Dell PowerEdge R300 Guide De Mise En Route page 11

Connecting the Power
Connect the system's power cable(s) to the system (a redundant system is
shown in the illustration). For redundant systems, secure the cables with the
two Velcro straps that ship with your system, as shown. For non-redundant
systems, attach the power cord retention bracket that ships with your system.
Plug the other end of the cable into a grounded electrical outlet or a separate
power source such as an uninterrupted power supply (UPS) or a power
distribution unit (PDU).
Turning on the System
Turn on the system and monitor (optional).
9
Getting Started With Your System