CTU Count Up tenths and hundreds separately Logix500

Hello, I have a flowmeter, it pulses once per gallon.

I have my discrete input pulsing away along with the flowmeter.

I can count the tenths portion fine, but I wanted to extend my counter 'resolution' by separating pulses 0-99 by a separate counter for hundreds, thereby giving me 32767 gallons until overflow occurs.

I have two lines of code, one, a CTU counter counting up. I want to reset the counter after 100 pulses and increment my second CTU by one. I used the preset field, but this does not help. It seems simple, anyone out there have a similar way to do this that works?

Also, should I be using retentitive counters? Thanks!

Tim

Greetings Tim ...

if I understand your question, you might skip the counters and use something like this instead ...

and all Allen-Bradley counters are already "retentive" ... specifically, they don't lose their "counts" when the power is cycled ... is that what you meant? ...

Hi Ron,

Thanks for the tip! I am going to try this right now, seems like a smarter way to write a pulse counter.

Thanks.

Tim

Ron, Brilliant! Thanks very much.

I have two lines of code, one, a CTU counter counting up. I want to reset the counter after 100 pulses and increment my second CTU by one.

Click to expand...

Ron's method is elegant and keeps the rungs to a minimum for even large numbers. But if you are curious how to get your original idea to work (how to cascade two or more counters), here it is. The One Shot Rising is needed in case the Input is still on after C5:0 is reset by Rung 001.