Do I need a special UPS for my two PFC PSUs?

rpeters83

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I'm completely new to UPSs. I have a Corsair TX650 in one machine and a Antec earthwatts 380w. Both are active PFC.

I've been looking at the CyberPower models, as they advertise pure sine voltage. Do I in fact need a special UPS like this (such ashttps://www.amazon.com/dp/B00429N192/ref=cm_sw_r_awd_AdXVub01SZKSR), or will one of the cheaper models suffice. Are there any from APC that I should consider? Thanks.
 
The sine-wave Cyperpowers are nice since you can turn off the display and alarm, but otherwise it doesn't really matter.

I've run various active PFC PSUs on the [strike=]non-sinewave[/s] [edit: actually it is the stepped sinewave version] versions for several years now with no issues and the power here is terrible. Probably 15-20 times a year the power drops and the UPS kicks over to battery.
 
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I don't think it matters for a decent PSU. Motors, however, don't like running off a square wave.
 
It actually does matter for decent PSUs, because decent PSUs have PFC circuits, and can detect square wave as dirty power and put the PSU into protection.

Traditionally Cyberpowers are modified Triangle wave, not true sine wave. Works better then Smoothed Square, but still not quite right. So hopefully this new model is actually true sine. That would be awesome.
 
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Thanks. Off topic, but if I buy one of these cyberpower models, am I able to eventually upgrade the battery to one with a higher charge, or am I stuck with the same replacement battery?
 
Off topic, but if I buy one of these cyberpower models, am I able to eventually upgrade the battery to one with a higher charge, or am I stuck with the same replacement battery?

For that I would get a refurbished server grade UPS like an APC SmartUPS 1500. These sell for less than $200 US with new batteries on eBay.
 
Thanks. Off topic, but if I buy one of these cyberpower models, am I able to eventually upgrade the battery to one with a higher charge, or am I stuck with the same replacement battery?

Given that higher capacity batteries are physically larger you can answer that yourself.
(hint: the answer is no, as they won't fit)

If you want expandability I'd second the SmartUPS recommendation as they're generally expandable. Though I would recommend against flea-bay, look at someplace like RefurbUPS or some other reputable source.
 
You can add a larger battery to even a cheap UPS by extending the cables and storing it outside the UPS. I recommend using cables 10 gauge or thicker (maybe 8 gauge) - a cheaper UPS is probably going to use 12-14 gauge internally. For the battery, you want a sealed AGM battery only, unless you have good ventilation, which is unlikely for home use. You'll also want a high-quality battery like Deka Intimidator and/or a marine battery. Marine batteries are absolutely necessary with cheaper brands like Autozone's Duralast - the regular car versions would fail in just a few discharges (though if you shut your equipment down before the battery gets under ~25% or so, it would be fine). With the higher quality batteries like Deka Intimidator, the marine versions are still recommended, but not as important as with cheaper ones.

I would recommend a higher-end UPS as previously mentioned. I'd take APC SmartUPS over any low-end consumer model, but I recommend Emerson/Liebert and Eaton/Powerware over APC if you can find them for a decent price. They are not as common as APC on Ebay but they are still generally available there for prices comparable to APC.

If you do get an enterprise unit that does happen to be expandable, you would have 3 choices:
1) Buy the "official" battery expansion unit to your UPS - sometimes they can also be had for cheap on Ebay, but supply of these is lower and sometimes they are not available for cheap and may cost around $300-500
2) Buy a connector, such as Anderson PowerPole or whatever, that connects to the expansion battery pack connector, and use it to make your own battery pack. Note that different UPS use different connectors. Some use easy-to-find connectors and some use much more proprietary connectors nearly impossible to find.
3) Extend the wires from the main battery area in the UPS just like you would with the cheap UPS

Any of those solutions are fine when done right. If you build your own battery pack or extend the wires, you obviously want to make sure that it is secure and safe from shorting out.

If you use a relatively powerful UPS, say 1000VA or higher, and you use option 3 to extend the wires out of the unit, I would use a minimum of 8 gauge rather than the 10 gauge I recommended for the cheap unit. Heck, maybe a good gauge is to just use wires a step thicker than the stock ones, i.e. use 10 gauge if the unit uses 12 internally, 8 gauge if the unit uses 10 internally, etc.

And finally, the cheaper the UPS, the longer it will take to charge a larger battery. A car battery with a cheap consumer UPS could take a day or maybe even two to charge. It's still useful if your power comes back on for 2 hours and then goes back off again because it'll still get a partial charge. This is more a comparison between cheaper UPS with small chargers and better UPS with beefier chargers rather than a recommendation against large batteries. Even with the long charging times, it's still better than tiny batteries.
 
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Im currently using the cyberpower 1500FPCLCD with an Antec 1200 and 2x 780gtx classified. No issues even under full load after pulling the power plug. No whine or hissing sounds from ups or power supply.
 
I run two of the Tripp Lite OmniSmart OMNI1500LCDT. It does a "PWM sine wave output" when it's on battery.

My stuff has Active PFC and doesn't seem to mind.
 
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