Dell PowerEdge R415 Systems Guide De Mise En Route page 7

Installing the Power Cord Retention Bracket
Attach the power cord retention bracket on the right bend of the power
supply handle. Bend the system power cable into a loop as shown in the
illustration and attach to the bracket's cable clasp.
Plug the other end of the power cable(s) 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
Press the power button on the system and the monitor. The power indicators
should light.
5
Getting Started With Your System