28 Two-Post Rack Installation• System rack kits are intended to be installed in a rack by trained service technicians. If you install thekit in any other rack, be sure that the rack meets the specifications of a Dell rack.CAUTION: Do not move racks by yourself. Due to the height and weight of the rack, a minimum of two peopleshould accomplish this task.• Always load the rack from the bottom up, and load the heaviest item in the rack first.• Make sure that the rack is level and stable before extending a component from the rack.• Use caution when pressing the component rail release latches and sliding a component into or outof a rack; the slide rails can pinch your fingers.• Do not overload the AC supply branch circuit that provides power to the rack. The total rack loadshould not exceed 80 percent of the branch circuit rating.• Ensure that proper airflow is provided to components in the rack.• Do not step on or stand on any component when servicing other components in a rack.Before You BeginBefore you begin installing your system in the rack, carefully read "Safety Instructions," found earlier inthis guide, as well as the safety instructions found in your Product Information Guide for additionalinformation.CAUTION: When installing multiple systems in a rack, complete all of the procedures for the current systembefore attempting to install the next system.NOTE: For instructions on installing the system itself, see ""Installing the System in the Rack" on page 37."Important Safety InformationObserve the safety precautions in the following subsections when installing your system in the rack.CAUTION: You must strictly follow the procedures in this document to protect yourself as well as others whomay be involved. Your system may be very large and heavy and proper preparation and planning are importantto prevent injury to yourself and to others. This precaution becomes increasingly important when systems areinstalled high up in the rack.CAUTION: Do not install rack kit components designed for another system. Use only the rack kit for your system.Using the rack kit for another system may result in damage to the system and personal injury to yourself and toothers.Recommended Tools and Supplies• #2 Phillips screwdriver• 3/8-inch wrench or nut driver (if changing bracket to flush-mount configuration)• Masking tape or felt-tip pen to mark the mounting holes