1
\$\begingroup\$

I have a plant that I want to automatically water. I have a plan to buy a small fountain pump which plugs into a wall. I am also going to build a small soil moisture sensor to see if the soil is dry. I want to find a simple way to let power go through the wall outlet to the pump once the sensor circuit is broken from the soil dryness. I am only 12 years old and I don't have a soldering iron so please help me find a way to make a circuit to water my plant. Thanks!

\$\endgroup\$
  • \$\begingroup\$ Where will the water get pumped from? A large pond or something? \$\endgroup\$ – mkeith Jul 11 '16 at 3:51
  • \$\begingroup\$ no a bucket or something like that \$\endgroup\$ – ElectricNoob Jul 11 '16 at 4:02
  • \$\begingroup\$ Can't you just get/make a drip feeder? Basically a tube full of water with a small hole in the bottom to allows water to drip through into the soil. No mechanical or electronic bits required. \$\endgroup\$ – Tom Carpenter Jul 11 '16 at 4:09
  • 1
    \$\begingroup\$ Do this and be done with it. \$\endgroup\$ – st2000 Jul 11 '16 at 4:42
  • 3
    \$\begingroup\$ I am going to suggest that you use a programmable board, an arduino or something, to control a 24 VAC irrigation valve. The 24 VAC will come from a transformer. No pump. The pump creates a lot of problems (pumps will be damaged if run dry). Just make sure the bucket or something is high enough for water to flow to the plant through a bit of hose by gravity. Use a relay to switch the 24 VAC to the valve. \$\endgroup\$ – mkeith Jul 11 '16 at 6:35
2
\$\begingroup\$

For something that a 12 year old budding engineer can work with, how about using an off-the-shelf wireless remote outlet like this $10 one from Amazon and hack the remote control instead of dealing with the AC power directly.

Try it out on your fountain pump. Then you can see if you can make an electronic circuit (transistors and opamps) or computer circuit (Arduino, Rasperry Pi, etc) to read the moisture sensor and control the remote control.

You can either electrically simulate the button presses or you can use one or two servos to physically press the ON and OFF buttons on the remote.

I hope this points you in a good and useful direction for your design. -Vince

\$\endgroup\$
2
\$\begingroup\$

Check out the Sparkfun soil moisture sensor. They have a tutorial that goes over automatically watering a plant based on the sensor reading. They also sell a water pump that operates on 12v DC.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.