Anyone looking for UPS'

Juggy

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Can find a pretty good bargain here http://www.power4hour.co.za/index.php?

They're in Worcester and charge R10 000-00 for a 2000va device that is guaranteed to keep 4 PC's (more like 5 or 6), printer and a PABX running for 3 to 4 hours when the power goes out.
 

Gnome

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No offense but at that price I'd rather buy a APC double conversion online unit, actually even a APC line interactive unit for that price would be better.

R10 000 for square wave isn't on.
 

Juggy

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No offense but at that price I'd rather buy a APC double conversion online unit, actually even a APC line interactive unit for that price would be better.

R10 000 for square wave isn't on.

What about the uptime? I've used the APC rackmount kits and they only give around 30 minutes uptime.
 

Gnome

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What about the uptime? I've used the APC rackmount kits and they only give around 30 minutes uptime.

Buy the UPS for around R5k (for 2KW) and buy a bunch of 100Ah batteries at R1k each (four total) then you'll have about 2.4 hours uptime assuming 2KW of usage. And it's sine wave.

The only downside is you'll need to get your hands dirty by removing the battery tray and connecting the batteries you bought where the tray used to be connected.
 

Juggy

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Buy the UPS for around R5k (for 2KW) and buy a bunch of 100Ah batteries at R1k each (four total) then you'll have about 2.4 hours uptime assuming 2KW of usage. And it's sine wave.

The only downside is you'll need to get your hands dirty by removing the battery tray and connecting the batteries you bought where the tray used to be connected.

Is there a massive difference in performance wrt waves? I don't have an indepth understanding of it and am interested in case I'm following the wrong path.

This is giving me 3 to 4 hours.
 

kayvee

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So called "modified sinewave" are in fact square wave output, and a lot of sensitive equipment, including anything with a mains driven motor don't like it at all. Some TV's and audio equipment also don't like it, but most modern switch-mode supplies don't seem to mind. Sticking to a true sine wave inverter is best, but they are more expensive.
 

Gnome

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Is there a massive difference in performance wrt waves? I don't have an indepth understanding of it and am interested in case I'm following the wrong path.

This is giving me 3 to 4 hours.

For a pic of how they look check here: http://en.wikipedia.org/wiki/Image:Waveforms.svg

Basically AC power coming from the mains is sine wave (supposed to be at least ;) ) and certain appliances might not perform as they should if they don't run from sine waves (motors being a prime example) but if you're running only switch mode power supplies (those used by computers) then square wave is perfectly fine.

But generally a UPS that provides sine wave is substantially more expensive and of better quality (there are exceptions I'm sure).

The only thing about modifying a UPS is that you have to have a basic understanding of how a DC circuit works so you can identify if the batteries are connected in parallel or series. A multimeter I would say is a must also, just to double check (you get ones for around R40)

I think generally a UPS has a certain standard of quality while inverters are pretty much the wild west, which is why if the inverter doesn't have a seriously improved price I wouldn't risk it, of course that is entirely my opinion.
 

killadoob

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im just thinking they may be pushing it a bit claiming they can run that stuff for 4 hours

im also asking if they will give your money back should that stuff run for less than they say it will?
 

Juggy

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im just thinking they may be pushing it a bit claiming they can run that stuff for 4 hours

im also asking if they will give your money back should that stuff run for less than they say it will?

The reason I say "what" is because I have 3 PC's, 1 server, ADSL wireless router and a 48 port GB switch running on the 1000va version for 3 hours.
 

Juggy

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Surely it depends more on the battery capacity when it comes to the length of time? The KVA rating is purely power output not ammount of time it will last.
 

killadoob

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yea i think this is where im getting confused juggy :)

cause a normal usp you buy at a pc show which is lets say a 2000 wont run all that stuff for more than 30 minutes :)

sounds really tempting though
 

Juggy

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yea i think this is where im getting confused juggy :)

cause a normal usp you buy at a pc show which is lets say a 2000 wont run all that stuff for more than 30 minutes :)

sounds really tempting though

The 2000va version weighs 55kg's and the 1000va version weighs 35kg's.

You also get each config in 3-4 hour uptime and 7-8 hour uptime.

Nasty big buggers.
 

killadoob

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holy cow

those are not the same as the ones i know about

omfs thats insane
 

Juggy

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Not too bad then, the 1000va battery pack is about the size of a large home entertainment systems subwoofer.
 
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