Is it one of those real small "surge strip" style ones like this?

http://explorerscomputerjm.com/pc/ca...111_detail.jpg

Or a real-deal awesome UPS that weighs 100lbs, like this:

http://wireguided.files.wordpress.co...06/apc_ups.jpg

The cheap little ones are not worth it. Make sure you have one that does "live line and voltage conditioning" and is not a "part-time" unit. The amount of time it can keep the system going is purely based on the size of the unit, and the wattage/consumption of what you have connected to it. My huge unit can run my entire setup (firewall, DSL modem, PC, 20" LCD Monitor, and a flourescent desk lamp + LED lamp) for about 25-30 minutes in an outage.

Don't hook your laser printer up to that 750. I have a 1000 just like that, but have it hooked to two external 12V batteries, so it weighs quite a bit less.

I have a 3.6KVA unit in the basement, but I haven't powered it on in about five years. It takes 72V, which is six 12V batteries, and I don't have them. The ones I did have went bad.

It's a "Back-ups pro 650". Not quite as big as the one in the picture, and it weighs about 40 lb. I selected it to run the computer and the monitor..........and it appears to be fine for that. However, I'm not understanding the lack of capability to handle a line voltage drop without a reboot of the computer.

Switching power supplies (the type used in PC's) must have a continuous input wave in order to produce output. In other words, they don't have the "flywheel effect" that analog power supplies had. If a switching power supply loses the input wave for as little as a half cycle (that's 0.008 seconds), that can be long enough for the power supply output to drop low enough to cause the computer to reboot. Basically, a momentary interruption of the AC waveform may not leave the UPS enough time to sense the drop, kick in the relay, and start outputting sinewave (or something close to it) before the computer's power supply stops putting out its DC voltages. In some cases, a small UPS with a small but fast relay may protect against momentary voltage drops better than a big honkin' UPS with a bigger but slower relay.

(That explaination paraphrased from Richard Oldenburg, co-inventor of the switching power supply).

I don't have a 750...I was just using that pic as an example. :D

I actually have an XS900....its capable of handling my small laser printer, but I suppose my HP 4050TN might injure it. :D I'd never put a printer on a UPS though, not necessary at all. Surge protection is plenty.

Interesting....I suspect the unit may be malfunctioning. I have a 650, 350, and 550....all running at my dad's house protecting various pieces of equipment, and they all record even the most minute power fluctuations....including voltage drop...they'll just go on battery for 5 seconds and record the event.

I did have one that was going bad (a Pro 1100) and it would shut off when the power went out....I promptly replaced it.

Does yours work right if you just yank the plug on it? Or does that make your PC reboot too? I suspect it has a failing converter inside if it can't maintain clean power. Perhaps seek warranty with APC if its not too old. Otherwise, you can do a "trade-in" with them and get a discount on a new one by giving them your old one.

That's precisely the problem. I purchased this larger UPS for the specific purpose of being able to operate this computer in a thunderstorm. Apparently, my expectations were unrealistic.

Are there any devices that operate through a battery............the computer is powered by the battery and there is no requirement to switch to the battery?

The entire concept of "battery backup" appears to be complete BS if the computer reboots prior to the battery taking effect. What would anybody need a battery backup for...........if all their data is now lost??

All of the better APC units operate through the battery. I suspect yours has failed or has a fault causing the re-boots.

Thanks. This one was a "reconditioned" unit from e-bay. Last time I do that.............:rolleyes:

It will still qualify for a trade-in with APC on their on-line store.....at least you can get a discount towards a new one. :) And they give you a pre-paid return label to slap on the box and send back the old one....so you don't have to deal with disposing of it.

My one that I have I bought on-sale at CompUSA almost 3 years ago....so far so good...original battery still passes the self test.

Out of all the APC units I've worked with, I've only seen a few that failed "early"....and they were usually ones that were constantly having to switch to battery because of bad power conditions.

Thanks again...........I'll do that.

I know. Most desktop computers will still work properly with a UPS, but, undoubtedly, some combinations of UPS's and computer power supplies just won't play well together. I ran a 386SX machine with a small UPS as a packet cluster node years ago. That thing would go for over a year without a reboot, through all manner of Texas thunderstorms. No way I could duplicate that with modern consumer grade gear.

I have been using exclusively laptops in recent years, so, no more UPS issues, as the laptop runs off battery power, and the power supply merely charges the battery.

I haven't investigated UPS's lately. I would imagine that there must be commercial grade UPS's with very fast switchover time. Otherwise, like you say, What good are they?

I have an APC unit as well and it hasn't failed me the 3 or 4 times that we've lost power while i've been on the computer.

Most of the house electronics are fine during thunderstorms but our satellite dish always seems to get whacked during big storms. Thankfully new LNB's are pretty cheap so we always keep a few spares around.

http://img193.imageshack.us/img193/9157/dsc00108ptt.jpg

That's one heck of a satellite dish....are you involved with NASA? :D Or are you just trying to obtain every channel possible. ;)

Good units don't really "switchover".....they only have issues if there is something wrong with the electronics internally, causing poor quality power output.