Batch Simulator with Alternating motors

I was just taking the PLC course as a in major elective to satisfy graduation requirements. Had no idea that I would end up in a job working on PLC's and Robotics, if I knew that now I would have finished the second PLC course (it was 8am my final semester...) covered HMI, OPC's and I didn't see anything past that. Oddly enough my senior project was a PLC/motion control project.

If anyone has some information please let me know, thanks!

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Here is a way to alternate the 2 pumps using only the given addresses in your list, including the 2 counters C5:1 and C5:2. Counter bit C5:1.ACC/0 is used as the alternator bit, meaning that C5:1 must count both pump runs. So the ending Pump 1 Count = C5:1.ACC - C5:2.ACC.

To meet the 5-seconds per pump requirement, set your LogixPro Scans rate to approximatelyl 40%. I condensed the program to 2 rungs to fit it to the allowed site picture size, but you can easily expand it to 5 rungs (System Run Relay, Pump 1 Output, Pump 2 Output, Pump 3 Output, and a Reset Counters rung).

This is what I have so far. As for the 5 seconds, we consider the Accum on the timers reaching 50 as 5 seconds. Once i added the discharge pump the timers will not stop anymore, so I have hit a wall

The picture I posted at the start of this post is not a list that we have to use. We were informed today that those were only an example, he wants our own variation to: Fill the tank using 2 alternating motors so they work the same amount. Then use a discharge pump to drain the tank

We were informed today that those were only an example, he wants our own variation...

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That is great. My earlier alternator version using the counters will work just fine for that scenario.

I notice that in your version, Rung 0 is trying to only control Pump 1. Think about that for a minute. Your "system" must control 3 pumps (Pump 1, Pump 2, and Pump 3), not just Pump 1. So you need a "System RUN" relay that is ON until Stop is pressed, or some other stop condition occurs. I chose internal bit B3:0/0 as my SYSTEM RUN bit. You can pick whatever bit you want to use for this.

You can set the counters to make the system run however many cycles you want (up to 32767). You could also modify it to run forever (until stop pressed) by removing the NEQ and XIC I:1/3 from Rung 000.

Fill the tank using 2 alternating motors so they work the same amount. Then use a discharge pump to drain the tank .

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It is too bad that your instructor is deleting the mixer, heater, and other parts of the LogixPro Batch Mix exercises. Those are also interesting parts to learn, but apparently he likes to simplify the problem for some reason - easier to grade maybe.

If you insist on using timers (really not a good method to alternate these pumps), then this version will do it - if you set the "Scans" speed between 70 to 80 % to even out the timer ACC values for each pump.

But the R2 version included in the attached ZIP file is a much better way using a Counter ACC bit 0 as the alternator bit to choose between Pump 1 and Pump 2 - no timers needed!

If you want to consider other methods, search this site for "alternator methods".