RSLogix 500 Flow Meter Totalizer Signet 2551

[bearsgone]

Hello
I never used STI before and not sure how to configure it correctly. I have logic LAD 3 and PFN having a value of 3 however LAD 3 is still ignored. Not sure what I am doing wrong

 

[MATT116]

I've never setup this up in the function file nor have I ever programed a 1400 but I think your problem is you don't have a value entered in the SPM I think it needs to be 100 100x10mS=1 second. In my sample program go to processor status>STI Tab there you can see where I entered the parameters.

 

[bearsgone]

MATT116

Changed SPM to 100, unfortunately no change

 

[MATT116]

Were still missing some step.
Go to the Allen-Bradley Literature library select search by publication number and enter 1766-RM001B-EN-P.
In this manual it talks about setting up the STI with a ML1400

 

[MATT116]

Try setting the TIE or AS to 1 to enable them. Looks like setting AS to 1 automatically sets TIE.
Goto page 323 of the above mentioned PDF

 

[bearsgone]

Thank you for your help. I had to set:

PFN: 5
UIE: 1
TIE: 1
AS: 1
SPM: 1000

 

[MATT116]

So it is working? as in keeping track of the GPM accurately?

Make sure you have something in your logic that will reset the totalizer be for it faults the PLC

 

[sthays10]

Matt -

Thanks for this help.. Found it through a search and it was exactly what I was looking for. I increased the interval to 250 msec and decreased C5:0 to 12 (that way, it will increment the total every 5 sec instead of every minute).

I am running on an emulator right now, and it doesn't seem to be running at the correct intervals (it only does about 50 seconds for every 60 seconds of real time), but I expect when I get my PLC up here for testing, it will resolve itself.

Thanks again - this program really helped.

 

[MATT116]

So you set the STI interrupt to 250ms?

On another note I've found that doing a FIFO of the total when ever the the totalizer is reset is a good thing that way you/operator can always look at the previous total.
Also depending if the PLC has a memory module and how that is set up you may need to protect the data tables that you are using for your totalizer from the memory module writing them back to 0.

O-yea what PLC processor are you using?

 

[sthays10]

We are going to be using a 5/05. The panel has been built but is waiting on the safety guys to approve it.

How do you set up a FIFO for totalizer resets? How many values do you keep? We are planning on having a non-resettable and a batching totalizer.

 

[MATT116]

What ends your batch? does this also reset the totalizer to 0? Look at what happens on rung 4 of the example program I provided. when the total reaches 10mil it resets the totalizer to 0 using the MOV instruction. So before you reset the totalizer use a MOV instruction to move to total into a new F file this will be you previous total.
As for how many previous totals to keep thats up to you and the customers.
Hope this helps

 

[MATT116]

see attached example