What is the accuracy of a scaling value in the Tag Configuration Editor?

[stephen s]

I am configuring tags using LabVIEW 7 PDS Datalogging and Supervisory Control Module. In the Tag Configuration Monitor > Tag Configuration > Scaling window, I can set values for the Raw Scale and Engineering Scale. However, when I input a value such as 32767 into the Full Scale box, the value is quickly changed to read 3,28E+4.

what is this actual value that is being used?? Is it the same number as I have entered, or has it been rounded to 32800?

[Khalid]

Hi,

Are you running a non-English operating system? (Because I see a comma in your "3,28E+4".) I tested this here on English WinXP and the changed engineering value I get is 3.2767E+4 (and it works just fine).

A quick way to check if proper scaling is being performed is to create a Tag for the samplenum item from the DataSocket server. Have its raw scale to go from 0-100 and Engineering scale to go from 0-32767. NOTE: make sure you check the Allow multiple writes option for the samplenum item in the DataSocket Server Manager beforehand. Then write to the DataSocket item via a DataSocket connection (not HMI Wizard) and read the value of the Tag using HMI Wizard. A write of 100 will tell you what it is getting scaled to.

H
ope this helps,

Khalid

[Khalid]

Just checked with a French LabVIEW on a French locale machine (to get the commas for decimal points).

The scaling works fine .. it's just the display that gets shortened .. I guess because of the number of significant digits for the control being used. Anyways, rest assured that all works fine 🙂

Regards,

Khalid

[S S]

"Thank you for clearing that up so quickly.

For the record, it is English LabVIEW 7 PDS running on a Deutsch locale machine (Win2K)."