Dell PowerEdge R200 Guide De Mise En Route page 11

Connecting the Power
Connect the system's power cable(s) to the system. Attach the cable
retention clip to the back of the system, run the cable through the cable
retention clip as shown, and close the clip.
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).
9
Getting Started Guide