Hi,

I'm trying to help mentor some gcse kids and several are doing electronics,
One wants to make a circuit for his project that automatically waters plants.

Now I know a little bit about electronics, but not loads....I know they can't use pic chips at the school (no facilities) and reckon that it'll be an astable circuit I guess with a 555 timer with a variable resistor and capacitor to 'sort out the timing' but presumably then it should go onto a solonoid/motor to open a valve for the water device.

Anyone got any ideas that could help.

SOrry if I shouldn't post this...as my name suggests I am new to all this.

Cheers

 

If you want to get a bit trickier than just a 555 timer and a solenoid, there are linear flow controllers available too. It's a good chance for your kids to get their feet wet (or at least their plants wet) with op-amps and such.

eric

 

Hello,

Here is a small circuit for a plant watering watcher.
http://www.redcircuits.com/Page18.htm
Parallel to R7 and the led there can be a smal relais to control the pump.

Greetings,
Bertus

 

Here's a start:
http://homeautomation.wikidot.com/plant-watering
Found by Google search: http://www.google.com/search?hl=en&safe=on&q=plant+watering+system+schematic

To automate the detection of soil moisture content, one could use something like this:
http://www.redcircuits.com//Page18.htm
Found here: http://www.discovercircuits.com/S/s-water.htm
Using this search: http://www.google.com/search?hl=en&safe=on&q=plant+moisture+schematic

 

Thanks for your all help guys! much appreciated

 

Thanks for your all help guys! much appreciated

I would also like to thank you for investing your time in getting kids to be enthusiatic about science in general and electronics specifically. Who knows how many of the kids in your group will go on to greater things.

hgmjr