Originally posted by: chuck2002
Somewhat unrelated, but I have been looking online and haven't found the answer yer....
With allt he hurricanes and power issues we are having in FL, I would like the UPS to switch to battery power without any beeps telling me it's on battery that always happen in the middle of the night and wake me up.
Anyone know how to tell it not to beep? I have a few smaller UPS models like the 300 and 500 series.
Thanks.
Yup - do what I did to mine. I got out the soldering iron, opened up the UPS, removed the circuit board, and took out the little cylindrical beeper. Not so much as a peep from it now.

Was kind of stupid of them to exclude any kind of silencing option. Oh well - I found a permanent solution.
Why isn't the output read as super-clean? That's what they always adverise these things as doing.
The output is a modified sine wave - it's not smooth like the sine wave power from the wall. It's a digital approximation, which is blocky.
Link. This is fine for things like computers, because their power supplies do so much adjusting to incoming power, that none of the effects of the SSW make it down to the hardware. However, when this power comes into a UPS, it puts a strain on the power filtering circuitry, and I think that increases the current draw, which can overload the first power supply.