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Josh-D. S. Davis

Xaminmo / Omnimax / Max Omni / Mad Scientist / Midnight Shadow / Radiation Master

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Power Woes
Josh 2004 Happy
So, Khai's computer has been powering off.
Happened today when the printer turned on (always causes a UPS blip since it's on the same circuit with the kids' computers).

I pull the UPS, thinking maybe it's failing, but it SEEMS okay.

BUT, his UPS is a 375VA unit.
VA, what? Well, that's Peak RMS Volts times Amps.
It's like watts, but at the highest point, rather than sustained.

For a UPS, multiply by 0.6 to get peak wattage.
Over the peak wattage, you have zero battery life.
At 77% peak, you have only 2 minutes.
At 15% peak, you have 40-45 minutes.

So, when the printer turned on, the voltage drops (brown-out).
The UPS then kicks on, but was in overload condition.
In overload, the UPS turns off to prevent damage.

Max has a 450VA which seems to be okay, but it doesn't have a USB cord.
So, if we had a true power outage, his system couldn't shut itself down.

Both of their systems are the same. 375VA is overload, and that is 225 watts.
So let's say 99% of the time, they pull less than 250 watts.
So, 5 mins runtime should be about 410 Watts, or 680VA

I really would like longer runtimes, and better voltage regulation,
but the match for this load is already $70.
The better option is $85

I guess I could get the good one, and leave Max on the one without a USB connection until it's time to upgrade... Or swap them, since Max runs the minecraft server...