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Garden Watering System – Part 4 – Software

In previous posts I wrote about the hardware and electronics I used to build...

Garden Watering System – Part 3 – Electronics

Electrically, the solenoid valves used in the watering system are fairly simple: The valve is normally closed, and no water flows. When power is applied to the solenoid, it opens the valve. The valve stays open as long as the solenoid is held on by the electrical current, and is then closed by the water pressure when the electrical current stops. The solenoids typically run at 24 volts AC, or 12 volts DC. Each solenoid draws about 500mA current at 12VDC when switched on. This means that to turn the water on and off electronically, you need a way to switch 24VAC/12VDC at up to 500mA.

Garden Watering System – Part 2 – Pipes

In Part 1 I introduced my new garden watering system and the components used to switch water on and off. In this post is more detail on connecting the pipes and other hardware parts needed.

Garden Watering System – Part 1 – Introduction

I like gardening.Something I have always wanted to do is automatic watering of the garden.

This year I have put a lot of work into upgrading my garden watering system – from software to the controller, valves, pipes, and sprayers. It’s nice to know plants won’t die over the summer even if I forget or am too busy to hand-water them, and to know that seeds won’t dry out and fail to germinate because of a single missed watering.

As well as running pipes and wires, I wanted to build my own controller – a device that automatically switches the water on and off. A typical controller allows you to set watering times for each day of the week. I wanted to go further and have an internet-connect controller that I could log into and change the settings remotely.

This post is mainly about the initial steps for the new system, and the old system it replaces. Part 2 will be about running the pipes, part 3 the controller hardware details, and part 4 will be the software details.

I hope these posts will help you set up or improve your watering system so that you can enjoy great results too.

3.3V Power Supplies

In this post I look at linear and switched regulators for 3.3V power supplies, build up some experimental circuits, and examine the performance and failure modes of different types of regulator circuits.