I have a recent vintage APC 1500 Smart UPS. I can't figure out how to turn it off from the front panel. I have had three APC Smart UPS's prior to this one and they all had power off buttons on the front panel. This unit has a "UPS on/off key". Pressing the "UPS on/off key" turns the unit on. Pressing the "UPS on/off key" again does not turn it off. I googled the problem and somewhere I read that holding down the switch turned the unit off. Holding down the switch causes it to execute a self test and then turn itself back on. Not what I wanted. And yes, I have read the manual. Several times.