I have an old SLC 5/02 and I know no way to totalize within the PLC programming because the analog value that I’m working with is in million gallons per day and I need daily totals in gallons.

Is there a way to totalize in the HMI??

I have an old SLC 5/02 and I know no way to totalize within the PLC programming because the analog value that I’m working with is in million gallons per day and I need daily totals in gallons.

Is there a way to totalize in the HMI??

take x samples a day and add it to a tag for a daily total

So I need to setup a dataset and also need to divide the MGD sum by 1440 to get GPM?

Can you use a transaction group to log the values? One reading every minute (as you said, divided by 1440) logged to the database. You can then use a query to sum the daily, or populate a table or graph, or whatever you need to do with the data.

Depending on how often you log a value:

60 sec: sum of the values

30 sec: sum of values divided by 2

20 sec: sum of values divided by 3

15 sec: sum of values divided by 4

12 sec: sum of values divided by 5

10 sec: sum of values divided by 6

6 sec: sum of values divided by 10

5 sec: sum of values divided by 12

4 sec: sum of values divided by15

3 sec: sum of values divided by 20

2 sec: sum of values divided by 30

1 sec: sum of values divided by 60

The more often you take a reading, the more accurate the total becomes, but there is more data being saved to the database. It’s up to you on where your tradeoff point is.