abhijith

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I have a 600VA UPS. I want to know whether it can run a 600W power supply? If not then what is the maximum it can handle?
 

cliffro

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600va = roughly 360w

1000va = 600w
Going by APC and Ultra.

Some other unknown brands show 850va @ 600w but it would have a very short runtime.

Of course I only use mine to add extra surge protection, mine is 350va, and when the battery was new, I had plenty of time to shut down if the power went out.

Just looked @ APC's site, An APC Back-UPS RS, 600 Watts / 1000 VA


Typical Backup Time
at Half Load
17.9 minutes (300 Watts)


Typical Backup Time
at Full Load
6.3 minutes (600 Watts)
 
Just some additional comments to cliffo's excellent info.

Do not confuse Max PSU ratings with max Computer Power consumption. IE - I have a 850 W PSU, but my computer on draws approx 320 Watts max (approx 200 Watts at idle) Plus what ever the monitor draws. The 320 plus Watts are what is important and determines the run time

Just max sure that you do not exceed the Max Wattage rating, Then select on run time that you are confortable with. Most UPSs comes with software to automatically shut down PC.

Just for info. I normally ignore VA ratings. This rating is more important for reactive loads where the Max Voltage and Max Current are out of phase. Good computer PSU's hace a PF close to 1 (Resistive load) where Max Voltage and Max current are at the same time. Reason Wattage rating is the Key value.

Another reason to pick a good UPS is the output waveform when on Battery power. Cheap ones have a Pis*Poor output that can be very noise.
 
abhijith.
I quess your real question is in changing the PSU, Do you need a bigger UPS. There would be very little difference in using a 450 W PSU vs a 600 W PSU and you would see very little change in run time and no reason to change your UPS.

Now if you are changing the PSU because you upgraded your graphics card to a higher performance card, then your run time will decrease.

Andy,
Your link provides a good explanation and is the reason in selecting a "good" UPS.
Personally I prefer a UPS that has a CONSTANT regulated AC output, But alas they can be expensive. The one I bought for my 386-SX was $450 (Bit the dust after five years), hate to think what a new one would cost .
I'm well versed in PF = True power / Apparent Power or PF = Cos of Angle. And yes Inrush current is a major concern. It's a pain to measure. I say this from having to perform the measurement for Satellite instruments. I use a dual trace capture scope triggered on voltage (Trace 1) to capture the current pulse (trace 2).
 

abhijith

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I was thinking of upgrading my power supply to a 600W so that I could run 2 4850 in Crossfire. I wanted to know whether the UPS would work with a 600W power supply.
 
1. Make sure you get a GOOD psu. There are countless posts on which PSU's are good choices. Make sure you read some of them

2. Your current system probably only draws about 175 Watts at Idle Plus what ever the monitor draws say 40 Watts for a total of 215 Watts, And when you game that probably jumps up to to around 300 Watts Max which is fine for your current UPS. Throw in another 4550 and that puts you around the 375 -> 400 watts when gaming. This may be cutting it a little close, Would probably be OK until you save up and move to a 750 -> 850 VA UPS

For comparison: My system (Excluding monitor) Idle around 200W and 320W at max load (3d game)
E6400 @ 3.2 GHz
GPU 4870 w/512 megs ram
Memory 4 Gigs
HDD: 4 ea.
1 DVD writer
1 Blu-ray Writer
5 Case Fans.
 

croc

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I think a lot of posters here are missing the point, really. It is not the output watts of a PSU that matter, it is the input amps that the PSU requires to produce said output. So, every toy that I have plugged in to my UPS (PC, monitor, partner's laptop, two PDA's and a mobile phone) draws ~2A from the wall. My PC isn't the most powerful PC in the world, but that measurement was taken while playing Crysis demo, all settings forced to high. My 1kva UPS has a typical runtime in excess of 30 minutes. Oh, my PSU is an antec neohe550, input rated at 9A. Maybe I should say over rated...
 
abhijith -
(1) You ONLY need to plug The computer, monitor, and external HHDs (ie usb devices that require external power) into the "Battery" outlet on the ups. Other devices can be powered from the "Surge protected Only" outlet, or they can be placed on a seperate Surge protector. Remember the Purpuse of an UPS is for orderly shut down, NOT to continue gaming.

(2) Your computer + monitor + USB Hard drive is Not going to require 500/550 Watts even with 2 USB Hard drives.
(a) Computer less graphics card - I would say approx 100 W (My best est not knowing your complete setup)
(b) 4850 GPU - 50 Watts Idle, 110 W gaming (double for 2 4850's)
Combined - Single GPU, Idle Approx 150 W, Gaming - approx 210 W. For two 4850's, Idle 160 - gaming Approx 320 W
(c) approx 50 W for LCD (Need to Check Data on back of your Display - And NOTE you will be less than what it says!
This yields a MAX power of about 475 W (using 75% eff for PSU)
URL for GPU power consumption

www.tomshardware.com/reviews/geforce-radeon-power,2122-6.html

(d) Cannot stress the importance of choosing a "Good" PSU

Added - good starting point:
www.tomshardware.com/forum/259002-28-will-modular-power-supply-enough. End added

Croc -
You are absolutly correct - It is the TOTAL power consummed by the devices(s) pluged in to the "Battery" protected side. WHY would you plug in a device that already has an internal battery (ie laptop with battery installed) into the "Battery" side and not the UPS output that only provides Surge protection
- And for them you could also simply plug them into a separate surge protector.

NOTE If you drew 9 Amps for more than 50 millisec, something is fried, 9 x 115 = 1035 WATTS. PSU is only ratted at 550 W. if MAXed out (Very unlikely) your input current would only be 6.4 A, assuming 75% PSU eff.
 

croc

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RetiredChief -

If my PSU drew 9A @ 240 VAC, that would be 2160 watts... So, as I said, the input amps rating on my PSU were a bit 'over rated'...

My partner's laptop is plugged into the battery side of my UPS because my APC Smart-Ups 1000 only has battery-side connectors. In our part of Sydney AUS we get some really nasty brown-outs, blackouts and then the surges post-fact. So I plugged her laptop into a UPS protected circuit.
 
croc
Yep, 9 A @ 240 is way over rated, Just a question is that rating for 240 or 120 - the reason I ask is that alot of electronics are either switched, or auto, dual voltage and they provide the current for both ( 1/2 Amps of 120 VAC at 240 VAC)

On laptop into UPS, you have good rational. Seams some else from "Down Under" metioned excessive brown outs/ black outs. Could have been you, been quite a while.

On your smart Ups. Is it continous regulated, or the more common switchs on at -10%. Reason I ask is if it is the later you might want to get the "Always regulated" type if you have alot of brown outs. As I said they are Expensive and normally have shorter runtimes. Reason is that the output can be pretty ugly when they switch in and out. I've looked at several with an o'scope

Take care
 

croc

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That particular model is completely isolated - hence no outlets for surge protected. It also has a pretty good waveform, one has to switch down to 1 millisec scales to see any stair-stepping, and down to 50 microsec to get a good look. As it should be, given what I paid.

I've never seen a PSU with adequate input labeling. Must not be important enough to consumers for MFGs to care... And I've seen output ratings that added up exceeded the total wattage by as much as 30%. Go figure.