How Do I determine what UPS I need?

HAL_404

[H]ard|Gawd
Joined
Dec 16, 2018
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I live in a semi-rural area and on occasion the lights flicker briefly and usually my PC keeps chugging alone but sometimes it shuts down so I need a UPS that will keep my PC running for 1 minute or less as well as my Vizio 55" TV (rated @ 99W). The PC uses a 650W SeaSonic Focus PSU ...

what UPS VA rating do I need to buy? Which makes/models have a PFC friendly smooth sine wave output (or does this really not matter)?
 
what else are you going to plug into the UPS?

I have an APC 1300 (780 watts) powering my desk and gaming rig in my sig, pulls about 500 watts when I am gaming and 250 or so just idling.

everything on this desk is powered by the APC 1300 UPS (the sever next to my gaming box is on it's own APC 1200 UPS on the floor).
IMG_2739-desk-processed.jpg
 
99w TV

650w Seasonic assume 80% efficiency. so 650 x 1.2 = 780w draw

780 + 99 = 879w needed

60% is the standard rated load conversion factor from VA to watts.

the inverse of .6 (60%) is 1.66667

780w x 1.66667 = 1300VA

so you need a ups with a minimum of 1300VA capacity, I'd size it at about 1500 for safety on your potential maximum draw.

Disclaimer: I sized this for maximum load that your power supply can handle. You can get away with less but you will need to calculate your power draw by 1) adding up the individual components or 2) getting a meter and directly reading the watts drawn from the wall.
 
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thanks everyone, that's what I needed to learn (especially the 60% conversion)

APC BX1500M or if I can afford it ... APC BR1500MS 1500 VA Pure SineWave :)
 
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