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What should I do if the PoE switch does not supply power?

There are many power supply methods for switches, including centralized power supply, independent power supply, 220V AC power supply, and PoE power supply. With the use of different occasions, especially PoE switches are used a lot, but there are also many problems. One of the more common ones is that the power supply of the PoE switch suddenly does not supply power. What should I do at this time?

1. When the PD (such as AP, camera, IP phone, etc.) fails to work abnormally, first confirm whether the power supply is abnormal through the working indicator of the PD and the log of the switch.

When the working indicator of the PD is always on, it means that the PD is charged. If there is no record of PoE power-off in the log of the switch, it means that the PD is not powered off. This kind of problem may be the problem of port negotiation or AC management.

2. Confirm environmental factors, such as whether the network cable is faulty or the grounding is poor.

During the PoE power-on stage, the connected PDs need to be detected and classified. If there is external interference, the judgment of the detection and classification may be affected, and the PDs cannot be powered on. Please ground the PoE switch reliably.

  1. Confirm whether the switch and power module support the PoE function and whether the power is sufficient.
  2. Collect the on-site information of the faulty device and PD, and also need to know the specific model, power, and supported standards (802.3af/802.3at) of the connected PD.

5. Determine whether the connected PD is a standard PD. If it is a non-standard PD, after confirming that the power supply is 48V, you can try the following methods:

A, PoE force-power (enable forced power supply)

B, PoE legacy enable (power on non-standard devices)

C, PoE high-inrush enable (turn on anti-high current surge)

D, If it cannot supply power, please collect it in diagnostic mode: display PoE chips

6. Confirm whether only some modules of PD cannot supply power:

If it is confirmed that only some of the module functions are unavailable, after enabling LLDP, run the following commands to plug and unplug the network cable, or re-enable and re-enable the PoE function verification:

[Quidway-Ethernet0/0/3]lldp dot3-tlvpower 802.3at

[Quidway-Ethernet0/0/3]undo lldptlv-enable med-tlv power-over-ethernet