Vacuum cutoff solenoid
 

I haven't been able to figure out the answer to this one. On the side of the body of the SMC double solenoid valves are two small ports labled PE and PX (I think). Does anyone know what these are for? The reason I am asking is that we are considering mounting this solenoid in the vacuum line to "lock in" vacuum. The problem is that the solenoid valves are pilot actuated, requiring a minimum of around 20 psi to actuate. So in order to actuate the valve we need to apply a pilot pressure. So are the PE or PX ports for an external pilot pressure? The people want to know!

Re: Vacuum cutoff solenoid
 

Try this post or search under vacuum solenoid.

Good luck!
Don

Re: Vacuum cutoff solenoid
 

Thanks for the "search before you post" response. However, your suggestion (and others generated from search) no not answer MY question. Which is essentially, what do the small PE and X ports do? As in is the kit double solenoid able to actuate in a vacuum environment if provided pilot pressure via one of these ports?

Re: Vacuum cutoff solenoid
 

I was wondering the same thing, looking at the valves the other day. I would assume so, looking at the extremely small size of the input. I do not however understand why there would be two ports, and not just a single "pilot" line.

Re: Vacuum cutoff solenoid
 

After staring at the drawing of the internal paths, I am guessing that the PE and X ports are for venting pilots' pistons and therefore would not work for providing external pilot pressure. SMC has other valve models that are designed for this. The internal pilot pressure path branches off of the P port at the top of the valve body. The PE and PX ports vent off the backside of the actuating pistons allowing them slide back and forth.