Hi: I've had this APC Matrix 5000 with 3 XR battery packs for almost 6 years now, and it's generally been rock solid, with lots of uptime when needed...the average laod is only around 24%, which probably helps. At around 1am last night, my network had a power event which brought everything down...everything came back up on its own except a customer's colo server, which has a dead power supply and one of my servers, which had a dead drive in its RAID 1 (the other was ok). I looked at the UPS menus...status, etc and everything looked 100%, with "BAD BATTS 0", 12 hours+ of est runtime, etc. I then decided to run a battery test, which I stupidly did without going into bypass mode first (kinda thought it would do that automatically), power was interrupted and the alarm started beeping with a "BAD BATT" light, after which power came back on and it eventually quieted down and looks the same as it did before...still "zero bad batteries" in the status menu, 100% etc. Any clues what the problem is here? Is it the UPS itself, or one of the battery packs? If the latter, is there a way to find out which one? TIA! James Smallacombe PlantageNet, Inc. CEO and Janitor up@3.am http://3.am =========================================================================