I didn't really understand how do UPS work...

http://bit.ly/1c1PImy

It would be helpful if you put some information with your question, like what make/model your UPS is. And with UPS units the battery life all depends on how much load your system is running at. At full tilt, with that kind of rig, it would probably last 5-10 min, my guess.

Typically some outlets on the unit are for surge protection only, and some outlets have surge protection + battery backup.

well... i'm using a xs1300 (1300va/780w) with an i7-920 with 470gtx
at idle i can get about 10-12 minutes of use. at load i can get 3-6.
it allows you to shut down your pc in the case of a power outtage (to avoid a hard shutdown) and protects you from surges and brownouts. not much else. dont expect to run a pc for hours on it. you would need a much bigger battery for that.

generally only a few of the plugs on the rear are for "battery backup" and will be powered by the battery. they are clearly labeled. the rest are just ran through the surge protector and in case of loss of power will not function.

by numbers on screen i suppose you mean that it has a lcd screen. generally they display your current usage in watts, %load, estimated time the battery would power in case of power failure among other things.

if you want any more details you would need to go looking up your model and reading the manual. we arent mind readers and since you gave us no specifics we can only tell you the bare basics which applies to all models.

No computer is creating so much heat as to also toast bread. A 500+ watt supply is what we tell computer assemblers to install when 250 watts is enough. Additional facts apply making it too difficult to explain to computer assemblers how to select a PSU. Brand name systems can use much smaller supplies since engineers know what is really important (not watts). But we tell computer assemblers to buy a supply double what a computer will consume - a 500+ watt supply. Meaning we need not teach electricity concepts on help lines.

A UPS will degrade quickly in three years. If a system needs 250 watts plus monitor and other peripherals - maybe 300 watts at most - then a UPS must be sized for that degradation and other factors. Therefore at least 600 watts is recommended. Larger simply means it would provide temporary and 'dirty' power longer during a blackout. And be more expensive. But it will still degrade in an expected three years.

A USB port is how a UPS tells a computer that AC power has been lost. Gives a computer time to save unsaved data. That extra time is the primary purpose of a UPS - so that unsaved data is protected. Unexpected power off does not harm hardware or already saved data.

Temporary and 'dirty' power is created by its battery when power on AC mains is lost. Those are battery backup connections. 'Surge only' is a direct connection from those receptacles to AC mains. If AC mains power is lost, then so is power to 'Surge only' receptacles.

They hype a word surge. But read its specification numbers. Its surge protection is near zero joules. Just enough above zero so that advertising can hype it as 100% protection. Anything connected to those 'Surge only' receptacles is directly connected to AC mains.

@westom

1. we are sizing a ups not a power supply. while i did not cover it you are correct that power supplies typically used on the consumer end are larger than required. however also realize that power supplies used in many retail computers (like dell) have zero upgrade room which is a bad thing. of course this is unrelated to the ops question. what matters most is what the computer actually draws in watts at both load and idle.
2. batteries in the ups do degrage over time. this is a given constant and every few years you will need to replace them for optimal peformance.
3. what usb port? while i might not have seen a wide range of ups products i havent seen one with such a feature. i do agree that it gives you time to save data however it is not true that a hard shutdown is not capable of causing harm. i've had ram sticks die because of a user doing a hard shutdown under load instead of shutting down properly. i've also had other issues. its not guaranteed but its definitely a risk.
4. perhaps you are unaware that ac power can be "dirty" as well or that many ups models correct sine waves to clean power up? perhaps you are also unaware that some models have surge protectors on both the battery backup and surge only connections. its a given that you lose the surge only connections are lost (hence why you would connect to the battery backup ones)
5. not sure about all backups but mine is rated at 340 joules surge protection. certainly not zero though i do agree it is nothing compared to traditional surge protectors. in any case they could be used with traditional surge protectors as well as traditional circuit breakers. its often recommended to have at least 200-400 joules (the ups fits in there) although greater (600+) is recommended.

never heard of wortex.

i personally use apc so can say they provide a decent product. other than that i cant really say.

i've heard 3rd hand that cyberpower has decent ups but i cant vouch for them myself.

what sort of backup runtime are you looking for? if its just for a few minutes then something like i have will work. if you want something that gives much longer runtimes you might be better off with a bank of car batteries and an inverter.

The general recommendation to double the size of a power supply compared to the stated use (which incurs another safety factor) is generally because across the majority of industry as a whole cheap she at
supplies are used. Obviously, this is self defeating because a $3 tin box from china that has 400watts written on the side still isnt reliable for a 130 watt pc, so when somebody tells the guy in china we need FIVE HUNDRED WATTS he gets the guy in despatch to print
500 WATTS
on the boxes, and charges $3.50
Change subject;
Cyberpower assemble pants pc's from batches of components bought at clearance often resulting in components that dont even match;
i.e. K series chips and h61/81 chipsets. There is no way on the planet these people could set up a manufacturing facility for an uninterrupted power supply, and if they could I wouldnt have one in my house.
Cowboy outfits vanish in months and they are no exception.

A more reliable way to protect your current work would be to network a laptop,plugged in to the wall. If the power went down you would have an hour.

@ssddx
You would tell an engineer who did this stuff for decades (even before PCs existed) that you know better? And then deny reality without even one number? Gauling are so many denials without any numbers. A first indication of junk science reasoning is claims without nuimbers. Please do not show disrespect.

If a hard shutdown (sudden power loss) is destructive, then listed were damaged parts and manufacturer spec numbers that define that risk. Prove me wrong. If sudden power loss is destructive, then cite the 'at risk' part. Not "I have observed" reasoning. That is classic junk science. Please explain why sudden power loss is destructive - with reasons why and specifcation numbers. After so many generations, I have never seen it.

An international design standard even 40 years ago required low and no voltages to cause no electronic hardware damage. That requirement is found in all our designs. Standard even included this expression in the chart - in capital letters: No Damage Region. Why do design standards disagree with popular beleifs? That answer applies here. UPS to protect hardware from sudden power loss is not based in hard electrical and design knowledge.

Hearsay claims 200-400 joules protection is sufficient. A 200-400 joule surge would not damage anything - except maybe that grossly undersized protector. Undersizing gets the naive to recommend the undersized and then damaged protector. Yes, a majority might believe 200-400 joules is sufficient. Then a majority also believed smoking cigarettes increased health for the same reason. Because advertising said so. Advertising and hearsay are a most common reason for recommending a UPS to protect hardware.

Hearsay also claims a sine wave UPS. If a typical UPS outputs 'cleaner' power then manufacturer spec numbers (ie %THD) are also provided. No %THD number means speculation can promote a myth. Most see the exprexssion "sine wave" in sales brochures to assume cleaner power. Why destroy the myth with a spec number such as %THD?

A utility demonstrates outputs from a typical UPS in TechTip 3:
http://www.duke-energy.com/indiana-large-business/business-continuity/power-quality/tech-tip-03.asp.
Let's be clear about it. Those 'dirty' waves are "sums of sine waves". Did the utility invent a myth - or get facts using test equipment? Where is this 'clean' power?

Leftmost wave is power direct from AC mains. Followed by a switchover to battery. 'Dirtiest' power is often from a UPS in battery backup mode. 'Dirty' power that does not harm electronic hardware. Because hardware is so robust. However, that same power may quickly degrade a 300 joules (undersized) protector.

Near zero surges (ie 400 joules) are also made irrelevant by robust hardware. Above cited international design standard even required 120 volt electronics to withstand up to 600 volt transients without damage. Another number that contradicts popular hearsay.

Challenges are posted. Cite the part damaged by sudden power loss. Provide manufacturer spec numbers that justify that rumor.

Second, show why cleaner AC power is necessary when 'dirtier' power from a UPS is not hardware destructive.

Third, explain how 600 joules can make destructive surges (ie hundreds of thousands of joules) irrelevant.

Another problem with undersized (ie 400 joule) protectors. House fire. Reasons why (near zero joules) explain this threat.

UPS purpose: temporary and 'dirty' power so that unsaved data is not lost during a blackout.

Explained previously for the OP is why a minimal UPS (probably) would be 600 watts. What those various connections (battery backup, surge, etc) do. And why so many myths promote a UPS to do what the manufacturer does not even claim. UPS is for one anomaly: temporary and 'dirty' power during a blackout.

@westom

i could sit here an argue with you but its not worth the effort and doesnt help the op at all.

if you want to be truly helpful you could try explaining to the op in a simple manner if their product will work or not.

i'll stick with my own ups which has worked flawlessly for years and through 15+ outtages and you can dish out whatever advise you want.

i'm giving you 100% liability for this thread and the advise within. please do enjoy.

Actually, electronic switch gear components in any circuit involving a ballast or coil can be damaged by hard shut downs unless they are protected, as when the E.M. Field collapses it turns back into higher pressure electron movement from whence it came and every other direction come to that. Get a room you two.

Was done at least twice. But again:


Typical UPS is only for a blackout so that unsaved data is not lost. Other anomalies require different solutions. Are not solved by a UPS. Or are solved by what already exists inside electronics.