Configuring the switch

If the new Class 5-8 PDs support LLDP power negotiation, the default switch configuration does not require additional CLI configuration changes. However, if the new .Class 5-8 PDs do not support LLDP or need the maximum PoE power at initial power up, then switch CLI config changes are required on a port basis to disable dot3Tlvs which provide Class 6 (60W) power delivery.

no lldp config <port> dot3TlvEnable poeplus_config

When DLC is enabled, a Class 4 and above PD can draw up to 15.4W power at the PSE side. Essentially a Class 4 or above PD is demoted to Class 3 to maintain the legacy functionality of switches where a PD can draw 15.4W at PLC. The PD must use LLDP to negotiate for higher power. For Dual Signature PD, each channel can draw up to 15.4W of power to ensure each port can draw a total of 30W.

• The default switch configuration always power demotes all Class 4-8 SS PDs to Class 3 power and requires successful LLDP dot3Tlv 29 octet power negotiation for Class 5-8 PDs or 12 octet power negotiation for Class 4 PDs before increasing the power delivery to above 16W.

• The default switch configuration always power demotes all Class 4 and above DS PDs to Class 3 power at PLC. It requires successful LLDP dot3Tlv 29 octet power negotiation through DLC.

• The switch requires the PD to negotiate through LLDP for any power request above 13W. In this case, the switch class demotes the PD to Class 3 power.

• The switch does not have enough available power in its reserve to supply the full power requested by the PD. In this case, the switch offers a lower Class level of power to the PD. For example, the switch offers Class 4 power (25.4 W) or class 3 power (13 W) to a Class 5 PD or a Class 6 PD.