How much amperage is my system pulling?

I'm not sure on the amperage (Volts * Amps = Watts, so Watts / Volts = Amps), but the best recommendation I can give it to make sure you connect your CRT monitor and printer to Surge Protection of your UPS instead of Battery Backup.

CRT's pull lots of electricity (especially a 19"), and they can drain your UPS battery faster than your computer will by itself. Just make sure you learn the keyboard shortcuts for things like saving (usually Ctrl+S), switching between programs (Alt+Tab) so you can save everything, and shutting down the system (Ctrl+Esc, U, U for XP).

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Okay, you're concerned about blowing your breakers. Unfortunately, now you have to take into account the difference in voltages between your AC (usually 115VAC) circuit and your DC (+3.3VDC, +/-5VDC, and +/-12VDC) computer and various AC or DC peripherals.

Keep in mind, when you lower the voltage, you increase the current (amperage) for the same wattage.

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It is very hard to really say, I would estimate roughly 100-115 amps. Voltage times amperage equals wattage. You can buy devices at radio shack, lowes, or home depot that will read all of that data for you

Less than 20 amps, but hard to pin point.

Check out the link below-fill out the form and it will tell you how many watts you need.Then devide by 120Volts.

You should have Power Chute with the APC...install that software and it will tell you.