Creating a timer for irrigation.

I'm looking for a way to control my irrigation misting system so that it will emit water for 10 seconds every 10 minutes during daylight hours. The control valve requires 24 volts, which I can supply. Can Arduino do the trick?

Greg Wyche

Can Arduino do the trick?


Great! I know nothing about it. How would one set up something like that?

Great! I know nothing about it. How would one set up something like that?

You need something to keep time. The Arduino can, albeit, not very accurately, but as long as your 10 minute requirement doesn't require a great deal of accuracy, this should suffice. If for whatever reason, you do need better accuracy, you would need an RTC (WiFi/Ethernet). Depending on where you live, the number of daylight hours may fluctuate greatly during the year. If that's the case, you may want to look at getting a light sensor to determine when it is daylight. To control 24V, you would need to determine what the current (amps) requirements are and drive it with a MOSFET/Optocoupler/Relay.

Completely new to Arduino. Looking for a way to control a switch (electrically, not mechanically) which will allow electricity to pass through, from another source, for 10 seconds every 10 minutes. I don't want to use wifi/ethernet, needs to be hardwired. How would this be done?

So, is a relay considered electrical or mechanical? Because it's some of both, but it's electrical controlled by mechanical which is controlled by electrical.

But it might be what you're looking for. In fact, it's probably what you're looking for.

Or, maybe a triac or a MOSFET or a power transistor. That would depend on what you're switching. It is an appliance or pump or valve or fan that runs off mains power? Or is it something that runs off 12 volts or 5 volts?

If you're looking at mains power, look into a a relay or a triac with opto isolation.

If you're looking at DC battery power, look into a relay or MOSFET or power transistor. Depends on how much current you want to switch.

Is the switch something that already exists, or something you plan to provide as part of your solution?

What voltage and current is being switched?

Yes, I think a RELAY is exactly what’s needed. The relay would need to handle 24 Volts to operate a propagation misting valve. The valve would need to operate for 10 seconds every 10 minutes. A very generic schematic is attached.

I am wondering if anyone has the code for this timer. The time is 10 minutes off and the 6 to 10 seconds on. I have tried to find it for days now and have not been able to. I have tried ot alter someones program with no luck. I can get the timer to work but do not know the corret code to display the the seconds on time to the LCD. I hope that someone could point me in the right direction. What i found was on BBQ,Banjo and blues site as a timer heater controller.

I can get the timer to work but do not know the corret code to display the the seconds on time to the LCD

Now you say you found a solution to the problem, and have added to the specs, you want to display on an LCD ?

Have you been able to get the LCD to work yet, with simple, sample code?

Maybe you need to give us an update, what have you got working, and what do you still need to get working.

Yes i have the timer working to where the time on and off is adjustable with a pot. The problem is I do not understand the code to have the on seconds to display. I have the display to light and to display text but I do not understand the code. It is using the pot on Ao and it sees it as % not as time. I need to change the % to time so I can display it. I hope I have explained the problem well enough. Any help would be appreciated greatly.

The timer works, the display works, but not both together?
Read "how to use the forum" and then send us a copy of your script please.

see the open sprinkler project.
Even if you don't want to buy the hardware or use a network interface,
you can see some working code and hardware to see how to control irrigation h/w.
--- bill