Rockwell Automation 1783-Mxxx Stratix 8000 and 8300 Ethernet Managed Switches User Manual - Manual (Page 61)

Rockwell Automation Publication 1783-UM003I-EN-P - March 2014 61
Switch Software Features Chapter 3
Power over Ethernet
(PoE) Ports PoE expansion module ports are software-configurable and provide these
features:
• Support for IEEE 802.3af (PoE)-compliant devices.
• Support for IEEE 802.3at Type 2 (PoE+), which increases the available
power that can be drawn by powered devices from 15.4…30 W per port.
• Automatic detection and power budgeting. The module maintains a
power budget, monitors and tracks requests for power, and grants power
only when it is available.
• Power to connected Cisco pre-standard and IEEE 802.3af-compliant
powered devices if the switch detects that there is no power on the circuit.
• Support for Cisco Discovery Protocol (CDP) with power consumption.
This features applies only when using PoE expansion modules with Cisco
end devices. The powered Cisco end device notifies the expansion module
of the amount of power it is consuming. The module can supply or remove
power from the PoE port.
• Support for Cisco intelligent power management. A powered Cisco end
device and the module negotiate through power-negotiation CDP
messages for an agreed power-consumption level. The negotiation allows a
high-powered device consuming more than 7 W to operate at its highest
power mode. The powered device first starts up in Low-power mode,
consumes less than 7 W, and negotiates to obtain enough power to operate
in High-power mode. The device changes to High-power mode only when
it receives confirmation from the expansion module.
Cisco intelligent power management is backward-compatible with CDP
with power consumption. The module responds according to the CDP
message that it receives. CDP is not supported on third-party powered
devices, so the module uses the IEEE classification to determine the power
usage of the device.