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cezarica    505

Hi.

I got an in-line package stacker and want add a second gas pipe element sensor in the empty pipe space to eliminate any gases that I don't want in there. In order to achieve this i was thinking I need to cover 2 scenarios in order for the gas shutoff to open:

- if S1 sends green and S2 sends green then the gas shutoff should open and let the gas package at S2 exit since it's the gas I want and it was stacked
- if S1 sends a green and S2 sends a red then the gas shutoff should open and let the package at S2 out since between them there's another gas package that I don't want (same for S1 sending red and S2 sending green).

So with these rules in mind I was thinking that a AND gate would solve the first scenario, meaning S1 and S2 sending green, and if I add a NOT gate on the AND gate's output I should basically cover the second scenario, where either S1 is sending a green and S2 is sending a red, the other way around or both sending a red (basically covering the AND gate results).

So, I decided to test with some switches and a AND + NOT gate and see what happens.


flop-min.png.d1697156d34708396fe3fdd5323e6345.png

I was expecting the power shutoff to switch to on when the two signal switches send a green signal and turn off in other case, but to my surprise the NOT gate change the AND gate output and that made the NOT change it's state that in turn changed the AND gate's state and from this point onward stuff repeats, basically resulting in the power shutoff switching on and off very fast.

Isn't this NOT gate output changing the state of the AND gate output? Shouldn't the outputs be changed only by the inputs of said gate element? Is there another way to make the in-line gas stacker work only with a single gas and kick out everything else? :)

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mathmanican    2425

You have connected the head and tail of a not gate. This is what causes the problem.  The output of the AND gate is still red (false), but green overrides any red signal, so the green from the front of the and gate comes back. This all happens very fast.  

You can achieve the same thin by connecting the input and output of a NOT gate anywhere. As long as no GREEN signal shows up in the line, you will get lots of flicker.  It's been like this since the gates were introduced. 

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cezarica    505

Yes, I need to negate the AND's gate output and at the same time need the AND's gate normal (not negated by the NOT gate) output connected to the same element I want to control, so inevitably the both ends of the NOT gate connect.

Guess will have to take a different approach on this.

Edited by cezarica

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mathmanican    2425
8 hours ago, cezarica said:

Yes, I need to negate the AND's gate output and at the same time need the AND's gate normal (not negated by the NOT gate) output connected to the same element I want to control, so inevitably the both ends of the NOT gate connect.

Run the output of the AND gate into the input of an OR gate and the NOT gate you chose.  Then connect these together. Sounds like you're making an edge detector.  Search the forums for lots of posts on this. Use google's site: option for getting better search results. You'll find quite a few. 

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Sigma Cypher    72

Uh ... are you sure Saturnus's packet stacker works with mixed gasses? Unless I am mistaken (again) we would need an "any gas" category in the gas pipe element sensor for this to work.

My guess is you will have to filter for your desired gas first, and then stack the packets, like this:

image.thumb.png.1b350442fa5294d8dcb2ba7ead084100.png

image.png.4ffb045c5f8012ff2cd35dda0fddc95a.png

image.thumb.png.6d038789468d68aabb0b7381f9948e83.png

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cezarica    505

Will try what you said @mathmanican, for the sake of science obviously. Didn't knew what to look for so opened a topic. Thanks for the tip.

@Sigma Cypher I know that the in-line stacker works with just one type of gas, hence why i was looking for a way to remove anything in between, but didn't want to add another gas shutoff. I've done a gas pipe element sensor connected to a NOT gate that has it's output connected to a gas shutoff to filter out anything that's not the desired gas and let anything else continue down the pipe. Now the stacker receives only what it should and works as intended. :)

Edited by cezarica

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Sigma Cypher    72
4 hours ago, cezarica said:

but didn't want to add another gas shutoff.

Got it.  So how did you pull this off?

4 hours ago, cezarica said:

I've done a gas pipe element sensor connected to a NOT gate that has it's output connected to a gas shutoff to filter out anything that's not the desired gas and let anything else continue down the pipe.

Sounds like the set-up I showed you except you have the white side going to the desired output instead of green.  You're welcome :-)

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