The system makes use of a Raspberry Pi to regulate when every valve activates and for a way lengthy. It does this by way of a customized RS-485 valve grasp board, whose code and design recordsdata are on GitHub. The grasp board communicates with the Pi over I2C and points RS-485 instructions whereas controlling the 12V line to the valves. Toggling the 12V provide is a great transfer it lets [Vinnie] save energy by not conserving the valves energized when idle.
On the valves themselves lives a valve node board (additionally on the GitHub repo). Every node has a novel deal with so it is aware of when its identify known as to open or shut a valve. The valves are latching solenoids, very best as a result of they don’t require fixed present through the watering cycle. The Valve Nodes additionally assist their very own protocol to report state, firmware model, and permit in-situ configuration.
Make sure to head over to [Vinnie]’s undertaking web page and take a look at all of the work that went into this nice DIY irrigation management system, together with the considerate boards and instruments he made to assist others set it up. It is a welcome addition to the sprinkler-related tasks we’ve seen.
