Manually configuring PoE power levels

You can specify a power level (in watts) allocated for a port by using the value option. This is the maximum amount of power that will be delivered.

To configure a port by value:

Procedure
  1. Set the PoE allocation by entering the poe-allocate-by value command:
    switch(config) # int A6 poe-allocate-by value
  2. or in interface context:
    switch(eth-A6) # poe-allocate-by value
  3. Select a value:
    switch(config) # int A6 poe-value 15
  4. or in interface context:
    switch(eth-A6) # poe-value 15

To view the settings, enter the show power-over-ethernet command, shown in Figure 8: PoE allocation by value and the maximum power delivered.

Figure 8: PoE allocation by value and the maximum power delivered
switch(config)# show power-over-ethernet A6

 Status and Counters - Port Power Status for port A7

  Power Enable     : Yes
                                       LLDP Detect     : enabled
  Priority         : low               Configured Type :
  AllocateBy       : value             Value           : 15 W 
  Detection Status : Delivering        Power Class     : 2

  Over Current Cnt : 0                 MPS Absent Cnt  : 0
  Power Denied Cnt : 0                 Short Cnt       : 0

  Voltage          : 55.1 V            Current         : 154 mA
  Power            : 8.4 W
  • Maximum power delivered.

If you set the PoE maximum value to less than what the PD requires, a fault occurs, as shown in Figure 9: PoE power value set too low for the PD.

Figure 9: PoE power value set too low for the PD
switch(config)# int A7 poe-value 4

switch(config)# show power-over-ethernet A7

 Status and Counters - Port Power Status for port A7

  Power Enable     : Yes
                                       LLDP Detect     : enabled
  Priority         : low               Configured Type :
  AllocateBy       : value             Value           : 4 W
  Detection Status : fault             Power Class     : 2

  Over Current Cnt : 1                 MPS Absent Cnt  : 0
  Power Denied Cnt : 2                 Short Cnt       : 0

  Voltage          : 55.1 V            Current         : 154 mA
  Power            : 8.4 W
  • ‘Fault’ appears when the PoE power value is set too low.