[Kevin Sevcik]

Originally Posted by 1075guy

Not sure why you think that you couldn't run a spring return cylinder on a 5/2 valve.

5/2 single solenoid valves typically used in FRC have 3 ports on the input side (EA, P, and EB), and 2 ports on the output side (A, and B). When the solenoid is not energized, P->A and B->EB. When the solenoid IS energized, P->B and A->EA. If I connect my spring return cylinder's port to B, and plug A (either with a brass plug, or a hose to a T that has a loop of hose between its other two legs), this will work perfectly.

Truly, I have even built a pneumatic system on an FRC bot that could stop in the middle of its travel by using a second valve to control whether or not EA/EB goes to atmosphere.

*clears throat*

Originally Posted by Kevin Sevcik

I've seen 5/2 valves out there in FRC. That's actually the style that Vex sells. A 5/2 valve is always sending pressure to one of the output ports. You'll need to plug one of the outputs in that case, or you'll end up dumping pressure to atmosphere when you're exhausting the cylinder.

But, of course, if you have a 3/2 valve, plumbing is a lot simpler and less prone to leaks.