How does a PoE splitter differ from a PoE injector or PoE switch?

A PoE (Power over Ethernet) splitter, PoE injector, and PoE switch all serve to deliver both power and data over Ethernet cables, but they do so in different ways, and each device is designed for specific needs in network setups. Here's a detailed breakdown of each:

1. PoE Splitter

A PoE splitter is a device that separates the power and data carried by an Ethernet cable that is already providing both. It is typically used in situations where you have a device (like an IP camera, VoIP phone, or another non-PoE device) that requires both power and data but the device itself doesn’t support PoE.

--- Function: The PoE splitter takes an incoming PoE signal (from a PoE-enabled switch or injector) and "splits" the power and data, providing separate output connections for each. This allows a non-PoE device to use both power and data over a single Ethernet cable.

--- Power Output: Typically, PoE splitters provide 5V, 9V, or 12V DC power outputs, depending on the splitter and the required input for the device being powered.

--- Use Case: Ideal for converting non-PoE devices (like old IP cameras or networked devices) to run on PoE infrastructure.

2. PoE Injector

A PoE injector is a device that adds power to an Ethernet cable for devices that require both data and power but are not connected to a PoE-enabled switch. It is essentially a "middleman" between a non-PoE switch or router and a PoE-enabled device.

--- Function: The PoE injector takes a regular Ethernet data cable and injects power into the cable, allowing the connected device (such as a PoE-powered IP camera, VoIP phone, or access point) to receive both power and data over the same cable.

--- Power Output: PoE injectors can deliver power in different standards, such as IEEE 802.3af (up to 15.4W) or IEEE 802.3at (PoE+, up to 25.5W) depending on the injector's capabilities.

--- Use Case: Perfect for situations where the network infrastructure lacks PoE capability but you need to deliver both data and power to devices.

3. PoE Switch

A PoE switch is a network switch that has built-in PoE functionality, meaning it can provide both network connectivity (data) and power to PoE-enabled devices over Ethernet cables. PoE switches are more integrated than injectors because they replace a standard switch and injector with a single unit that handles both tasks.

--- Function: A PoE switch connects multiple networked devices and simultaneously provides power to them via PoE on each port. It is the most efficient way to deploy a network of PoE devices because it eliminates the need for separate injectors.

--- Power Output: PoE switches can support multiple ports with varying power delivery based on the model. The power output can be up to IEEE 802.3af (15.4W per port), IEEE 802.3at (PoE+, 25.5W per port), or even IEEE 802.3bt (PoE++ up to 60W or 100W per port).

--- Use Case: Ideal for setups where you have multiple PoE devices, such as IP cameras, wireless access points, and phones, and want to manage them all through a central switch.

Key Differences

--- PoE Splitter: Splits power and data for non-PoE devices. Works with existing PoE cables.

--- PoE Injector: Adds power to a non-PoE Ethernet cable to provide power to PoE devices.

--- PoE Switch: A fully integrated network switch with the capability to provide power and data to multiple devices simultaneously over Ethernet.

In summary:

--- Use a PoE splitter when you need to power a non-PoE device using a PoE cable.

--- Use a PoE injector to add power to a non-PoE Ethernet cable for a PoE device.

--- Use a PoE switch when you want to connect multiple PoE devices and provide power and data from a single unit.