Where should the UPS be placed in the server rack?

There are weight and heat output issues to consider when rack mounting a UPS system and the best position is in the base or lower middle section of the server rack. At height in an otherwise empty server rack there is an issue of the rack becoming top-heavy. Heat also rises and the UPS system will output some heat internal to the server rack. It is also important to ensure the batteries are within a 20-25˚C ambient to prevent them being damaged by excessive heat; this will degrade their working life.