Control sprinkler with relay shield

I try to make sprinkler (24V AC) control using the Relay Shield board. Anyone has info where I can find the schematic in pdf format ?

For best, if any of u had done this before ?


Hey @Dilbert,

It’s not too difficult. This is from

Basically the wiring is this:

MINUS (-) of AC source to MINUS (-) of Sprinkler

PLUS (+) of AC source goes to COM of Relay

PLUS (+) of Sprinkler goes to NO of Relay

Actually AC has no PLUS or Minus but there’s always a marking for easy reference :smile:

I used to have a bookmark to an Arduino sprinkler system that ran entirely from batteries with its own 24VAC pulses. I currently have a battery-powered Orbit Yard Watering Kit that works really well, and you can pick up extra valves without having to buy another kit. I’ve been wanting to get rid of the brains behind it and replace it with something a little more programmable (by me). It’d be nice to have it water in the mornings (and maybe early afternoons) but only when the soil needs it (using a soil moisture sensor on another remote board). With multiple sensors, you can make it capable of only delivering the right amount of water needed to each zone.

In fact, if anyone knows of a (relatively) simple way to get a Core to stand alone running off 110VAC and switching 24VAC to trigger the valves, I would be all over this project. I just added several new beds to my garden this year, so being able to independently monitor and water them would be amazing. I’m not beneath running physical wires alongside the hoses for remote moisture sensors, either! I don’t know that using 8 Cores in 8 beds is really all that cost-effective!

I found the link I was looking for!

Minty Water Valve Controller


My idea was to replace my existing sprinkler system controller which is indoor. So, the core+relay board is perfect for me as it has 4 zones to control. Last week, finally put my act together to implement the FW in core and SW in PC. Now I can control through the Tinker (making use of existing interface) and HTML (still a draft) in PC.

You should check out the “Looking for some help to control spark via web” where I put some code for controlling four channels of pump on a schedule with start and duration–it would give you a big head start in the right direction for your sprinkler HTML!

I own a small commercial organic farm in California and would like to create my own Ethernet based irrigation control system. The current options that are available for sale are quite expensive and dated in technology. I have knowledge on the irrigation side but I’m a beginner on the spark side. Would anyone be interested in working on the project with me?

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I guess we are always here to help!

Plan your project, list your problem and help needed for our idea and open a new thread when you are ready. :wink: