CyberPower CP850PFCLCD UPS 850VA 510W PFC Compatible Pure Sine Wave

I bought the 1000VA model in this PFC series about a month ago to replace a fading APC Back-UPS ES 725. So far, performance has been encouraging.

My first impression upon opening the cleverly double-boxed packaging was that the picture size was deceiving. This CyberPower looks large. It's not. It's dwarfed by my standard mid-ATX towers. Eyeballed relative to one, it's about half the width, half the height, and two-thirds the depth. Positively petite for a tower UPS and roughly the size of the APC it replaced were that one upturned. Extras include a short coaxial cable and an RJ-11 phone wire. Build quality seems quite good, and the appearance in person is an attractive combination of gloss and matte black. Once booted, the UPS is completely silent with mains power. It buzzes quietly when on battery. There is no internal fan.

That said, let's drill down the major features of the PFC series:

Line-interactive - In the consumer world, there are three major types of UPS units: standby, line-interactive, and double conversion ("online"). Standby runs wall power straight to the device with minimal filtering unless it detects a major voltage change. Then it switches to battery. Line-interactive is the same, except with a filtering transformer between the wall and the device to handle most voltage variations. In an area with dirty power, line-interactive units won't cycle to battery power as often. With clean power, there's no practical difference between the two. Double-conversion means the battery powers the device and wall power only charges the battery. The isolation is helpful for sensitive things, but less efficient because the wall power is perpetually converted from AC to DC and back to AC. The heavy-duty inverter this type requires also tends to increase cost and noise.

Some areas will have greater voltage fluctuation than others. If you're in California and surrounded by industrial machinery, line-interactive or double-conversion is where you want to be.

Sine wave - When a UPS with this feature is on battery power, the cycling frequency of the AC it produces will be a pure sine wave instead of a blocky approximation. Most devices don't care. Some devices with a direct current path may care, as will electric motors and instruments that derive their timing from the power frequency. The majority of computers will work fine with any UPS, but certain power supplies with active power factor correction can have issues with the approximated sine output of lesser UPS units. If you buy a UPS without sine output, you'll find out immediately if there's a compatibility problem because the system will shut off when the UPS switches to battery. If the system continues to run, and it probably will if it's older or inexpensive, you're in the clear. Pure sine output is compatible with all computers and skirts the issue entirely.

This UPS has a capacity of 600W and 1000VA. You can ignore the second number if your hardware is recent or expensive. In the grand old days when the real power use of a computer (W) was 40% less than the apparent load to the power grid (VA), it made sense to specify more VA capacity than W. Now, though, with power factor correction (an attempt make the ratio of W:VA closer to 1:1) standard for years, the actual load is likely to be 90% or more of the apparent load. A 200W computer will probably use 200-225VA of capacity. You're therefore likely to reach the watt limit well before the one for VA.

Here's how the PFC models compare in maximum capacity, battery size, and runtime:

CP850: 510W max, 1 x 7 amp-hours = 7AH, 8 min @ 255W, 2 min @ 510W
CP1000: 600W max, 1 x 9 amp-hours = 9AH, 9 min @ 300W, 3 min @ 600W
CP1350: 810W max, 2 x 7 amp-hours = 14AH, 9 min @ 405W, 3 min @ 810W
CP1500: 900W max, 2 x 8.5 amp-hours = 17AH, 11 min @ 450W, 2 min @ 900W

While the latter two have USB charging ports and are physical larger to accommodate two batteries, all four otherwise share the same feature set.

Runtime doesn't scale linearly with load. A CP1500 feeding 100W may well last 60 minutes. At 900W, it'll last 2 minutes. That's a factor of 30 difference in runtime for only 9 times more load. To ensure your system stays on long enough to shut down properly, the expected draw shouldn't be more than about 70% of the maximum capacity. CyberPower's software can be configured to automatically shut down any single system via USB or serial, though the comments attached to this review note that older versions may write excessively to SSDs.

In my case, I've got a 12-drive file server, tower PC, router, switch, 24" LCD, and 32" LCD plugged in. The front-panel UPS LCD tells me that is an idle load of about 340W and 350VA. Projected runtime on my CP1000 is 6 minutes. A typical single computer and LCD monitor will draw 125W together. Gaming systems and larger screens, perhaps 150W-250W at idle. Most people with one system will find the CP850 adequate if they shut down soon after saving open work. Multiple systems or attempting to ride out a power loss would benefit from the CP1350 or above.

So how does the CP1000 perform? It's hard to say. It feels satisfyingly heavy even without the battery, but as I haven't torn it apart, it could well be filled with peanut brittle. There haven't been any lightning strikes, so the 1,030 joule surge rating (three times APC's typical rating) remains untested. Actually, the only stressor has been my laser printer. It's plugged into the same wall socket and when it heats up, the lights flicker and the UPS trips.

The switchover time from mains to battery isn't quite as fast with this Cyberpower. I know that because my APC caused a slight flicker on my LCD TV. This one gives a severe flicker that all but turns the TV off, though the other screen and the rest of the computer equipment are unaffected. It's also intolerant of overloads. Because a laser printer can easily pull 1200W or more, you're not supposed to plug one into any UPS outlet, battery-backed or not. I did by accident when I was moving cables around. The resulting shutdown and angry beeping was unsurprising. No docked stars for any of this, though I might have if the TV had actually turned off.

One niggle of note: my UPS took an usually long time to get past the initial startup. I spent about ten minutes pressing and holding buttons in accordance with the manual before it finally turned on. Since then, no similar issues, and I was alerted in a comment that it's possible to force the display to stay on by pressing and holding the display button until you hear a single beep.

All considered, I'd give this CyberPower a preliminary five stars. The APC lasted four years on the battery and five until the USB monitoring port went out, so that's the benchmark I hope it'll beat.

UPDATE 5/12:

I recently had an extended power outage. The estimated runtime was nine minutes at the start, but the UPS shut off in four or less even with a smaller load than above. This is significantly below Cyberpower's projections for this unit, so I'm docking a star. I would be tempted to choose a CP1500 if I were buying again. They come on sale for $150 or so every few months.

UPDATE 9/12:

I've had a new issue where the UPS stops powering all outlets for a few seconds at a time. No beeping or error messages ensue, but naturally, all devices turn off. The warranty for this unit is 3 years. Support has advised me to RMA. I'll update when that process is complete. Shipping to CyberPower was $18 through UPS. It's a very heavy package because they advise leaving the battery in.

UPDATE 10/12:

CyberPower has shipped me what appears to be a new unit. Turnaround time was a little over a week. No UPS signature was required. I didn't have any trouble turning this one on.

UPDATE 2/13:

No new issues to report. The replacement runs exactly as the original once did.

If you intend to downvote, please leave a comment. I do try to be accurate, I'd much prefer to know the issue.

Purchased this to replace an older UPS that wasn't compatible with my new Computer Workstation. I'm a Software Engineer and DataCenter SysAdmin by trade.

This unit works great at a fraction of the price of a "True SineWave" UPS I'd use in Server Rooms, and is suitable for workstations equipped with newer / high-end PFC (Power Factor Correction) Power Supplies.

I love the Onboard LCD, which shows a battery meter and a load meter; along with stats like Output Watts -- much like a kill-a-watt would show. You can decide whether to turn off the LCD on idle, or have it always on. I also love the fact that the Alarm can be silenced -- which is a huge blessing if you already know your power lines aren't stable, or if you have a need to intentionally run equipment on battery power for extended periods.

There's a USB and Serial port for monitoring, which (combined with software) can have your Workstation or Server gracefully shut down before all the power is drained. Though, with the LCD-based stats, you can still get all the info you need without a PC hooked up.

The USB Charging Ports in front have enough juice (Amps) for an iPad to charge.

The replacement battery cells are pretty common (go to a shop specializing in UPS Batteries), but "some assembly" is required to connect them to a "Harness/Wedge" between the cells. This is a common design for dual-cell UPSes, so your UPS battery shop may even have pre-assembled units ready for sale.

In sum: I got one for my workstation, and plan to get another for my entertainment room. At this price and the feature-set offered, this is a great buy. Well done, CyberPower.

First of all I purchased this UPS a little in the dark because I just could not find any reviews on it at the time; I guess it was a new model. I am glad I did, it exceeds my expectations... why?

1.It is silent! At last, my old 1500VA UPS was not loud but the drone was always there, this little guy, not a peep, you can even silence all the alarms.

2. Great load, I have 3x 27" monitors and my all computer guff hocked up for a total of about 580 watts full load and the UPS is just fine with that (70% load), even showing 10+ minutes of run time if power goes out.

3.It really looks cool, if these types of things can be considered cool, my old UPS was an ugly box with some LEDs on the outside, this little unit has a dark with white LCD screen (which was why I got this model over the older one) you can set it to read out whatever you like(Run time, load, VA, %, Watts, input, batt, output etc) and you have it on always or go off after a minute or so.

4.Software, not that I will ever really use it I guess but nice to know it works first time (on Windows 7 64bit at least) have not tried it on my Mac yet.

Over all I am very happy and cannot find anything about this product I am unhappy about, if I do I will amend my review.