Applies To:
  • CitectSCADA 5.00

Summary:
I was having trouble with fast (millisecond) trend display. I have installed Version 5.00 Service Pack C but I am still getting glitches when entering the page or when changing from history to real time. Can this problem be fixed? 

Solution:
The problem lies in the fact that the Trend Server quantises the data for millisecond trending on second boundaries. So for a 100ms trend when requesting 485 samples (VGA Trend template) it bumps it up to 490. The actual problem is that when the client gets the 490 samples it says it only wanted 485 so only uses the first 485 and ignores the last 5 - and hence the gap - it should be using the last 485 and ignoring the first 5.

CIT has confirmed this to be a problem in Citect for Windows versions 5.00. This problem has been fixed in version 5.00 Service Pack D.

 

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