[USG Flex H] - Max wattage PoE budget

Hi @Maverick87 ,

Currently, for the USG FLEX H series, if the total PoE power consumption exceeds 30W, the system operates as follows:

• Scenario 1: When Port 3 and Port 4 are both supplying power (e.g., 13W + 13W), if a power spike during operation causes the total power to exceed 30W, the system will stop power delivery to Port 4 first to keep Port 3 running.
• Scenario 2: When one port is actively supplying power (e.g., 20W) and a newly plugged-in device on another port requests 15W, the system will maintain power to the active port and deny power to the new device to ensure the stability of the currently running equipment.

Regarding the feature to configure PoE port priority:

Unfortunately, this feature is currently not supported. Thank you for sharing your feature request with us. We have forwarded your feedback to our product team for future consideration. You can view and contribute to this idea at the following link:

Thank you for using Zyxel products and services.

Hi @Maverick87  ,

Just to clarify, if two PoE ports are actively supplying power and total consumption exceeds 30W, the system will prioritize keeping Port 3 powered rather than whichever device was plugged in first. Therefore, we recommend connecting your highest-priority device to Port 3.

The "first-plugged device takes priority" behavior in Scenario 2 only occurs when a newly connected device immediately requests power that would cause total consumption to exceed the power budget.

The reboot behavior of the USG FLEX H series is similar to "Scenario 1" (where both PoE ports are in use simultaneously): if the total power demand exceeds 30W after powering on, the system will suspend power delivery to Port 4 and prioritize power to Port 3.

However, exceptions may still occur depending on the characteristics of the powered devices (PDs). For example, after the USG FLEX H reboots, subtle timing differences in hardware detection and PD response between Port 3 and Port 4 can create a sequence variation. If the PD connected to Port 4 completes negotiation first and has the characteristic of immediately requesting high power upon connection (e.g., 25W), the USG FLEX H will allocate the power budget on a first-come, first-served basis.

We understand your requirements and have submitted the feature request regarding 'PoE port priority management' to our product team for future consideration.

Thank you for your feedback.

Please refer to the following FAQs:

[USG FLEX H] PoE Budget Specifications and Over-Budget Behavior