Hello,
This question is best asked using an example.
I currently have a tag that has a calculation hardwired into the code.
for 1/1/2000 to 5/5/2013 we calculated the tag (I95-000-FR) to equal A * 36 / 2000
I now want the same tag to equal B * 36 / 1000 * 5 for any dates AFTER 5/5/2013
After the update, I want to be able to run PI in excel for 1/1/2013 to 5/23/2013 and all the data prior to 5/5/2013 to be calulated the OLD way and all data after 5/5/2013 to be calculated the NEW way.
I also want to be able to show what equation was used on any given day/time period.
So, my question:
Is there a way maintain the historic values (any time before 5/5/2013) and keep a record that the equations used at that time?
Does PI have the capability of archiving old equations?
I do not want to have to create a new tag.
As a note. I am not a "PI-guy", so I do not know coding. I just use it every day.
Thank you.