Choosing a UPS system for my computer.

I figure since i just invested a couple grand into a new computer its probably high time i get a legit ups system to gelp protect it. If i want to give myself enough wiggle room to safe shut down my computer and a monitor while also giving myself brownout protection for my routing hardware and computer with 3 monitors. How do i figure out what size i need?
 
UPS devices are rated with "VA" and "Watts" as well as a run time at full power. The VA is an annoying number that is only useful when comparing UPS against each other when you don't already know what you need. The watts is the maximum power your UPS will support when power goes out. So take your computer's power supply (say, 600W) and your monitor's power supply (say 200W) and you should get a supply that will support at least 900 watts. After that, check the supply's run time at full power and choose one that gives you enough time to exit your game, save your files, and turn the computer off. 2-5 minutes at a given maximum wattage is normal.

Here's where it gets sticky. They are generally considered "emergency" backups. If you use one to its full capacity and drain it until it shuts off, you've almost certainly damaged the battery. The lead acid batteries aren't happy if they're every discharged below 50%. On top of that, even under normal usage they will degrade and you should expect to replace the battery (or whole UPS) every 2-5 years. Because of the first issue, you might want to get a supply that has double the capacity if you want to use the UPS frequently.

If you are also dealing with brownouts, surges, or other power problems and frequently have electronic devices die due to power issues, you might want to look into "online" UPS supplies, vs "offline". Online means they are always powering your computer with the converter, supplying a constant source of good power directly from their inverter regardless of the AC power coming in. Offline means that the converter is inactive until the power goes out - in other words they just connect the computer to the powerline as long as there's power, and then switch to the converter when the power goes out. The online UPS supplies therefore absorb any brownouts, surges, and other electrical problems and your computers never see any of that. Good offline UPS supplies also provide some amount of filtering and protection, but eventually such protection wears out, and isn't as bulletproof as a good online converter.

The cost difference is very high, though, so I wouldn't recommend it unless you know your AC supply is terrible.

Beyond that, make sure you test frequently once you have one. And not just using the "test" button, but actually unplugging it and making sure it'll power your system for the several minutes you need. Otherwise you're going to be caught short when the power goes out and you didn't realize the UPS was in bad condition.
 
So my power is very reliable as my home shares a substation with a set of prisons. We have a modern 35k 3 arm transformer on the pole and i have a high gain surge protector. But now im not sure if i should invest in a ups?
 
So my power is very reliable as my home shares a substation with a set of prisons. We have a modern 35k 3 arm transformer on the pole and i have a high gain surge protector. But now im not sure if i should invest in a ups?
-There are three main types: Offline ("standby"), Line-interactive, and Online. @stienman already talked about two, the middle one is mainly an attempt to compromise price/benefit in the middle of the two.
-Another thing to consider is whether or not you want a pure sine-wave UPS or something that approximates a sine wave ("stepped"). If your power supply says it is an "active PFC" power supply, then you probably want the pure sine version, which unfortunately does make it more expensive.
-Also keep in mind that you should not use a surge protector on either side of a UPS. This is important because it's hard to find power strips that don't also have built-in surge protection of some sort.
-If you don't already have something like a Kill-O-Watt to measure your total required power draw, then you will have to estimate by totaling up your components. There are plenty of load calculators on the Internet that'll help with that. This is probably the toughest one to figure out, because translating between "Watts" and "VA rating" is confusing and nobody seems to want to make it easier. I will say this, though...you want to get some noticeable extra capacity above what you need, because running a UPS at 100% of its rating is inefficient AND it will limit its runtime. As an example, a general rule is that if you use a UPS that is twice as big as what you need (1200VA instead of 600VA, for instance), you won't get double the runtime, you'll get triple the runtime. The harder they hafta work, the quicker they run out, so if you want a long runtime (to be able to save your game and shut down, or something), that means you're going to have to overbuy on capacity BUT still keep it within what your home circuit can supply (most home circuits only supply 15 Amps shared between everything on the same circuit).

--Patrick
 
Total usage on circuit for components is about 1100 watts, is a dedicated 20 amp circuit with qo breakers
 

GasBandit

Staff member
Steinman and Pat have given you very thoughtful, tech-minded answers.

Here's mine, which is not so much.

I run my gaming rig on a $50 UPS. My area has frequent brownouts and power outages. My UPS generally dies permanently every 2-4 years. When it does, I buy another $50 UPS. I don't think its wattage comes even close to what I pull (I think it is rated for 200, and I have an 800w power supply plus monitor, external hard drives, etc). Generally it lasts less than 3 minutes in a blackout, but despite being of the "offline" variety, it does smooth out the "dips" when the lights dim or flicker.

But as I said... every 2-4 years... all of a sudden you'll hear an alarm constantly going off in the middle of the night/when you come home from work and all your stuff will be without power.
 
To be fair, I've been looking into this a lot lately, because I want to get a UPS big/reliable enough to run the 4 computers + switch in the living room simultaneously.
And if you get a decent one, the alarm will just be the one telling you it's time to change the battery, and you won't be without power unless the circuit itself has no power.

--Patrick
 
the most affordable one I have found so far is a cyberpower unit that can handle 900w and 1500Va.
I imagine the size Pat is looking at probably costs as much as my computer.
 
I imagine the size Pat is looking at probably costs as much as my computer.
Surprisingly, the price I'm seeing is more $350-$400. I don't need anything as huge as you might expect, since it's rare that all 4 computers are running full-bore at the same time.
Still more than I really want to do at this time.

--Patrick
 
Yeah i can see that. I just want mine to absorb rolling power and safe shut down during a storm blackout.
 
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Then get something that's sine wave and rated for +20% your current total load.

--Patrick
im sorry man, i feel like i pissed you off, i think i have it figured out. i was just commiserating about needs for these expensive pieces of tech.
 
im sorry man, i feel like i pissed you off, i think i have it figured out. i was just commiserating about needs for these expensive pieces of tech.
Nope. Not pissed off. Just trying to be succinct.
I don't think you know how difficult it is to piss me off.

--Patrick
 
I'd say one thing of advice: your needs are not the same thing as your max power draw possible. Just because I have a 600W power supply doesn't mean I tick "600W" into my calculation. The wattage of your computer's PSU is always ABOVE what it will actually draw, or else your system itself is unstable. So odds are your actual draw is lower than what you're "rough" calculation is. And if 90% of the time you're surfing the web, your graphics card isn't drawing much, and neither is your CPU. And if your monitor doesn't have the brightness ALL the way up, again, it's not drawing max either.

So use some of the tools above (or an actual in-line power meter, which are cheap) to see what you REALLY need, at typical, and full (running whatever the most taxing game you have at max resolution) power consumption for worst-case.

Good luck.
 
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