Preparing for installationAvaya CMS Dell R720 and R620 Computer Hardware Installation October 2015 13System precautions! WARNING:!WARNING: DO NOT make mechanical or electrical modifications to the computer. DellComputer Corp. is not responsible for regulatory compliance of modifiedcomputers.Ensure that the voltage and frequency of the power outlet used matches the electrical ratinglabels on the equipment.Wear antistatic wrist straps when handling any magnetic storage devices and printed circuitboards.Each power supply uses nominal input voltages of 100-240 V AC at 50-60 Hz. The computershould be powered by an Uninterruptible Power Supply (UPS) or a non-switched,dedicated, 20-amp circuit. Dell products are designed to work with single-phase power systemshaving a grounded neutral conductor. To reduce the risk of electrical shock, do not plug Dellproducts into another type of power source. Contact your facilities manager or qualifiedelectrician if you are unsure what type of power is supplied to your building.A UPS provides a temporary electrical supply to a computer for several minutes, depending onthe number of components connected to the UPS. For a CMS computer, a 1.5KVA minimum isrequired for each power supply. See your UPS documentation to determine the projectedamount of backup battery time for your model. If the system is without power for longer than thebackup time, the system may shut down improperly, and the customer could lose data.Each of the following items requires a separate power cord:● Computer● External peripherals● MonitorKeep in mind the following:● The room must have sufficient air conditioning capacity to support the cooling needs of theentire system.● The air conditioning system must have controls that prevent excessive temperature.