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Unread 28-02-2008, 01:36
Guarana Guarana is offline
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Re: How do you control the length a piston will extention/retraction?

Quote:
Originally Posted by 1075guy View Post
This is incorrect. The 2nd valve will not switch without pressure in the P hole. I believe the SMC valves require about 20psi to switch. A method that will work, is looping the A and B ports together on the 2nd solenoid, feeding EA, EB, or both from solenoid 1 to the P port (for one direction, the other, or both) on the 2nd solenoid. plugging EA, and leaving EB open to atmosphere. I would recommend using a Single Solenoid for the 2nd one.

Basically the system looks like this:

Pressure in-->|Solenoid 1|-EA------P-|Solenoid 2|--EA--|
...................|________|-EB-/..........|________|--EB------
......................A|....B|.................... A|....B|
................----|cylinder|.....................\___/
with this, the pneumatic will stop when the sol 2 switches to A. when its on B it will move freely. is this correct? trying to figure out programming real quick.