Yes, it goes on-battery around once a year; it's plugged into a wall outlet that is fed by a building-wide UPS which fails once in awhile. I generally turn off my equipment when this happens - the computer isn't very useful when the building UPS is down, because there's no Internet - so the battery is never drained all that much.
Don't do what I did and get a set that will run all day but are too heavy to carry out of your office
Get this. http://www.apc.com/products/resourc...?base_sku=SMT1500&tab=features&total_watts=50 Check the load curve. That model works well on my mac pro with dual Apple 23inch displays I have a second one that keeps the cisco stuff running s o everything is good until the backup generator kicks in. A must have if you live in south florida
If you want guaranteed operation and an up time of potentially an entire day (or more), you really want to consider something like this. http://www.indoorgenerator.com/ One of these could power your entire office, a fridge and then some for probably less then what you would pay for a decent APC system. Living in Florida during summer storm season this product has already paid for itself. I've lived in the North East before and wouldn't consider anything else especially when outages occur due to ice storms.