Setup Guide

Power supplies
The S4048–ON ships with one AC power supply. Dell EMC recommends purchasing a second power supply.
The S4048–ON supports AC power supplies with two air-ow 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 eld replaceable. When running with full redundancy—two power supplies installed and running, you can remove and replace
one PSU without disrupting trac.
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 S4048–ON 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 qualied 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 S4048–ON.
• AC power supply with integrated fan
• AC power supply with integrated reverse ow 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. S4048–ON power supply units (PSUs)
1 PSU 1
2 PSU 2
6
Power supplies 25