UPS with the best (purest) sine wave output

[needathing]

I need a UPS with pure sine wave output. When the specification says "pure sine wave" or "sine wave" (I've noticed e.g. APC uses word "pure" nowhere), does it mean the output is pure sine wave comparable with the utility power?

Or is the "pure sine wave" only a better approximation of a stepped sine wave? In that case what is the cheapest UPS with the best sine wave available?

thanx

 

[TeraMedia]

What are you trying to do? Is this for Hi-fi A/V? Medical equipment?

I presume you already know that utility power is anything but a pure sine wave...

 

[GUESTPROUSER]

I work with ups's daily

Here you can see that there 'Pure' sine wave ups's aren't called it pure \/
http://www.apcc.com/resource/include/techspec_index.cfm?base_sku=SUA1500 - I love these, banks use them all around the world
http://www.apc.com/resource/include/techspec_index.cfm?base_sku=SUA1000RM2U


Here you can clearly see that this isn't pure, it's Stepped approximation to a sinewave \/
http://www.apc.com/resource/include/techspec_index.cfm?base_sku=BE550R
http://www.apc.com/resource/include/techspec_index.cfm?base_sku=BK350

Matter of fact, they don't even state 'pure' on their $10-20k ups's. If you have a problem with their style of naming, you can email them a complaint. Pure isn't a word manufactures have to use, some use it, some don't. In reality, there's no such thing as a trully pure sine wave ups. Find your nearest Electrical Engineering company or school and they'll be glad to explain this to you.
http://www.apc.com/resource/include/techspec_index.cfm?base_sku=SUVTP10KF1B2&total_watts=4000
http://www.apc.com/resource/include/techspec_index.cfm?base_sku=ISVT10KF1B2S&total_watts=2000

You don't necessarily need the best sine wave for general home pc's.

http://www.amazon.com/APC-SUA1500-1500VA-Servers-Networks/dp/B00006BBK8
Get this one and be done with it.

'Pure' sine wave, almost 40 amps (this means "at-least" 1.5 hours of power for one pc), 950+ watts and easy maintenance.




Email APC for any further questions you have, your the costumer and it's your money.
GPU.

 

[needathing]

What are you trying to do? Is this for Hi-fi A/V? Medical equipment?

I need to back-up every kind of equipment. Wattage is not an issue but what I need is a prolonged running time on battery. And I have bad experience with stepped sine wave UPS. The PSU of my computer started buzzing every time it was on battery in such a way I was feeling it's going to explode. It was like very high voltage wires.

As I found the PSU manufacturer doesnt recommend using stepped sine wave but I had the same problem with monitor and other equipments (albeit they weren't buzzing that loud). So it's more UPS than PSU issue.

I presume you already know that utility power is anything but a pure sine wave...

What?

No, I don't know that. As far as I remember physics the power is generated by a magnetic rotor inside a magnetic stator (sorry for bad translation) - what should generate pure sine wave.

 

[needathing]

In reality, there's no such thing as a trully pure sine wave ups.

what? can you elaborate or post a link to some articles that address this issue? Does it mean that every UPS I eventually buy will stress the connected equipments when running on battery?

You don't necessarily need the best sine wave for general home pc's.

I do. As I just wrote one post above I need prolonged time running on battery without overly stressing the connected equipments...

Email APC for any further questions you have, your the costumer and it's your money.
GPU.

I did (actually the same time as I was setting up this thread). But I need some independent opinions because the sellers will never tell you everything (even if they are ultra-fair to their customers they still have an insider view which causes distorted perception).

That's why I need some independent opinions and I thank to everyone who gives me some!

 

[shiekh]

I took a look at the output of my APC sine-wave UPS and it is noticeably cleaner than the mains itself; so purity may no longer be an issue (The various local loads distort the mains).

 

[RetiredChief]

Desertengeneer. Minor Disagreement, As a shi%$^ input to a xformer can cause it to "Sing", overheat, or burn a winding open.

Nonsineasodiol waveforms poise a big problem for transform input. Example (Extreme case) if you applied a 120 VAC sinewave to a 10 to 1 stepdown xformer, you get a nice 12 VAC output. If you were to apply a 120 VAC squarewave you would get a positive spike with a short decay to zero then a neg spike decaying to zero (Delay will look like a RC curve. The output of the transformer is zero during the plateaus (Eout is dependent on rate of change – there is no rate of change for a square wave except durning the leading and lagging edges. This leads to rapid distruction of the Xformer as Current is only limited by the DC resistance of the winding, Very high, as opposed to the higher X sub L reactance. UPS typically have a very poor output waveform with the cheaper ones having a sharp leading edge..

As you pointed out the output is typically a pulse modulation of sinewave controlling the on time. It is the transition from on to off that creates the problem (as you pointed out). Also as you pointed out this sharp transition (Composed of very High freq) is what causes the eeeeeeeeee sound.

I would ask the manf to provide a waveform of the output under MAX recommended loads.

Cost, size, and Weight (emphasis on COST) are the determining factors. A true Sinewave cannot be produced by a switcher PS unless that output is rectified and used as the DC to a RCL, or Xstal controlled oscillator and applied transistor amplifier. For High current this is rather large and costly (also low effiency).

Might be cheaper to buy a generator.

 

[woohhaa]

You guys are way over my head but I am in need of a pure sine wave UPS. Apparantly some of the HP/Compaq desktop line is now requiring pure sine wave and it only took me 3 different APC UPS to figure this out.

I replaced the battery in an old Back-UPS 800 RS, that didn't work. I ordered a Back UPS 900 RS because I thought the old 800 was just bad, that didn't work. So I ordered a Back-UPS 1200 RS (same thing we use on our engineering work stations), to my dismay, that also did not work. I called HP and after a good bit or research the call center guy found this article.

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=c01718939&jumpid=reg_R1002_USEN

Do you guys have any pure sine wave model APC that would be ideal for keeping a desktop PC up though very brief power interuptions?

 

[thomasp94]

I'm having this problem with several HP dc7900 SFF computers. They are currently using CyberPower CP600LCD (340w 600va) battery backups but apparently these don't have the "true sine wave" because the power went out today and they all shut down immediately. Does anyone know if there a UPS around the $100 price range that has this feature? I have been looking through APC's website, but I have not found anything yet.

 

[yousaf2k]

buy a netcaa ups its pure sine wave and working 100%. i have 1200VA and its very good with lcd screen for load and voltage, battery status display etc.

 

[resonantwa]

Let me start by saying first, I am a "purist" and enthusiast and snob who is a little paranoid about things like knock-off jeans and "unclean" power sources.

So you could say that I too like the idea of "pure" power. But this is crazy talk. Unless you are trying to protect sensitive hardware (medical & audio recording / production), you have somehow snagged yourself on the necessity to have a Pure Sine Wave UPS.

No system manufacturer is going to require or recommend that you feed their third-world-assembled, mass-market circuitry with enterprise-grade power. A Pure Sine-Wave UPS would cost you at least 25% of the cost of even the most high-end desktop system.

If you're using enterprise grade components in your desktop system, then maybe you could rationalize protecting your investment with a $500-$600 UPS. But even mission-critical equipment like banking and data servers don't need Pure Sine Wave; they just demand highly stable and consistent power.

Yes, pure-sine wave power inverters and UPSes are indeed 'better' by virtue of the task they perform, but most likely you talked to someone who was also an enthusiast purist nut job who himself placed value on the simple 'better' aspect without context, and it fueled your own paranoia.

Really, a line-interactive UPS with AVR will do. Just get one with sufficient output to cover all the devices you want to operate "uninterrupted." And if you still disagree, I'd love to see a link to those specifications.

 

[Onus]

My Antec SG-650 will not run on the approximation of a unit like an APC BE750; it shuts off immediately. I got a SUA-750 though, and that works perfectly, and wasn't too expensive.

 

[resonantwa]

My Antec SG-650 will not run on the approximation of a unit like an APC BE750; it shuts off immediately. I got a SUA-750 though, and that works perfectly, and wasn't too expensive.

Ah dude, then you either got a bum SG-650, a bum APC BE750, or have bought a sham product. When you called Antec to tell them your PSU wouldn't power up reliably, they fooled you into not returning the unit. If you never called, your fault. Congratulations, you now have a $300 UPS to go with your $170 PSU.

FYI, if you read Antec's site, nowhere in the product manual or specifications does it indicate the requirement for pure sine-wave power sources. In fact, if you read the section about its PFC feature, you'll find direct references to the SG 650 technology meant to counteract issues with direct-to-wall power problems.

 

[randomizer]

This thread has been disturbed in its grave too many times.