Loops and system timestamp not synchronized

Question

Running Labview 8.6.1 on Windows 2000, loops and system timestamp (Windows clock) seem to use different time bases; one second in a loop is not exactly as long as a second in system time. If i run a simple VI as in picture, with a 1-second loop which just prints the system time, the printed timestamp goes faster by about 1ms every 4-5 seconds. The same happens using a Timed loop or a While with a Wait until next ms multiple.
Why is that? Can i set a loop to match the system time?
Attachments:
1sec.png ‏3 KB

Answer 1

johnsold wrote:
In the eastern U. S. interconnected power grid the accumulated time is held to within a small fraction of a second when averaged over days.  Over a year the accumulated error is less than parts in 10^12 or better.  The instantaneous frequency can deviate from the nominal 60 Hz by less than 0.1 Hz.
The system basically uses an integral controller referenced to a NIST atomic clock to force the steady state error to zero.
Lynn 
So is that a very technical way of saying "Ben, you are full of Sh#% !"*
I have not measured the frquency of my AC service in the last three decades or so. I do remember seeing it faster in the summer and slower in the winter. Has it really changed? Silly me thinking that the wide freq input spec I read on wall-warts was there just to handle this variation of freq.
And to think it has gotten smarter "without a brain".
Ben
* I am just trying to catch up what I seem to have missed. The above is all in good humor. No offense intended or taken.
Message Edited by Ben on 08-03-2009 12:56 PM
Ben Rayner
I am currently active on.. MainStream Preppers
Rayner's Ridge is under construction