why in gods name cant companies design products to work with as little cooling as possible? why must they design these pieces of crap with almost no possibility to move air through, to have a small, high RPM fan that is whiny and continually speedchanging. and it pushes that air through a plastic housing, with very small slats... am i the only person who sees how ridiculously STUPID these designers are? it's not just cause i'm a niche market. this thing is unacceptable, end of.

this is unreal. i bought this ups around 3 months ago, and it's always been audible. the fan NEVER turns off.

but now, all of the sudden it has decided to cycle up and down constantly. for no reason at all. my usage patterns haven't changed. my computers haven't changed. but for no reason, the fan will just cycle up and down.

i will never buy another APC. or any other manufacturer that makes UPS like this. who puts something that needs active cooling in a PLASTIC HOUSING? who forces air through VERY SMALL SLATS? it's just absolutely retarded.


sorry about this thread, i just needed somewhere to vent. i'm pissed off that this 120 dollar ups is now a 120 dollar brick..absolutely useless to me.

I have several APC UPSs for a long time and the most noise any of them make is a muted humming as they recharge. You may have a defective unit. What model?

Back-UPS XS 900VA

The only time fan comes on in my APC UPS is when there is a power outage and it's working. Supposedly it helps battery life to keep it cool.

I think you got a defective unit there OP.

PS on a side not, my APC UPS also has moderate humming. It's inaudible during the day, but I can hear it during the night

All of the UPS' i came across have a humming, which is why i don't use any. What are the odd of having a power out while i'm doing something massively important that i can only do on my PC anyway?

pretty good when you live in a neighborhood where the power will dip below acceptable levels for the comp every time someone in the neighborhood activates their air conditioner.

at least, that's the problem we have here. voltage will drop to below 100v when AC's kick on. and that's what was causing one of my comps to click off.

The XS900 fan is always on (see my post from a year or 2 back). That's the way it was designed....don't ask me why. It's the loudest component in my room (when the furnace isn't cyling on). Mine does not cycle the fan up/down, though. Send a message to their customer support. I think it's got a 3 year warranty.

Other than the fan, it's been a great UPS for both controlling noise events as well as power outs. Given the high wind/storms we've had here, I am damn glad I have a UPS.

I haven't noticed that kind behavior in neither APC Pack-UPS Pro 650 or current MGE Pulsar Evolution 1500. (whose only noisy thing was very annoying 60mm fan... now there's 80mm fan in adapter)

I solved a similar issue with a APC 2200XL I bought used. The high speed fan would activate every 40 minutes for 30 seconds and blow a little hot air. The noise from the high speed fan was unbelievable. This is under low load.

I installed a 120 MM DC fan on the outside case air exhaust holes. It has an ac adapter that plugs into the UPS and 5 speed settings. Since I installed it, the UPS only activates for 5 seconds whenever I start my printer from the same circuit. I can barely hear any of the fans now. It is just enough to keep it cool under normal operation.

In response to the OP's question about why have a plastic housing, and small fans with little ventilation.

Its all form over function. Ever since the iMac things have started looking cool for the sake of it. Your PC and associated equipment all has to look cool these days. Otherwise.. well.. its not cool!

The solution for that is to get an APC BE325 preferably on sale or closeout somewhere for $20. It won't keep your PC up long but it'll protect you from those 2 second dips for years to come.

If you are using it that way you don't bother to put the monitor or printer on it. Just the PC and your switch/router/cable modem whatever you are using for connectivity.

It isn't about keeping them up for long periods, its all about keeping them from rebooting when the power goes out and comes back on so fast your eyes don't even hardly recognize the lights were out.

Oh and for the record it doesn't even have a fan. It's fanless. You'll hear a mild buzz from it if the power goes out but it's quieter/smaller/cheaper than any other UPS I've looked at...

I have the same problem with the Back-UPS XS 900VA. I find the limited airflow design that requires a constantly on fan to be completely unacceptable. The level of noise and high pitch coming from the fan is very annoying to the point that I am going to buy a new unit.

I need one with at least 520 watts of power. I don't mind a unit with a fan because I've heard of UPS's bursting into flames, so having heat monitoring is fine. I just want a unit that allows for adequate airflow and a fan that only runs when it needs to.

Any suggestions would be appreciated.

I just ordered a dozen 550VA Back-UPS ES APC part number BE550G. I'll let you know if it isn't but I'm assuming it doesn't have a fan. In fact from the pics I've seen I'm assuming the 750VA model doesn't either.


BE750G

BE550G

Curcuit City wouldn't let me order more than 3 of the same UPS so I went with nextwarehouse.


btw APC lists the Audible noise at 1 meter from surface of unit
45 dBA on your XS 900A

45 dBA on the 750 I mentioned

and

45 dBA on the 550 I mentioned

I should have them in a week or so and I'll let you know if I hear them at all.

fyi - APC's tech support does respond. If you have a question regarding whether a model has a fan and when it turns on, you could always just ask them.

OK, the BE550G units came in. I switched mine out today and haven't heard a peep from it. I don't see any visible fan intake or exhaust port so I think the 45dba spec on this unit is just a typo. I put my head next to it and couldn't hear it at all.

If there is anything on this thing that is 45dba its the beeping alarm for when the power goes out.

I purchased an APC RS 500 about 2.5 years ago. At the time, it was the best bang for the buck among their passively cooled models. UPS is definitely one of those things you don't normally think about, but does certainly make a difference. Since I just wanted something to cover me through the momentary drops we get here. They're usually a half second or so - just enough to flicker the lights and for me to hear one beep out of the UPS kicking over to battery power, then back to A/C.

I've used it for a week and have even had 3 or 4 plugged up charging at the same time and can't hear them in a quiet office setting.

I think it's safe to say the 550VA and lower units are fan free.

There are two major categories of UPS: Offline and Online.

An Offline UPS simply passes electricity through during normal operation, and instantly switches to battery when the mains power goes out. Because this type of UPS basically acts like a power strip most of the time, there's no need for cooling during normal operations; the cooling fan only activates when the UPS is running from battery. Most of the cheaper, lower-capacity supplies are offline.

An Online UPS also acts as a very effective power conditioner. There is no direct connection between the mains and the load; the mains charges the battery continuously and the load is driven by the battery. These tend to be more expensive and carry higher power ratings, and are generally used in industrial or critical areas, or places with exceptionally poor mains power. Because the charger and inverter are running at all times, active cooling is required at all times.

I've seen quite a few people on this site complain about a loud UPS, and I can only find two possibilities. Either they've got a defective unit (in which case they should contact the manufacturer), or they've bought a UPS which is complete overkill, especially for a typical cool-running SPCR computer. Figure out which category you fall into, and the solution will be obvious.

I've got an APC NS650, and it's dead silent under normal conditions. During a power outage, it's pretty loud, but at that point I'm willing to accept a few minutes of noise. I've never even noticed noise during charging, but I've never fully depleted it so it's never had to charge for very long.

It would be really cool to have an online UPS and a PC PSU co-operating, so that the PSU would feed directly from the UPS battery, without converting to 230V or 110V AC in between, making it more efficient.

Laptops of course, but is anything like this available for desktop PCs?