unfortunately i don't have much concept for the calculations. It's a small project, and i just looked into google and tried understanding the concept. i'm not there yet in my uni courses, if you could point me in the right direction i would appreciate it
the solenoid pulls 1.1amp from exactly 12V
the 4n25 has a max collector current of of 50mA
So i't can't be used directly with the valve.
the tip120 has a max collector current of 5A, and a gain of 1000.
sorry but i dont understand how to calculate the base current.
And i found that pic online, i used it just as reference to know if something like this would work