Hello forum! I'm building a small automatic watering system on my balcony.
It will consist of two 12v water pumps and three valves, controlled by an arduino, a RTC and a WiFi controller. The valves and pumps will be powdered by solar panel and a 12v battery and the controller, WiFi and RTC by a 6v battery (also charged by solar).
There will be three valves attached to a small water tank somewhat above my plants in height. I want to open a valve when it's time to water the corresponding plant box and have the water drop down into the box by gravity.
I've found a solenoid direct valve that will open when given power and close (by spring or magnet or something) when power is turned off.
This could possibly be done with a relay on each valve, each relay connected to the 12v battery and to a separate pin on the arduino board.
Is there some way that one could control the three valves from one pin on the arduino?
Does there exist some kind of relay/transistor that can take let's say three different signals from the controller (for instance low, medium and high), and then relay the full 12v signal to the valve that correspond with that particular input signal?
This will be my first introduction in electronics/arduino project of any kind and that is why I am asking, to lean a bit more. I have spent many days now reading up on the basics of electronics and looking at arduino water systems online but I haven't figured out what device I could use here.
There is no wire diagram yet (haven't gotten to that part yet) but I hope the images of the planned circuit can be of help.
In advance thanks for any answer.