Ray Wang Announces a Sleeker, Slimmer, Single-Board Espressif ESP8266-Powered OpenSprinkler v3.4

Computer scientist and maker Ray Wang has announced a new release of the Espressif ESP8266-powered OpenSprinkler smart watering system — simplifying the AC-powered board's design down to a single combined PCB and creating a more compact enclosure.

"While it retains the same familiar circuit as the current v3.3, version 3.4 features a completely redesigned enclosure for a refreshing new look," Wang explains of the new release. "The most significant update in version 3.4 is the shift from a two-layer circuit design — consisting of a top logic board and a bottom driver board — to a streamlined single-layer layout. Originally, the two-layer design in OpenSprinkler v3 was introduced to support interchangeable driver boards (AC-powered, DC-powered, and Latch), allowing the same logic board to interface with various solenoid types. While this approach offered flexibility, it also made assembly more complex and time-consuming. In version 3.4, we've consolidated the design into a single board, significantly simplifying assembly and improving overall efficiency."

The shift to a more compact and easier-to-make design isn't the only change in the new release of the AC-powered OpenSprinkler variant, though. Version 3.4 also includes a move to a barrel-jack connector for power in order to simplify wiring, the inclusion of two new sensor ports, and the introduction of an external connector for the device's optional wired Ethernet module. "Previously, the Ethernet connector was located on the internal circuit board, requiring users to open the enclosure, plug in the cable inside, and route it through a small opening — a process that was quite cumbersome," Wang explains.

"You see, when OpenSprinkler v3.0 was first introduced, I didn't plan to have wired Ethernet as [the Espressif] ESP8266 already provided built-in Wi-Fi. But in response to strong user demand, I improvised a solution by adding an internal connector and repurposed an opening — originally intended for a now-removed RF [radio-frequency] receiver — to route the cable outside. While the workaround was functional, it was far from ideal. With version 3.4, the enclosure finally includes a dedicated external connector, making Ethernet installation simple and user-friendly."

More information is available on Wang's blog, while the OpenSprinkler AC v3.4 is up for pre-order on the OpenSprinkler store at $150 excluding power supply and optional Ethernet adapter. The DC and Latch variants of the device will receive a v3.4 refresh by August, Wang says.