PoE operation

Using the commands described in this chapter, you can:
  • Enable or disable PoE operation on individual ports.

  • Monitor PoE status and performance per module.

  • Configure a non-default power threshold for SNMP and Event Log reporting of PoE consumption on either all PoE ports on the switch or on all PoE ports in one or more PoE modules.

  • Specify the port priority you want to use for provisioning PoE power in the event that the PoE resources become oversubscribed.

Power-sourcing equipment (PSE) detects the power needed by a powered device (PD) before supplying that power, a detection phase referred to as "searching." If the PSE cannot supply the required amount of power, it does not supply any power. For PoE using a Type 1 device, a PSE will not supply any power to a PD unless the PSE has at least 17 watts available. For example, if a PSE has a maximum available power of 382 watts and is already supplying 378 watts, and is then connected to a PD requiring 10 watts, the PSE will not supply power to the PD.

For PoE+ using Type 2 devices, the PSE must have at least 33 watts available. A slot in a zl chassis can provide a maximum of 370 watts of PoE/PoE+ power to a module.