Why does my UPS 500 only last 15 min, yet my UPS 1400 last 6 hrs?!!?!

[JEDI]

I have an APC UPS 1400. I have a 17" LCD and a P3 1.1GHZ tower attached to it. Power went out during a storm, and I on UPS power for 3 hrs b4 the lights came back on, and the UPS still had 1/2 power left.

I just recently read the specs on the box on a APC UPS 500. It said 15 min for a 17" monitor and tower computer.

Based on a UPS 500, shouldn't a UPS 1400 only have ~40 min???

 

[NokiaDude]

The 1400 is a MEGA battery backup so expect a long backup running time. Plus the battery maybe a Nickel Hydride.

 

[mechBgon]

The VA rating indicates how much power the circuitry can deliver, not the runtime. You could chain ten batteries in parallel to the 500VA's power circuit, but it would still have a 500VA output capacity (but yes, it would have ten times the runtime).

Take an APC SmartUPS Pro 750XL, for instance. You can buy stack-on battery modules to boost the runtime to some pretty outrageous extents, but it's still a 750VA unit. Your 1400VA simply has a very large battery and given the same computer, it will run a long time.

 

[JEDI]

ahh..thought the rating (ie: 500/1400) was the amount of energy the battery can store.

does that mean with an ups 1400, i can run my 1000 watt heater

 

[mechBgon]

I would stick with APC's recommendations and not go beyond 950W: specs

 

[JEDI]

thx for the link

ups 1400 runtime: 5 hrs 24 mins at 50 watts (80 va)

my lcd AND tower only took up 50 watts even though i have a 300watt powersupply on the tower alone?

 

[arcas]

If it's a SmartUPS 1400 and you've set up the funky serial connection, you can query the UPS for things like how much power you're currently drawing, what its estimated remaining runtime is, etc. Obviously, the UPS has to have been calibrated for the numbers to be accurate.

I suspect your rig is actually pulling somewhere in the neighborhood of 100-150 watts. Your CPU alone is probably drawing 40 watts or more (don't recall what the P3-1.1ghz dissipation numbers are).

 

[zephyrprime]

The whole rating system they use for UPS's sucks. They should measure in Watts not VA. Who the hell knows what a VA is? People know what watts are or at least vaguely do based on their experience with light bulbs. And capacity should be measured in kilo joules.