# New to pneumatics



## bwswede (Jun 7, 2017)

Great forum you have here! I am hoping to get some help from someone with more experience than me.

I have just set up a system that has two double acting cylinders acting as single acting cylinders with a spring return (exhaust on the cylinder). They are each fed from a separate 5 way 2 position electric solenoid on the same manifold.

Everything seems to be working as planned except that when I release the pressure (momentary switches on each) the cylinder not being pressurized jumps (extends very briefly) when the other cylinder's pressure is released. 

It is as if when power is removed from solenoid "a" and its spring returns it to the at rest position there is leakage in the process that sends pressurized air to solenoid "b" which in turn makes its cylinder jump. What I don't understand is how this is happening because the port that sends air to the cylinder is closed.

Any ideas?


TIA,
BWSwede


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## wickedbeernut (Dec 14, 2016)

Hi BWSwede,

Can you sketch the set-up on a napkin and post a pic?

wbn


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## 69-cat (Jan 18, 2014)

If you are using DC solenoids, it could be the spike that is created when you power down a DC coil. If this is the case, it could be fixed by installing a diode across the leads that feed each coil. This will bleed off any spike that is generated during the power off cycle. But reading the question again, a picture would be the best way to help you.
Dave


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## bwswede (Jun 7, 2017)

Testing...


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## bwswede (Jun 7, 2017)

Finally I am able to reply. I typed two long replies but neither were accepted because of some kind of token.

Thanks for the replies. I appreciate your willingness to help. I have it figured out now.

BWSwede


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## David_AVD (Nov 9, 2012)

What was the answer? It will likely help someone else.


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## bwswede (Jun 7, 2017)

One of the cylinders is 3" x 10" and when it discharged 125 psi air into the exhaust manifold it overwhelmed the muffler I had installed. The air, like everything else in life, looked for the easiest route so it back fed into the other cylinder through the manifold exhaust chamber and caused it to jump. The jump was quick and only lasted as long as it took for the air to exhaust through the muffler on the manifold.


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## David_AVD (Nov 9, 2012)

Good to know. Thanks for that.


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