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Beemer
24-09-2008, 01:37 PM
While chatting to a guy yesterday who knew a mutual friend we got onto the subject of power cuts in rural areas. I said unfortunately we have a lot of very brief power cuts where the supply is interrupted for a few seconds then comes back on again. The PC turns off and also the clocks and microwave, but the video and stove are fine unless the power is off for more than 30 minutes or so. He said he uses a UPS inline 2.2kw inverter and demonstrated how the PC carried on running when the power was turned off.

Now he was an electrical engineer by trade and I'm a real novice when it comes to things like this, so I'd like some advice before I rush out and buy one! I realise it's not something that will cover me for days on end when the power goes off (we lost it for six days recently), but it would be very handy to stop the PC shutting down when the power supply is interrupted briefly, or to allow me to save what I was working on before shutting down.

This guy said they were only about $200 and could be purchased from places like Ideal Electrical. What I'd like to know is, are they worth it for what I want? What do I need to know about them - how they work, what I need to do to set one up after purchase, etc. He said a 2.2kw one would be more than enough for the one PC I have - correct?

I thought it sounded like a great idea, but I don't want to buy one and then find it was a waste of money. I currently have surge protector devices on my PC but of course they do nothing to stop power being interrupted.

Thebananamonkey
24-09-2008, 02:12 PM
Sounds like a great idea. If you can find a 2.2kw one for ~ $200 I'd go for it.

It's basically like having a large battery attached to your computer. When you have reliable mains power it just sits there, but it picks up the slack when you don't. Gives you about 30min to back stuff up and shut down.

2.2 kW is heaps. Very few computers use much more than about 500W under normal load, so you've got quadruple redundancy if you can find one.

tweak'e
24-09-2008, 02:18 PM
2.2kw... i don't think so. massive overkill, that would power a whole room full of pc's and probably cost thousands.
$200 is more like a 600w which is enough for a basic pc.

however couple of catches. you need to make sure it is enough to run pc and monitor. CRTs take a lot of power to start up (need double the size UPS), LCD are a lot less. also things like printers, scanners, modems that you may need to use while power is off. these days with hungry PC's and big screens 800-1000w is more realistic.
also there the basic standby type which simply switch's over to battery when there is a power cut. or the more expencive interactive type which fully regulates power all the time. these are better if your in the sticks with iffy power (eg lights dim/brighten/flicker a lot of the time).

the other thing is replacement battery's. some makes/models use hard to get/expencive batteries which may need changing after 3-5 years.

edit: something like this http://www.ascent.co.nz/productspecification.aspx?ItemID=340611
and 2kw... http://www.ascent.co.nz/productspecification.aspx?ItemID=347720

nofam
24-09-2008, 02:20 PM
The other good thing about UPS's is that they filter your power as well; PC's are very susceptible to current fluctuations, so the UPS helps to clean up the power before it reaches the attached devices.

SolMiester
24-09-2008, 02:40 PM
The other good thing about UPS's is that they filter your power as well; PC's are very susceptible to current fluctuations, so the UPS helps to clean up the power before it reaches the attached devices.

You need a server class UPS for online filter....a $200 UPS will not be an online UPS.

I bought a 2000Kva about a month ago which is about 900w worth....$1200

tweak'e
24-09-2008, 04:08 PM
The other good thing about UPS's is that they filter your power as well; PC's are very susceptible to current fluctuations, so the UPS helps to clean up the power before it reaches the attached devices.

depends on what you call filter.

most use filters, but that doesn't clean up the power much. full online/interactive fully conditions the power. they are generally more expencive tho not necessarily server class.

hard thing here is working out the terminology as every manufacture calls it a different thing and its hard to work out the PR from the real tech.

Beemer
24-09-2008, 04:27 PM
He said he bought his years ago for $200 so they may well be far more than that now. I was surprised that something that did what it does was only $200. I have an LCD monitor and as I would mostly be using this to ensure the power supply is uninterrupted for short periods and to save any open work if the power did go off suddenly, how much would you suggest I go for if I get one? I have a 22" screen if that makes any difference.