Three short stories from a real PHOA deployment: how a Node gets its power without a new outlet, how the enclosure mounts on the property, and the off-the-shelf box it all lives in. None of this requires an electrician, a service truck, or downtime on the irrigation controller.
1 · Tapping 5VDC from the irrigation controller's 24VAC
A residential irrigation controller already has the two things a Node needs: weatherproof housing on an outside wall, and a permanent 24 VAC supply for its solenoid valves. We piggyback on both. A small AC→DC buck module rectifies a tap off the 24 VAC bus to a clean 5 V, which feeds the Node sitting a few feet away. No new conduit, no new outlet, and the irrigation controller keeps working untouched.
Total parts added inside the controller: one buck module and four short wires. Five-minute job.
Frame 1 · The starting pointAn existing Rain Bird ESP-4 outdoor controller, the kind that's already wired to the irrigation valves on most properties. Closed up and weatherproofed. Nothing about it changes as far as the homeowner is concerned.Frame 2 · Open the outer lidThe user-facing programming panel: dial, buttons, schedule readout. This is where the homeowner sets watering days and times. The 24 VAC supply and valve outputs are behind this panel, accessible by swinging the face out.Frame 3 · Inside the wiring compartmentThe terminal strip across the top is where the 24 VAC transformer and the valve wires land. A small green buck-converter PCB sits in the lower-left corner; the orange wire is the new tap off the 24 VAC terminal, the black/red pair leaving the box carries the regulated 5 VDC to the Node.Frame 4 · The tap, up closeThe module is an adjustable AC→DC buck regulator. Trimmed to 5.0 V output, current draw < 100 mA. The orange tap takes 24 VAC off the controller's input terminal; output goes through the existing cable gland out to the Node.
2 · Mounting the Node on the property
The Node enclosure is small enough to disappear under a deck, on a fence post, or on the back of a garage, anywhere it has line-of-sight to the water meters and a power feed from the controller a few feet away. The photos below show one real install, going from wide property context down to the box itself.
Frame 1 · Property contextThe Node lives on the outside wall of a side yard, low to the ground, on a south-facing cedar wall. Easy to find for service, invisible to the casual visitor. The 5 VDC cable runs a few feet to the irrigation-controller box just out of frame.Frame 2 · Closer lookThe enclosure is screwed straight into the cedar through the flanged mounting tabs: two screws, no bracket, no drilling into the house wall. The thin cable to the right is the 5 VDC feed from the controller.Frame 3 · The Node itselfInside the clear lid you can see the ESP32 module and its antenna leads. The two stub antennas on the left handle 900 MHz (water-meter receive) and the 433 MHz mesh respectively. The white label on the lid identifies the unit as HOA property with a "questions? text" number, helpful when a curious neighbor spots it.
3 · The enclosure
Nothing custom: an off-the-shelf clear-lidded ABS project box. Flanged mounting tabs make it screw-mountable straight to any flat surface; the clear lid means the antenna pattern isn't blocked by metal and you can see the status LEDs without opening it up.
Outline · ABS project enclosureInternal cavity is 115 × 90 × 55 mm (4.53 × 3.54 × 2.17 in). Flanged base brings overall length to 153 mm (6.02 in). Plenty of room for an ESP32 dev board, an SX1262 module, two SMA antenna pigtails, and a screw-terminal expander shield with headroom left for cable strain relief.
What about the rest?
The radio and software side of this Node (protocol decoding, dashboard, emails) is covered on the Node page. If the Node is one of many feeding a central database, the upstream side is the Gateway. For an example of what an installed Node mails out every morning, see the Email sample.
