D-Link DGS-3000-28LP Quick Installation Manual page 5

Plug the AC power cord into the power socket of the Switch.
Figure 6 — Connect the power cord to the Switch
Slide the retainer through the tie wrap until the end of the cord.
Figure 7 — Slide the Retainer through the Tie Wrap
Circle the tie of the retainer around the power cord and into the locker of the retainer.
Figure 8 — Circle around the power cord
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