Ever done UPS (uninterrupted power supply) comparisons?

My computer UPS has died. The big players I see at the local shops are APC, Tripp-lite and some Cyper powers. I would say the APC's look the most rugged but that doesn't necessarily transpire into better operation. Anybody ever researched them? Are some better then others at maintaining regulation? Do some put out a cleaner signal or is that important? I also would bet that much like flashlight manufacturers exaggerate about light output, I but some UPS manufacturers exaggerate about operation time when power goes out.

Have you checked the battery in your UPS? SLAs have finite lifespans, working or not.

You'll be hard-pressed to find any sort of hard data from the UPS manufacturers about runtime curves, efficiency vs load, etc. The watt figures they spec in VA (volts X amps) are almost never the actual AC load they will provide.

In general, inexpensive UPSs are inefficient and incapable of powering a signifigant load for very long due to inferior components and inadequate (or nonexistent) cooling.

You'll typically find better information on the more expensive UPSs aimed at professional workstations and servers. The folks that buy those need dependable performance specs since outages can cost them large sums of money.

I personally recommend the APC Smart-UPS 1400. I understand that the electronics inside are quite rugged and built for extended runtime. You can find them used at bargain prices. If you buy one used that doesn't work, just replace the SLAs (2x 17AH) and odds are it will fire right up.

As for brand names, I have good personal experience with APC and have heard good things about Tripp-Lite and Belkin.

I have a CyberPower CPS1500AVR protecting my system (file server with three terabytes, two LCD monitors, fax, printer, scanner, several routers, and a couple of powered USB hubs, including a land phone line) for over four years now without any problems. I even brewed a pot of coffee a couple of time during extended blackouts.

During electrical storms (and we get many - not far from the lightning capital of the world) not even a flicker to my system. Voltage regulation is top-notch and batteries are the originals. Power Panel Plus software is also very informative/functional and can be loaded as an option although not required for the UPS to function properly.

Quality voltage regulation is the most important spec when choosing a UPS (in my opinion).

woah i have no need for a ups here. there is rarely any blackout. i think it only happens every 40 years here

i get the old apc units and connect large wheelchair or truck batteries outside.
even the small system i have on my test bench will go several hours.its a 500va with a type 22 50 ah wheelchair battery.
yesterday i did a runtime test with a p4 1.8 15"crt
i had it running knoppix with every game running demo,open office,playing a mp3,and a 50w inverter plugged into a socket on the front of the ups running a shoplight.got 2.5 hours.the battery is a 3 year old pull from a wheelchair.

I'm a APC follower. They are rugged, solid, and "just work". Not a whole lot to worry about on them. If a batt. or board goes out just get another and swap it out. Plus if you want features, you can download apcupsd and do all sorts of control conditions on your PC or server. Even if you go with a high end model (Symetra or above) the apcupsd will still work.

Just my .02 cents worth.

Sincerely,

Shaman

if these "UPS" units do nothing but supply AC from a battery when the mains go out then why not just get yourself a nce inverter/charger from a solar supply company, and hook it up to one or two deep cycle batteries? The batteries can be much bigger than what comes in the UPS box, (and easier to swap out) and you can probably get a bigger better inverter/charger than what comes in the UPS box too, in case you need the extra AC..

many inverter/chargers have very fast transfer rates, (ie. Trace, and Xantrex) so AC operation isn't interupted.

check out these "home back up power" units;

http://store.altenergystore.com/Backup-Power/c523/

http://store.altenergystore.com/Backup-Power/c523/sort/2a/filter/82/

I am also an APC follower, but...

The frustrating thing about choosing the UPS is that the most common rating scale you see is only 1/2 of what you need to know.

They're addressing the characteristic battery issue -- the larger the demand for current, the lower the total energy you can suck out of the battery, so they give you the current load that the battery can handle at its given voltage (120 for us yanks), usually in kVA, which is kinda like Watts but not really even though you learned P=VI in electronics.

Then the other 1/2 you need to know is HOW MUCH ENERGY STORAGE is there??? They sorta give it to you by way of a few points of the energy curve, meaning they say "10 minutes at 1/2 load". Well okay that is informative, and technically accurate, but only in comparison with another similar kVA rated device of course.

Belkin, to their credit, is clear about both the kVA rating as well as the Joules, which presumably is Joule delivery for very lowest load and you can guess the rest of the curve. At least that's based on the units' boxes I've looked at.

APC also makes it very unclear about why you should pay an extra 1/3 or more for the "Smart-UPS" model instead of the "Back-UPS" model. And they keep trickling features into the relatively new "Back-UPS Pro" line that used to be "Smart" only, so it's really super hard now. The product differentiation is a total mess, at least from my perspective, but the products themselves do everything in their specs perfectly well. Just mind those specs, use the APC website, and never ever buy thinking "oh, this one should be the nearly the same as that because they're nearly the same name" no way.

Yes, power (Volt Amperes) and energy (Watt Hours) tell you much of what you need to know. Unfortunately I have never found the latter ratings on the models I have looked at. But there is one more thing I found quite important that nobody above has mentioned.

The better UPS models monitor the line voltage for problems in a more spohisticated way than the cheaper units. When they encounter a problem, they switch to battery faster and with less bad effect on the computer. I recommend that you get a "line interactive" model (see below for "types of UPS"). I had a lesser model once and it was unable to detect when a sub-second duration hit came back -- so it would leave the unit in battery mode and then simply run it down! The better consumer models retail for about $150.

The APC website explains the different types of UPS in a White Paper but you will have to register your name to read it.

If you do buy one, I hope you will insist an a "line interactive" model. The retailer will have to do some research to be sure that's what he's selling you. I think that all the APC models marked "AVR - Automatic Voltage Regulation" are line-interactive.

W.

Vmirag (and other's thanks for replying). I'm wondering if I'm better off just replacing the battery. I have a Tripp-lite Omnismart 675. I assume it's an interactive type you talk about because several times during near brown out conditions, typically in a hot summer day, I'll hear it click in and out within a very short period of time. I assume it's just a dead/weak battery. A few weeks ago, the power went out right while I was sitting at my pc. The pc and devices plugged into the UPS immediately shot off as well. But last night, I deliberately pulled the plug from the wall and the UPS worked fine. So I am not sure what is wrong. This UPS claims 675 VA and 425 total watts. For the battery backup outlets, I have my PC, 19" CRT monitor, modem and router plugged in. I'm assuming this is not too much for the UPS although I do have three hard drives running off the pc.

Also I was looking at Costco today and they had a Tripp-lite something or other that had a claimed VA of 1000 along with a digital voltage display which looked kind of neat but the total package size was much smaller then my current Omnismart 675.

I'm just starting using a UPS since I got a free, used APC Backups600. The batteries had split and died - APC says they only last 3-5 years anyway. I had to buy 2 new batteries for it (6v 12Ah sealed lead acid in series) from Battery Station, and it seems to work fine. I do notice that when I plugged a 60W light bulb into it, the lamp would blink once on changeover when I pulled the UPS AC plug, the lamp would dim a bit when running on backup, and the measured AC voltage would drop from our normal 120 to 115 (Fluke 8060A true RMS). Probably 'cause the waveform is only partially shaped, not a nice sinewave like the power company.

If you expect to get any runtime on battery backup, you need a big battery. APC thoughtfully gave runtimes in the manual, and 150vA (mebbe 120W) will run 53 minutes on good batts. I run a laptop, but a good desktop computer and CRT monitor alone will probably run 400W. I'm only trying my DSL modem and WiFI router on the UPS. I figure if a power outage occurs, I *might* be able to keep running for a couple hours IF my phone company has power to the DSL!

Also, I just bought a new, cheap 250 vA APC at work for a campus clock system that was getting confused during power spokes. I was only going to run the sound generator unit (rated 50W), but thought I'd try adding the dedicated little computer controller. Well, no go, it seemed to draw too much and the UPS immediately shut off and bleeped. That, and the teeny battery makes me think these things are generally seriously over rated.

New ones are usually not as good. High VA rating, small battery. I have a 450VA APC BackUPS made back in 1994, but its got a 12V 12Ah battery in it and weighs around 30 lbs. It runs my desktop PC + LCD monitor for close to an hour.

So the rule of thumb is, heavier the better, because the runtime is basically in the battery. The lighter, smaller, high VA rated units get around 5 min runtime at full load, because the small 12V 4Ah battery just do not perform well at 30A load.

If you are feeling patient, find a heavy, old, UPS second hand from surplus stores, Good Will, etc for next to nothing, then order new batteries from http://www.gruberpower.com. In the end, it might cost close to a new one with similar VA ratings, but you usually get way better runtime. You can take old battery to local batteries plus and they're usually willing to get rid of them for you.

I have an APC SmartUPS 2200va. I wouldn't use anything less; they're in a different league.


The SmartUPS units are more expensive than back UPS and lesser non-APC units because they are built to higher tolerances and produce true sine wave outputs, not approximated sine waves which can cause problems with surge protectors and sensitive electronics.

My SmartUPS last had the batteries changed in 2003 and they are still in good condition. It's well over 10 years old and still works flawlessly. It's truly a commercial grade unit.