HP Parallel Uninterruptible Power System - Manual (Page 17)

UPS installation 17
5. Insert screws through the mounting rail into the cage nuts or clip nuts.
6. Tighten the hex nuts.
IMPORTANT: If preparing the rails for integrated shipping, install the rear mounting brackets.
Installing the UPS
Before installing the UPS, review and observe all warnings in "Precautions (on page 13 )."
WARNING: A risk of personal injury or damage to the equipment exists. Uneven loading of
equipment in the rack might cause the rack to become unstable. Install the heavier components
first, and then continue to populate the rack from the bottom to the top.