Rockwell Automation 1783-BMxxx Stratix 5700 Ethernet Managed Switches User Manual - Manual (Page 85)

Rockwell Automation Publication 1783-UM004E-EN-P - June 2014 85
Switch Software Features Chapter 3
Power over Ethernet (PoE) Switches with PoE 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 switch 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 switches with Cisco end devices.
The powered Cisco end device notifies the switch of the amount of power
it is consuming. The switch can supply or remove power from the PoE
port.
• Support for Cisco intelligent power management. A powered Cisco end
device and the switch 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 switch.
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.