Need Help with M3/Hour Totalizer
Hey everyone,
I need to make a 24 hour totalizer for the total outfall of treated water to the ocean. There is a Flow meter measuring cubes per hour right now and I need to sample it and create a 24 hour totalizer that will start at 12am and run for 24 hours then send a number to the HMI in which I will have the last 7 days displayed. I need the totalizer to reset every 24 hours at 12 am so the operator can log the outfall total cubes every 24 hours at midnight. I looked at threads involving totalizers but just want some clarification on this since I'm using a flow meter measuring cubes per hour and my brain isn't functioning well right now brain storming this. I'm using RSLogix 5000 to program this with Ladder Logic. any help is appreciated. regards, Tex 
Do I just take the address associated with the m3/Hr flowmeter and divide it by 60 for minutes, then divide by 60 again for a cube per second value, then move it into another floating point address and add it into it self every second using a continuous timer set at .1000?

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It's a math problem, right?
Most people would want to tantalize every second, so you need to covert what unit you have to X unit/second then add it to the total. If you get X unit/hour, covert it to X unit/second by multiplying it by 1 hour/3600 seconds. 
If you want to avoid rounding errors as your totalizer reaches a large value, then subtract 1000 from your FP totalizer register and add 1 to an integer register every time the FP accumulator is >= 1000, then use a compute function to add the FP totalizer register back to the (INT register x 1000).

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Is there a more accurate way to get the totalizer value? I trended the m3/Hr for half an hour and it never dropped below 30 m3/Hr. I ran a test to see if my totalizer would be close to the average m3/Hr and it was off by quite a bit. For a 30 minute test the totalizer read 13.1 cubes.
Being that the trended m3/Hr shows it never dropping below 30 m3/Hr and ran an average of 31.3 m3/Hr the number over a 30 minute test should be closer to 15.5 cubes. Right now all I have is a continuous running TON timer preset to .1000. That TON timers's .Dn bit is actuating a ONS that's adding the m3/second to itself and storing it as a totalizer value. Is it the PLC scan time causing this or did I program this wrong? Edit ** the routine I'm using to house this logic is in a 100ms cyclic task, should I be using a 1 second cyclic task for this totalizer? 
There is a totalizer instruction in Function Block that works well

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