Like this:
http://www.ebay.com/itm/Electric-Solenoi...
or:
http://uk.rs-online.com/web/p/process-va...
The device existed in garden supply store called automatic watering system. You could buy the electric shut off valve alone. It runs on 24V or 12V DC.
Yes, it exists, and to answer your question it is called an electric solenoid valve.
http://www.ebay.in/itm/PAIR-ELECTRIC-AIR...
I have some plastic tubing connected too a liquid dispenser and I want something that i attach to the tubing and if a current goes through it, it closes the tubing to allow liquid through and if no current then it opens. Is there something like this and if so whats it called?
