OpenSprinkler Use DC with Power over Ethernet (PoE)

Occasionally we encounter use cases where users Power-over-Ethernet (PoE) , which allows a single Ethernet cable to provide both network connectivity and power. This configuration eliminates the need for a separate power line, making it particularly useful in remote or hard-to-reach locations where running additional cables is challenging. To enable PoE, a PoE switch injects voltage—typically 48 VDC—into the Ethernet cable, which then transmits both data and power. A PoE-compatible circuit is required on the receiving end to regulate the voltage to a usable level, such as 12 VDC. OpenSprinkler does not support PoE natively because its Ethernet module and power supply do not comply with PoE standards. However, you can use a commercially available PoE splitter to separate power and data: The splitter outputs 12 VDC and a standard Ethernet signal (without 48 VDC). OpenSprinkler DC powered by 12 VDC, it is compatible with a PoE switch when used with a suitable splitter.

The image below shows a typical PoE splitter. One end has an Ethernet jack for connecting the PoE cable. The other end splits the signal into two outputs: a 12 VDC power connector and a standard Ethernet connector. The 12 VDC connector connects to the power connector of the OpenSprinkler DC while the Ethernet connector is plugged into the wired Ethernet module.

The following diagram illustrates the complete setup. With this configuration, a single Ethernet cable can provide both power (for the controller and the solenoid valves) and the data connection. We successfully tested this setup using a TP-Link 4-port PoE switch, a 12 VDC at 2 A PoE splitter, and a OpenSprinkler DC with a wired Ethernet module – it worked perfectly. Please note that this configuration only works with DC-powered OpenSprinklermodels (including OpenSprinkler Latch) as they can be operated directly with 12 VDC. It is not suitable for OpenSprinkler AC because there is no easy way to convert 12 VDC to the required 24 VAC.