Quick Getting Started
Power over Ethernet Considerations
Cisco 350, 350X and 550X Series Managed Switches, Firmware Release 2.4, ver 0.4 15
1
 
NOTE 60-Watt PoE extends the IEEE Power of Ethernet Plus standard to double the power per port to 
60 Watts.
CAUTION Consider the following when connecting switches capable of supplying PoE:
The PoE models of the switches are PSE (Power Sourcing Equipment) that are capable of 
supplying DC power to attaching PD (Powered Devices). These devices include VoIP phones, 
IP cameras, and wireless access points. The PoE switches can detect and supply power to pre-
standard legacy PoE Powered Devices. Due to the support of legacy PoE, it is possible that a 
PoE switch acting as a PSE may mistakenly detect and supply power to an attaching PSE, 
including other PoE switches, as a legacy PD. 
Even though PoE switches are PSE, and as such should be powered by AC, they could be 
powered up as a legacy PD by another PSE due to false detection. When this happens, the PoE 
switch may not operate properly and may not be able to properly supply power to its attaching 
PDs. 
To prevent false detection, you should disable PoE on the ports on the PoE switches that are 
used to connect to PSEs. You should also first power up a PSE device before connecting it to a 
PoE switch. When a device is being falsely detected as a PD, you should disconnect the device 
from the PoE port and power recycle the device with AC power before reconnecting its PoE 
ports.
SG550X-48P SG550X-48P 48-
Port Gigabit PoE 
Stackable 
Managed Switch
N/A 7* PD69208 
(0x4AC2) /
7*69208M
 
(0x4B42) 
N/A af/at/60w
SG550X-48MP SG550X-48MP 
48-Port Gigabit 
PoE Stackable 
Managed Switch
N/A 7* PD69208 
(0x4AC2) /
7*69208M
 
(0x4B42) 
N/A af/at/60w
Table 1 Switches with Power Over Ethernet (Continued)
SKU Name Description PoE PD Chipset 
Type
PoE PSE Chipset 
Type
PoE PD AF/
AT/60W
PoE PSE AF/AT/
60W