Extreme Networks BlackDiamond 8800 Series - Active Internal PSU with Single 600-LS Module Failure; Dual 600-LS Module Configuration: Full Power; External to Internal PSU Transfer; Inactive Internal PSU with a Dual EPS-600 LS Configuration and Module Failure

EPS-600LS External Power Module
Extreme Networks Consolidated ExtremeXOS Hardware Installation Guide
329
Dual 600-LS Module Configuration: Full Power
Two EPS-600LS power modules provide full power at 740 W, which is 15.4 W of PoE power to all 48
ports. In this full power configuration, the internal PSU 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. Should one of the EPS-600LS power
modules fail, the third power module continues to provide uninterrupted full PoE power. The internal
power supply is disabled in this configuration.
Internal-to-External PSU 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.
Internal PSU failure with single EPS-600LS module. When an EPS-C with a single EPS-600LS is connected
to the Summit X450e-48p or X250e-48p switch and the internal PSU fails, power is drawn from the EPS-
600LS without power interruption to the PoE connected devices.
Two or Three EPS-600LS modules. When the Summit X450e-48p or X250e-48p switch detects that an EPS-
C is connected and providing stable power from two or three EPS-600LS power modules, the PoE
power budget is automatically recalculated to enable 740 W of PoE power. The internal PSU is disabled
to prevent damage from excessive current demands beyond the internal PSU's capabilities.
External to Internal PSU Transfer
This section describes the conditions where power from an external power module either fails or is
disconnected.
Active Internal PSU with single 600-LS module failure. When an EPS-C configured with a single EPS-
600LS module is connected to the Summit X450e-48p or X250e-48p switch and the EPS-600LS fails or is
disconnected, power is drawn from the internal PSU without power interruption to the PoE connected
devices.
Inactive Internal PSU with a dual EPS-600LS configuration and module failure. The following paragraphs
describe the PoE behavior when an EPS-C configured with two EPS-600LS modules is connected to the
Summit X450e-48p or X250e-48p switch and one or both EPS-600LS modules fail or are disconnected.
It is possible for one external power module to fail while the second power module continues to
function. If one EPS-600LS fails, the PoE power budget is automatically reduced to 370 W for the
Summit X450e-48p or X250e-48p switch. PoE port power management occurs as described in the
ExtremeXOS 12.0 Concepts Guide, Power over Ethernet section. With only a single operating power
module, the remaining EPS-600LS behaves as a redundant power module. The internal PSU is returned
to an active state to provide redundant capability.
If both external power modules fail or are disconnected, PoE power is interrupted while transferring
PoE power back to the internal PSU. The internal PSU is then limited to 370 W of PoE power. The PoE