Setup Guide

Table Of Contents
Power supplies
The S4048ON ships with one AC power supply. Dell EMC recommends purchasing a second power supply.
The S4048ON supports AC power supplies with two air-flow directions, normal and reverse. Normal is from the I/O-side to the
PSU-side. Reverse is from the PSU-side to the I/O-side. Two PSUs are required for full redundancy, but the switch can operate
with a single PSU.
The PSUs are field replaceable. When running with full redundancytwo power supplies installed and running, you can remove
and replace one PSU without disrupting traffic.
NOTE: If you use a single PSU, install a blank plate in the other PSU slot. Dell EMC recommends using power supply 2
(PSU2) as the blank plate slot.
NOTE: ESD damage can occur if components are mishandled. Always wear an ESD-preventive wrist or heel ground strap
when handling the S4048ON and its components.
CAUTION: To prevent electrical shock, ensure that the S4048-ON is grounded properly. If you do not ground
your equipment correctly, excessive emissions may result. Use a qualified electrician to ensure that the power
cables meet your local electrical requirements.
Topics:
Components
AC power supply installation
DC power supply installation
Components
The following power supply options are available for the S4048ON.
AC power supply with integrated fan
AC power supply with integrated reverse flow fan
Power supply 1 (PSU1) is on the left side of the chassis; power supply 2 (PSU2) is on the right side of the chassis.
Figure 12. S4048ON power supply units (PSUs)
1. PSU 1
2. PSU 2
The PSUs have an integrated fan, which you cannot replace individually; if the fans integrated in a PSU fails, you must replace
the entire PSU. You can replace the fan trays individually. For fan tray replacement procedures, refer to Fans.
WARNING:
Prevent exposure and contact with hazardous voltages. Do not attempt to operate this switch with
the safety cover removed.
6
24 Power supplies