge protectors, but don't feel the need to replace them periodically if they have an inbuilt protection check.

There are claims that "Over 50% of equipment failure can be attributed to power surge/failure."
Do I Need a Surge Protector? - A1 Computer Repair

To avoid the need to keep paying for batteries, I converted one UPS to run a few minutes on super-capacitors

• Replacing a UPS Battery With Super-Capacitors : 5 Steps - Instructables

after having tried to extend the life of the batteries

• Desulfation in Lead-acid Batteries; a Novel (resistive) Approach : 3 Steps - Instructables

Now I think about perhaps using lithium batteries as they may last a decade or two; but the UPS needs to be derated if one is not using high power batteries.

 

[Space Lynx]

Although probably not of relevance to the OP

I once lived at a place in the USA with terrible electricity and had the heated blankets on a UPS; all was fine till I replaced the heated blanket controllers and the new ones refused to run on modified square wave and I had to start using sine wave units.

Electricity is better where I am now and I just use surge protectors, but don't feel the need to replace them periodically as they have an inbuilt protection check.

I currently have my electric blanket plugged into the wall directly, no issues all winter with it.

 

[caroline!]

Thanks, this thread made me put together a dirt cheap sim sinewave UPS with a somewhat working battery to see if a box fan can start while running off it. The results varied depending on how I set or modified the fan, it being a simple 12" box model rated at 50W and 230V (see: https://www.amazon.co.uk/COOLTONE-FA-B12-12-Inch-Box-Fan/dp/B07997BKW8 for an example)

All of the tests were made with the UPS running off battery power. Output voltage: 226V
Test 1: Plug in the fan and set it to position 1 (low) = audible hum, blades do not move, increasing the speed to pos 3 (high) makes them, noise continues for a few seconds and disappears.
Test 2: Set the fan to position 3 while unplugged, then plug it in = starts working just slower than if it was plugged to the wall, no hum at all.
Test 3: Repeat test 2 but turn off the fan and wait until the blades stop moving, then turn it on again = runs fine just with a little noise.

At this point I had cracked open the fan to find out what cap it had, it was 1.5uF.
Replaced with 2.5uF = blades try to move when the fan is set to pos 1 after being plugged in.
Replaced with 4uF=

The fan works fine with the 4uF cap on it.

After this I went and tried with the big fan I have on my room, since its switch forces the highest speed to be the first it'll always run fine no matter what, it also has a 4uF cap on it.
In conclusion: it depends on the fan.

As for the rest, if I were to measure my mains using a scope it'd display a rollercoaster rather than a somewhat proper sine-wave, it's not dirty or unclean power anymore, it's straight filthy and can easily be seen with a simple incandescent bulb, the constant fluctuations will make the bulb almost strobe, fortunately an useful invention like an UPS can take care of that, although I had resorted to something way more simple before having an UPS which was making my desk lamp use DC, I didn't even had a multimeter to properly measure mains voltage at that point yet that idea came to my mind and solved my problem, sure I could've used a CFL (there weren't any LEDs yet) but I had to make use of what I had at the time, and money wasn't between those things, at least not for something as trivial as a lightbulb, plus it was a nice way of learning how to use a soldering iron.

 

[Shrek]

This is fascinating for another reason.

I like to speed control my fans and at first tried triac control, but this resulted in humming on most (but not all) fans;
the reason I did this is to have a silent fan in the bedroom, so buzzing was a no go. I ended up using a variac which solved the problem, but a capacitor might be a cheaper solution.

But this is certainly off topic and so I don't follow up on this tangent.

Test 1: Plug in the fan and set it to position 1 (low) = audible hum, blades do not move

This confirms for me that an induction motor can't always start itself on a modified square wave.

 

[Bill_Bright]

it's not dirty or unclean power anymore, it's straight filthy

Did you by chance check your outlet (and service panel) ground to Earth ground? My mains waveform is not exactly picture perfect by any means, but I would not call it filthy. However, a bad Earth ground can certainly result in a very dirty waveform.

This confirms for me that an induction motor can't always start itself on a modified square wave.

Okay. But so?

I mean does that suggest a good stepped approximation UPS with AVR cannot support a computer? Nope. Or that it will not support the OP's setup? Nope.

Does it suggest everyone who has been using a good stepped approximation UPS on their systems successfully all these years all need to dump them and run out and buy new pure sinewave UPS? Nope.

And how often to you need to "start" a large motor during a power outage? And what is the current rating of this heating pump induction motor? Looking at some of the specs for some motors, I'm seeing many 1.3HP motors - with many considerably more demanding than that. That 1.3HP variable has specs of 230VAC 8.6A and 115VAC 15.6A. That equates to 1,483.5W and 1,345.5W respectively (assuming a PF of .75). You cannot get that kind of power support from any typical consumer UPS. Yes, I could have picked smaller motors, but I could have easily picked much larger (hungrier) too. Depend on the size of the home and furnace.

Frankly, if you want to support your furnace and have heat for your home during extended power outages, you should be looking into backup generators. Not an UPS.

I think it important to remind everyone again that the waveform output from an UPS - regardless if stepped approximation or pure sinewave - ONLY comes into play when there is a total power outage and the UPS is providing backup power. At ALL OTHER TIMES, the waveform being sent to the connected components is the exact same (or slightly regulated by the AVR feature) as the waveform coming out of the wall.

How often during the last 30 days did you lose power? How long was it out?

If you lose power for 1 hour in a month, that is still just 1 hour out of 720 hours, or .13% of the time. That is point one three. And frankly, 1 hour per month is definitely atypical.

Again, the purpose of a good UPS is to maintain power during a power outage long enough to finish typing your sentence, then "gracefully" save your file, exit your running programs, shutdown Windows, then power off your computer. That should take 5 - 10 minutes. Not an hour. The purpose of a UPS is NOT so you can keep playing your games for extended periods of time, or to start up heater motors.

Oh, one more thing. OF COURSE, it is important to buy a quality UPS with AVR. No one is suggesting buying a cheap, entry level UPS just as we should always buy quality power supplies for our computers. That SHOULD go without saying. With that in mind, just for an example, since EVGA and Seasonic supplies are often recommended,

Q: Do EVGA Power Supplies support UPS backup devices that support Line-Interactive AVR UPS which uses a simulated/artificial sine wave?
A: Yes, all EVGA power supplies support Active PFC and UPS backup devices.

Seasonic recommends pure sinewave UPS, but also clearly says,

a high quality simulated sinewave UPS from a reputable manufacturer could also be a possible solution to be used with our power supplies.

 

[caroline!]

This is fascinating for another reason.

I like to speed control my fans and at first tried triac control, but this resulted in humming on most (but not all) fans;
the reason I did this is to have a silent fan in the bedroom, so buzzing was a no go. I ended up using a variac which solved the problem, but a capacitor might be a cheaper solution.

But this is certainly off topic and so I don't follow up on this tangent.



This confirms for me that an induction motor can't always start itself on a modified square wave.

some motors are unable to start depending on certain factors, trying the same fan with its original 1.5 cap but on my UPS which is a pure sine-wave APC results in the fan being able to start even while set at the lowest speed. If we go to the experimenting side of things then a single test sample isn't enough to provide any coherent data to prove or disprove a statement.

The UPS I used was very similar to this: https://www.aliexpress.com/item/1005001422590664.html (China site)

Spoiler

It's the same 500VA model except the one I have is a different brand, it came with the same China outlets I couldn't use and had to replace with a wall socket hanging off the wiring, experimenting can be complicated sometimes.

Did you by chance check your outlet (and service panel) ground to Earth ground? My mains waveform is not exactly picture perfect by any means, but I would not call it filthy. However, a bad Earth ground can certainly result in a very dirty waveform.

Perks of living in a rural area I guess. There's no earthing, it's simply not a thing yet, it's an interesting tale imo, there's been an attempt to make it mandatory but failed, it involved phasing out the old type C sockets and plugs and replace them with type L which is literally the same just with 3 pins, some houses built between 2003-2008 do have them but when they realised people kept using C plugs and basically anything you want to purchase comes with a C plug it simply failed, oh and adding an extra contact to the existing socket models increased manufacturing costs by 20%. Wasted money and resources.

Oh, one more thing. OF COURSE, it is important to buy a quality UPS with AVR.

x2, proper AVR circuitry is important to filter out any anomalies but also increases the price of the unit.

 

[Bill_Bright]

Perks of living in a rural area I guess. There's no earthing

What? Of course you do.

If an older home, your wall outlets may not be grounded to Earth ground but surely your service panel is. And for sure, even if only two-wire outlets, they still need to be properly wired and in good repair. And no doubt, if you live in the US and in many other parts of the world, if you perform any upgrades or remodeling, you will have to install an Earth ground - assuming you want to pass code inspections.

That said, many UPS look for a ground, hot and neutral or else they indicate a fault and may not work properly.

 

[caroline!]

What? Of course you do.

If an older home, your wall outlets may not be grounded to Earth ground but surely your service panel is. And for sure, even if only two-wire outlets, they still need to be properly wired and in good repair. And no doubt, if you live in the US and in many other parts of the world, if you perform any upgrades or remodeling, you will have to install an Earth ground - assuming you want to pass code inspections.

That said, many UPS look for a ground, hot and neutral or else they indicate a fault and may not work properly.

Oh the panel is for sure. I did some remodelation, replaced most of the old wiring and fixed as much wrong splices and joints as I could find, rewired all the sockets and switches the same way and even cleaned their contacts, that fixed a problem with my computer shocking me every time I touched it, not sure what exactly was causing it as there were multiple things wrong but it went away when I rewired my room.
PSA as always, don't try this at home and call someone qualified to do any repairs.

(Un)fortunately there are no mandatory inspections, it's also probably one of the causes of the dozens of news about house fires caused "by space heaters" in winter that basically ignore the fact it's not the heaters causing the fires but too much DIY people and handymen using whatever cable is cheaper to upgrade and expand ancient installations, broken sockets, bypassing fuses to avoid buying new ones, using low end extensions, multiplugs and strips and a long list of other culprits. My own mom fell victim to a shady store selling heaters at affordable prices and that cursed thing ended up catching fire and burning the socket, it was simply a heating element and two wires, that's all, not even a switch on it.

My APC has been working fine despite it had a couple burnt resistors from whatever the previous owner did to it, bought it at scrap prices back in the day.

 

[Space Lynx]

does anyone know what ever happened to Andy S (I forget how to spell his last name in username)? he used to post in a lot of threads I made and seemed very knowledgeable about a lot of stuff... maybe he ignored me I don't know.

 

[Shrek]

Good riddance... he was such a know it all! I believe he got cursed and was turned into an Ogre!

Now me, on the other hand, have been busy making a big mess of your thread!