Unsolved
This post is more than 5 years old
100 Posts
0
2298
Question about UPS
hello everyone
i need help here, since i can't find wattmeter tools anywhere near my city, so i don't know how much my PC taking power from outlet, i tried the watt simulator i find on a site, but i believe professional/expert in here could give me more detailed info/recommendation
i need UPS for my PC... here the detailed regarding my PC :
DELL XPS730
intel quad Q9550
Nvidia 9800GT
Asus Xonar D2X
4 WD HDD SATA (500+750+500+750)
2 DVD-combo drive (LG+Pioneer)
seems there 3 case fan
12colored Led
and Dell 1000w PSU
and what my PC equipment supplier option give me for the UPS is : APC BR1100CI-AS or APC BR1500i
also my supplier can make sure which one is better for me, so i hope people in here can help me
if possible i prefer to pic APC BR1100CI-AS since the price different is lots
APC BR1000i is $200 while APC BR1500i is $345
thanks alot before! ヽ(´ー`)ノ
Mike Gatehouse
14 Posts
0
June 10th, 2009 00:00
I've been pondering a similar dilemma. I had an exchange with an extremely helpful tech support guy at APC's UK site. As best I can understand it, this is what you need to consider:
1. The PSUs in most new PCs, including Dell, have circuits to implement PFC (power factor correction) as part of compliance with Energy Star 4.0.
2. Power supplies with PFC can draw up to 1.25 times their nominal wattage rating during initial inrush. This can occur when the PC is first turned on, and also when mains current fails and any attached UPS switches to battery power. So, if you have a PSU rated at, say 470 Watts, you need a UPS able to deliver at least 587.5 Watts. This is true despite the fact that most PCs in normal operation draw a much lower wattage than the PSU rating.
3. PSUs with PFC are more sensitive than older models to the wave-form delivered by a UPS. So, they dislike the step-approximated sine wave of older/cheaper UPS models, including APC's Back-UPS series. Because of this, the UPS will try to use the battery constantly to make up for the problem. Which will make the UPS, in the long run, acquire several problems, like battery life time being shortened quicker than the 3-5 years.
4. APC's Smart-UPS series (models with an SUA-prefix) deliver pure sine wave output, which is what you require.
So: you need to find out the PSU wattage rating of your Dell XPS730 (1000W) multiply by 1.25 (1,250W) and buy an APC Smart-UPS or similar from another manufacturer that can deliver a pure sinewave output of the appropriate wattage. N.B. (I'm sure you know this!) the wattage output is not the same thing as the VA rating, which is what is mostly quoted in UPS model numbers.
Hope this helps!