the datasheet of the valve is here: http://www.clippard.com/downloads/PDF_Documents/Clippard%20Full%20Line%20Catalog/Clippard%20Catalog%20by%20Page%20Number/167-225%20Electronic%20Valves/Page%20190.pdf
it is a solenoid valve, look at this table:
|Nominal Voltage Range @ 73°F (VDC)||Input Current Range (amps)||Coil Resistance @ 73°F (ohms)||Max. Voltage Required (VDC)|
|0 to 5||0 to 0.370||13.5||6.2|
|0 to 10||0 to 0.185||54||12.4|
If I want to use the 5V model it will need 0.370 A as maximum current, but Arduino can only output 40mA.
Maybe something like this guy does could work?http://bildr.org/2011/03/high-power-control-with-arduino-and-tip120/
are you suggesting me something like this: http://www.learningaboutelectronics.com/Articles/Unity-gain-buffer
The idea is to power the circuit with a battery (6V or 9V), which can be used also for powering the valve of course.
guys, thanks very much for your suggestions, if you have any further comment, examples or schematics, I would be very grateful !