This was originally posted on APC forums on 6/15/2010
Early this morning my APC Model BE500U started making a stuttering beeping sound. As I checked the unit I noticed the dreaded something electrical's burning smell. I hit the power switch and noticed the casing felt hot. The red LED Building Wiring Fault was not lit. I unplugged the unit from the wall and unplugged my printer, computer, monitor, and broadband modem from the unit. I then looked the unit over and noticed that the bottom of the unit about two inches from where the unit power cord enters the unit, had begun to melt. I've had this unit for awhile and never had a problem before. Did the battery cause the issue? Even though I didn't have any indication of a problem should I have replaced the battery at some point in time? When I find my camera USB cable I will post pictures.