User Guide

This article assists in troubleshooting common

Power over Ethernet (PoE) problems with

NETGEAR PoE switches.

Power over Ethernet (PoE) is a networking feature defined by the IEEE 802.3af and IEEE

802.3at standards. PoE lets Ethernet cables supply power to network devices over the existing

data connection.

PoE-capable devices can be power-sourcing equipment (PSE), powered devices (PDs), or

sometimes both. The device that transmits power is a PSE, while the device that is powered is a

PD. Here, the PSE is a PoE switch. The PDs may be devices such as VoIP phones, wireless

access points, and IP cameras.

For further information on PoE, refer to https://kb.netgear.com/209/What-is-PoE-Power-over-

Ethernet

Follow the guidelines in this article to help resolve problems such as:

 PD is not powering on.

 PD is powering off intermittently.

 Certain PDs are powering on while other PDs on the same PoE switch remain powered

off.

PoE Standards

As mentioned above, PoE is defined by IEEE 802.3af (known as PoE) and 802.3at (known as

PoE+) standards. If your PoE switch supports IEEE 802.3at, it can supply power to both 802.3at

and 802.3af PDs. However, if your switch supports 802.3af only, it can only supply power to

802.3af (PoE) PDs.

PoE Budget

Your PoE switch has a PoE budget, that is, the total amount of power measured in watts that it

can supply to PDs at one time. Refer to the datasheet of your switch to verify its PoE budget.

You should ensure that the amount of power being drawn by your connected PDs does not

exceed the PoE budget of your switch. When calculating the amount of power being drawn by

your PDs, you need to check the PoE class to which the PD belongs. The PoE class of a PD

determines the amount of power it will require, as seen in the below table:

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This article assists in troubleshooting common Power over Ethernet (PoE) problems with NETGEAR PoE switches. Power over Ethernet (PoE) is a networking feature defined by the IEEE 802.3af and IEEE 802.3at standards. PoE lets Ethernet cables supply power to network devices over the existing data connection. PoE-capable devices can be power-sourcing equipment (PSE), powered devices (PDs), or sometimes both. The device that transmits power is a PSE, while the device that is powered is a PD.
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Range of Power Delivered to the Powered Device PoE/PoE+ 0.44W-12.95W PoE/PoE+ 0.44W-3.84W PoE/PoE+ 3.84W-6.49W PoE/PoE+ 6.49W-12.95W PoE+ 12.95W-25.5W Device Standard Class 0 1 2 3 4 Minimum Output at PoE Switch Port (Minimum Allocated) 15.4W 4.0W 7.0W 15.4W 30.0W Maximum Output at PoE Switch Port (Maximum Allocated) 16.2W 4.2W 7.4W 16.2W 31.6W If for example, you have 10 PDs that are class 2, the total budget required is 70W.
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make a configuration backup before completing this step. Note: This does not apply to unmanaged switches. Further Considerations   If your PoE switch model is GS105PE, then refer to https://kb.netgear.com/25541/GS105PE-PoE-troubleshooting for guidance specific to this device. If you see symptoms where you cannot power more than one PD in a set of adjacent ports, such as scenarios outlined below, please contact NETGEAR Support.