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Float16 tags on PSM tool randomly change their values

Question asked by Noga on Sep 5, 2018
Latest reply on Sep 6, 2018 by Dan Fishman

I am connected to a PI Data Archive server 2016,

and I am encountering a problematic situation after updating float16 tags on the Archive-Editor of the PI-System-Management tool:

After updating values for a float16 tag, I see the updated value appear on the Archive-Editor with the correct value and timestamp (Sometimes I update manually by choosing "Edit value" option on the PSM, or using the simulator.)

The problem appear after about a minute - when I refresh the Archive-Editor page, I see that the values change randomly:

the last 3 digits after the decimal-point change.

 

so for example, I updated the following values on the Archive-Editor for float16 tag:

44.44444

55.55555

66.66666

 

and after refreshing the Archive Editor, the values changed to:

44.44411

55.55589

66.66869

 

Moreover, for some reason the last value appearing in the Archive-Editor is not changed and the value stays correct.

 

What is the reason for that Archive behavior? Is there a way to avoid having the values changed?

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