Can any ups provide above watt rating wo auto shutting off (when on mains ac power) ?

[Anonymous user]

hi,

i have quite a few enterprise as well as consumer apc units in service due to my job (enterprise it and network support).  In these scenarios I would never consider overloading a ups beyond * 70% of its rated battery capacity.

HOWEVER,  my personal home PC rig has 3x 290x (amd) gpus, -  the rare times I play a high end game, my PC alone (no monitors, just PC) can pull nearly 1400w from the wall (I have a 1650w psu) - this will cause even a 1300w ups to start beeping and then shutoff (as designed, with no actual wall loss of ac power, just the ups auto shutting down due to overload) .

my Question is that 99.9% of the time I'm not playing a game and my PC alone will only draw between 250 to 300 W from the wall. So those are very rare times that I'm playing a game and drawing nearly 1300 W - if (during my rare gaming sessions) the main AC power were to fail  and my UPS batteries could not support that load, I'm totally fine with losing total power. However the 99.9% of the time that my PC is drawing less than 400 W I would like it to be protected from power loss (i.e. Web browsing , working or just the idle PC).   Given my scenario, short of spending nearly $1000 on a UPS, even spending $4-500 on a UPS causes more problems than it solves (as I do play games more often than my wall ac power fails.)

 I'm hoping there is some type of solution (or specific type of ups) that during an over wattage event, the UPS simply does not provide battery back up but also does not auto shut down (ie it functions as a normal power strip) .   Does anyone know of such a solution? Or perhaps a manufacture who's battery back up does not shut down in an over wattage scenario (but of course, it also won't provide any runtime during over wattage- or even better yet moves the auto shutdown logic to the battery inverter,  such that if you draw too much when the battery inverter is on/active then it shuts down versus shutting down if you draw too much from the wall, when the wall is clearly capable of providing that power (which is what your home breakers are for) )

 The only other solution I can think of is to look into some kind of quick AC transfer switch that allows me to bypass the UPS and go straight to the wall which I would switch right before I were to play a game (in other words the equivalent of shutting down the PC moving it to the wall starting it back up playing my game and when done  shutting down and moving the PC back to the UPS) 

 Although I don't agree with the reasoning, I do understand why UPSes auto shut down when you're pulling more than their rated battery capacity. So I'm not looking for an explanation of this logic but more so for any potential solutions to my pretty unique scenario ( IE, I need protection for the 99.9% of the time that my CPU draws under 400 W but at the same time a backup power source that does not automatically shut down when I'm drawing 13 or 1400 W for an hour or 2 , once every other month or so) 

Thank you!

[Brad_C]

I have an old BackUPS CS here that will scream blue murder if you overload it, but it keeps on supplying power. The beeping does get intolerable pretty quickly however.

Most sane UPS units I've worked with don't like being overloaded though. I picked up an AP7721 ATS that I interposed between a UPS and the IT equipment to allow me to perform maintenance on the UPS without disruption. Somehing like that'd do what you want. Alternatively an external bypass panel would be another option.

Personally I'd just go for a bigger UPS, but then I like lots of margin.

[BillP]

Hello James,

Thank you for posting your questions here on the forum. Just so that I can get a better sense of what you have (and to make sure we are getting you something better), what UPS do you have?

What plug does it have? I am assuming based on the power draw, that this is on a 20A circuit, correct?

Also, I'm just curious, how are you tracking power draw and know that you are pulling 1400W?

I myself am a PC gamer, so I completely understand (but my rig is nowhere near as awesome as yours).

Thanks,
Shanon

[voidstar_apc]

I'm curious what Shannon comes up with, but just wanted to provide a bit of the bigger picture. What you want is reasonable, however one issue is that UPSes transfer to battery temporarily due to any disturbances on the line, not just power failures. This is because the UPS needs to react before attached equipment detects loss of power. Could be inconvenient if you're playing a game at the moment.

[Anonymous user · Accepted solution]

APC used to sell a device that would let you "hot swap" a UPS without cutting power to the attached load. I believe the model number is AP019. I don't know if they still sell anything like the AP019 as a current product. I think it would do what you want: let you run the computer with backed up power when you're not gaming and run directly from the wall outlet when you are. There is a manual switch right on the unit.

(Caveat: the AP019 I have indicates a maximum rating of 12 amps. At 1,400 watts you'd be running right up against 11.7 amps worth of current drawn.)

I'm not aware of too many UPSes that will let you overload them by any appreciable degree before they shut down. (The older CS350/500 models as mentioned previously are a good example of units that will stay on even if heavily overloaded. I believe that to be a lot of the reason why they were recalled.) And as you note, it's definitely not nice to push one right up to its limits. If you wanted your computer to stay up during power failures when you are gaming, I think the smallest suitable UPS APC sells would be the Smart-UPS 2200. While rather expensive if you were to buy one new, a lot of good used examples are free for the asking or very cheap when the batteries conk out.

Getting one of those would give you the advantage of a computer that stays up for hours when it's not being used for gaming purposes.