uninterruptible power supply help

Soldato
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Seeing some of the abuse it has taken maybe not so surprising - I keep mine comfortably specced with overhead - infact probably a bit overspecced - the current estimated protection time for the two I've got in use right now is 2 hours 3 minutes and 20 seconds for one and 1 hour 20 minutes for the other heh.

That not my photo by the way, but saying that, I have plugged alsorts into it over the the years, evern a 24" crt tv when we had a powercut, so me and my family could watch the soaps hehe.

You must have a high wattage ups,, mine will only keep my pc going for about 30mins (about 150watts) and 1-2hrs if its under 50watts.. Im guessing a lot of battery power is used just by the ac/dc converter.. Im guessing it would last much longer if it didn't have to convert the power first?
 
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Was going by your description of some of the uses it had had.

One of mine has the networking hardware plugged in (NAS, switch, router, etc.) hence 2+ hours and 3D printer but I don't think the 3D printer (while active) is being calculated into that protection time. The other one of my PCs (and that is only the base unit not the monitor).
 
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That not my photo by the way, but saying that, I have plugged alsorts into it over the the years, evern a 24" crt tv when we had a powercut, so me and my family could watch the soaps hehe.

You must have a high wattage ups,, mine will only keep my pc going for about 30mins (about 150watts) and 1-2hrs if its under 50watts.. Im guessing a lot of battery power is used just by the ac/dc converter.. Im guessing it would last much longer if it didn't have to convert the power first?


Depends on VA rating on the UPS (and of course what is connected) If you have a 30,000VA UPS it'll last a long long time. 400VA? Not very long at all.
 
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Depends on VA rating on the UPS (and of course what is connected) If you have a 30,000VA UPS it'll last a long long time. 400VA? Not very long at all.

Mine is 1200va/650watts... Id love a 1500va or higher as that would keep things going much longer, but your looking at about £250+. Plus I bet replacement batteries wont be cheap for a more powerful ups?
 
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Yeah £75 fir two yuasa batts. Not APC as they charge 150 quid. But bought right model size batts from batt seller stuck them together used the brushing and fuse cable saved 50 %
 
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You must have a high wattage ups,, mine will only keep my pc going for about 30mins (about 150watts) and 1-2hrs if its under 50watts.. Im guessing a lot of battery power is used just by the ac/dc converter.. Im guessing it would last much longer if it didn't have to convert the power first?
Question is even more about battery capacity.
Server UPSes tend to have more of it.
Which is why they're usually lot bigger than consumer UPSes and especially extremely heavy.
Also often those have separate extra battery packs.

Like name implies AC/DC conversion is never run from battery, it's only needed for charging battery or in non-battery mode of double conversion/on-line UPSes.
But different inverters (DC/AC converter) can indeed have different efficiency depending on more precise design and components.
Just like PSUs have different efficiencies.
Then again most consumer UPSes actually have advantage in producing (modified) square wave which is simpler to make than sinewave.
Also just like in PSUs higher power output UPS itself tends to need more power to keep itself running.
Though better design and components can obviously help in that.

I myself have Eaton 5P 1550i (1,1kW) with 3x 12V 9Ah batteries and that 16kg weight is extremely light for UPS of that level.
http://powerquality.eaton.com/5P1550i.aspx?cx=101
60mm fan behind stamped mesh is just noise maker, so cut away that mesh and replaced it with adapter mounted 80mm fan which can achieve same airflow at lot lower rpm.
Likely actually improved cooling over original.


VA is maximum load rating, not necessarily runtime. Obviously a UPS sized for a bigger load will last longer, but normally to get extended runtime you buy additional expansion battery pack units.
Power rating is different thing from battery capacity.
And VA isn't even actual power rating.
It's apparent power unit and doesn't directly tell about actual power rating: watts
You could have many thousand VA load and if it were fully capacitive or inductive it would consume only minimal amount of watts:
Pretty much all electricity would be just "bouncing" back and forth between UPS and load.

While in the past some reactive power component was actually needed with active-PFC in PCs and all better monitors only watts are now meaningfull.
Of course marketers have just stuck to VAs because they give bigger number than watt rating.
 
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That looks like a quality ups EsaT, I would love one of those. Just looked on the bay and for £250 - £300 you can buy the 850va version

My ups uses the same batteries as yours, the 12v 9Ah, but only 2 of them.
 
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Hey this powercool ups looks very tasty for £150 - £200?

wi2cyx.jpg
 
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I have 3 UPS,cheap ones :D
on different pcs/components etc and never got any of the batteries to last longer than 3 years
But the actual UPS them selves seem to keep going,one of them must have had 3 changes of batteries so 9 years
 
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That looks like a quality ups EsaT, I would love one of those. Just looked on the bay and for £250 - £300 you can buy the 850va version

My ups uses the same batteries as yours, the 12v 9Ah, but only 2 of them.
That 5P's stock fan ain't pleasant unless you're using closed headphones.
Pictures of rear actually show what kind stamped mesh it has as extra noise source from turbulence:
http://powerquality.eaton.com/Products-services/Backup-Power-UPS/5P.aspx?cx=101

Ellipse Pro with standard modified square wave output is consumer/home use aimed and doesn't have fan.
http://powerquality.eaton.com/Products-services/Backup-Power-UPS/Ellipse-PRO.aspx?cx=101


CyberPower has one of the cheaper sine wave output consumer lines with also couple USB charging ports:
https://www.cyberpower.com/uk/en/product/series/Backup UPS Systems/PFC Sinewave
Naturally battery capacity is lower than in Eaton 5P, like can be deduced also from low weight.

With no actual manufacturer site that PowerCool sounds like some total cheap brand.
Also only 1200W for 2000VA advertising rating kinda tells that.


I have 3 UPS,cheap ones :D
on different pcs/components etc and never got any of the batteries to last longer than 3 years
How much you have black outs/how undersized those UPSes are?
Or maybe those just try to charge battery constantly or something like that.

In my previous UPS, MGE Pulsar Evolution which is predecessor of Eaton 5P it took 7 years until battery life started seriously collapsing.
 
Soldato
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Ive been browsing the ups today, the thing I don't get is, lets say, you want a 1200va ups, why does all the 1200va have different wattage?

Also my batteries are a 9Ah, could I run 10Ah, or would I blow it up.. Im just thinking 10Ah batteries would give me more runtime?..

This is now going badly off topic:D
 
Soldato
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Ive been browsing the ups today, the thing I don't get is, lets say, you want a 1200va ups, why does all the 1200va have different wattage?
It's the difference between 'real power' and 'apparent power'. From skim reading the thread I think it has already been explained.

The figure you need to worry about is the Watts. The better the UPS the closer the two figures are likely to be.

Higher Ah batteries will give a longer run-time. I can't see a problem unless you get silly with it. The charging side of the UPS has to be able to keep up.
 
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Ive been browsing the ups today, the thing I don't get is, lets say, you want a 1200va ups, why does all the 1200va have different wattage?
Forget volt amperes and look watt ratings.
It's watts which will define if your PC will overload UPS or not.
And those also define at what output level it is running during battery mode.
Active-PFC PSUs behave almost as pure resistive loads with near zero phase shift.
And also all better monitors or at least ones with possible higher power draw have active-PFC.
So there's zero need to take any reactive power into consideration.


If you want to go for engineering aspects here's something to get started.
Though best would be simply borrowing some basic electric engineering school book from library.
https://en.wikipedia.org/wiki/AC_power#Active,_reactive,_and_apparent_power
http://www.electronics-tutorials.ws/category/accircuits

Batteries come in standardized physical sizes so you can't just swap arbitrary battery into UPS.
Because as rule they're different for different capacities and voltages.
 
Soldato
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I have just done a test and at 150watt load, my ups wil last 10mins before it gets to low power of 25% and it should have lasted about 20 - 30mins. So the batts are coming to there end, but I am going to really try to get a new ups this time instead of replacing the batteries.

I might replace the batteries and use this ups on the tv and sky in our sitting room.
 
Soldato
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I have been on the net for hrs looking for a pure sine wave, about 1000watts for round about £150. I can only get them with "simulated sine wave" for that price and thats what my ups has...I wanted to upgrade to pure sine wave with half decent wattage, but Im looking at over £200?

That ups I found for just over £150 a few posts up,, well its too good to be true as there's no powercool website, so its a tad risky to buy it

:mad::mad:
 
Soldato
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I'd expect you to be looking at a lot more than £200 for a UPS like that.

The batteries alone for a 1500VA UPS are going to consume most of your £150 budget. They're either going to be significantly larger than the batteries you've had so far, or there's going to more of them. Don't forget that you'll be hit with that cost again every time the batteries need replacing.

Why are you running a UPS in the first place?

Why true sine? Is this just the usual spec creep we can all suffer from?
 
Soldato
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How much you have black outs/how undersized those UPSes are?
Or maybe those just try to charge battery constantly or something like that.
Well my ADSL connection is pants and every reset of the router was giving a speed decrease
and at the time,all those years ago i was burning a few DVDs and as you know you get a coaster if power is interrupted :)
 
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