I have taken on what I thought would be a simple project. I now know I need some guidance. Any suggestions on how to set up this logic would be appreciated. I'm doing this for a non-profit youth organization, so they don't have a bunch of money to buy a new Logo!. I'm using one I already have, 6ED1 052-1MD00-0BA5, which is old, but it works and won't cost them anything.

I have a drink dispenser that pumps the drink into a cup while a momentary button is pressed. The user holds the button down until the cup is full and releases the button. Due to the pump spinning down, the flow of liquid doesn't stop immediately and users routinely overfill their cups. The next time, the user likely underfills their cup, trying to prevent the overfill from the last time. 

I would like to use a Logo! to do this. There are two cup sizes, small and large. I want the user to be able to press and release the button once for a small cup and twice for a large cup and have the Logo! control the timing of the pump. If the user performs a third press and release, the whole system stops. 

Just in case a different cup is used, I would also like to give the user the ability to manually control the pump with a press and hold of the button, just like it does now.

My approach has been to establish two different phases of operation; Timed Control and Momentary Control.

The pump is turned on with any rising edge. Logic determines when to turn it off.

On the rising edge, start a 0.2 second timer. If that timer times out, then the system is in Momentary Control. If the button is released before the timer times out then the system is in Timed Control.

In Momentary Control mode, keep the pump on until the button is released. 

In Timed Control mode use a counter to count the number of releases (falling edge).

On the first falling edge start a 6 second timer. When it times out turn off the pump.

On the second falling edge either ADD 5 more seconds to the timer or set another 5 second timer that starts when the first one times out. If there is a third falling edge stop the pump.

Thoughts on how to do this?

My mistake. That's the number on the side next to the barcode so I thought that was the model number.

Model number is 6ED1 052-1MD00-0BA5

Hello DMirabella,

Yes, something like that is possible with the Logo 5.

A program often says more than a thousand words.So here's an example in the appendix:

B014 = filling time for small cup

B015 = Filling time for large cup

B001 = Changeover time to manual filling

B009 = Blocking time so that the operator can select the large cup without the time for the small cup starting.

Of course you have to adapt the times to the system and your wishes.

Greetings Ella_68

(translated with Google)

Thank you Ella_68, I think I understand your theory of using stops or interrupts. 

I do not have LOGO! Soft installed and the only copy I have at home would be 15 years old. Not sure I could get it to install on Win10 after all this time. Would you be able to post a screen shot of the FBD that you attached earlier? I'm not able to open your LSC file.

Hello DMirabella,

Your old LOGO!Soft should run on its own. At least you can upgrade it to the current version for free. You can find the link here in the forum.

I have attached the program as a PDF.

Greetings Ella_68

(translated with Google)

I found my installation disks for SoftComfort. It's version 6.1 from 2008. To my amazement, it installed on my Win10 machine and is working fine. I was able to open your LSC file and load it onto my Logo! with the USB cable. 

Excellent job on this logic! I hope to someday be able to write logic like this, but it will take me years of practice.

Thanks, again!!!