Installation Guide

The following table summarizes the PoE power behavior for the Summit X450e-48p or X250e-48p
switch based on the number of power modules in use.
Table 75: PoE Power Behavior
Internal
Power Supply
Status
EPS-600LS (1x) EPS-600LS (2x) EPS-600LS (3x) External Power
Supply/Chassis
Failed/Disconnected
Internal
Power
Supply:
Power On
370 W of
redundant power
740 W of
external power only
Internal power
supply disabled
740 W of
external power only
with 2 + 1
redundancy
Internal power
supply disabled
370 W of
internal power only
Internal
Power
Supply:
Power Failure
370 W of
external power
only
740 W of
external power only
740 W of
external power only
with 2 + 1
redundancy
No PoE power
Single 600-LS Module Configuration: Redundant PoE Power
A single EPS-600LS power module provides redundant PoE power capability with the same 370-watt
capacity as the internal power supply.
The internal Summit X450e-48p or X250e-48p power supply is capable of 370 W of PoE power: 15.4 W
supplied to each port for a 24-port configuration and 7.7 W supplied to each port for a 48-port
configuration.
• If the internal power supply fails, the external power module will provide power to PoE devices at the
same power levels as the internal power supply without any power interruptions.
• If the EPS-600LS power module fails or is removed, the internal power supply continues to provide
PoE power without any power interruptions.
Dual 600-LS Module
Configuration: Full Power
Two EPS-600LS power modules provide full power at 740 W; this power level allows 15.4 watts of PoE
power to all 48 ports.
In this full-power configuration, the internal power supply is disabled, and therefore redundant power is
not available.
Triple 600-LS Module Configuration: Full Redundant Power
Three EPS-600LS power modules provide the full 740 W of power for 15.4 W of PoE power to all 48
ports.
In addition, this configuration provides 2:1 redundancy. If one of the EPS-600LS power modules fails, the
third power module continues to provide uninterrupted full PoE power. The internal power supply is
disabled in this configuration.
Internal-to-External Power Supply Transfer
This section describes the conditions that would cause the Summit X450e-48p or X250e-48p switch to
draw power from the external power unit.
X450 and X250 PoE Redundant Power
Configurations Power Supplies for Use with Your Switch
176 Summit Family Hardware Installation Guide