OpenDispenser

this is a simple project to fix a 12v water dispenser

Item list: 1x Arduino Uno; 3x 12v Solvenoid Valve; 3x NPN Transistor (in my experiment i use TIP120); 3x 1N400x Diode (in my experiment i use 1N4001); 6x 1K Ohm Resistance; 1x Membrane button array;