9.1 PoE [T-Series Datasheet]

Power over Ethernet (PoE)

Power over Ethernet (PoE) is a technology that enables the transmission of both electrical power and data over a single standard Ethernet cable. This eliminates the need for separate power cables, simplifying installation and reducing cable clutter for compatible devices.

PoE Terminology

• PSE (Power Supplying Equipment): The device that provides power over the Ethernet cable (e.g.: PoE switches, routers, or injectors).

• PD (Powered Device): The device that receives power over the Ethernet cable (e.g. LabJack T8).

T-Series Device PoE Support

Some T-Series LabJack devices can operate as Powered Devices (PDs) using Power over Ethernet (PoE). Refer to the table below for specific PoE standard support for each device:

How PoE Works

For a PoE-enabled device (PD) to receive power, it must be connected to Power Supplying Equipment (PSE) via an Ethernet cable. The PSE, which can be a PoE-enabled network switch, router, or a standalone PoE injector, automatically detects the presence of a compatible PD. Once detected, the PSE will supply the appropriate amount of power to the PD.

PoE Standards (as of May 2025)

Currently, there are three primary PoE standards:

• PoE (IEEE 802.3af): The original standard.

• PoE+ (IEEE 802.3at): An enhanced standard capable of supplying more power than PoE.

• PoE++ (IEEE 802.3bt): The latest generation, offering the highest power delivery capabilities.

These newer PoE standards are backward compatible with older ones, ensuring that PoE+ PSE can power PoE PDs, and PoE++ PSE can power both PoE and PoE+ PDs.

Passive PoE

Passive PoE is not a standard and carries several risks. LabJack devices do not support Passive PoE.

Further Information

For more comprehensive details about Power over Ethernet, the Wikipedia page provides an excellent resource: https://en.wikipedia.org/wiki/Power_over_Ethernet