Problem with SCXI system

[SnowBoy111]

I am using SCXI-1121 and SCXI-1163 modules with SCXI-1000DC chassis. I have developed my application in Labview 7. I input an analog signal and upon meeting a certain condition activate channel zero of relay module.I measured the time between meeting certain condition and activation of relay with another precise system. I repeated this process several times. My problem is that the time between meeting certain condition and activation of relay varies from seven to nineteen milli second. Why am I not getting the same time after each repetition? Please advise.

[seymour]

From what I understand, if you write a While Loop in Labview with a very small wait time between loops, the timing will be slightly off between the consecutive loops. Reason being that the timing in Windows is highly sensitive to other processes that are currently running, which could affect the timing of the labview process.

I may be totally off base here, but that is what I have picked up here and there.

Good Luck.

Steve

[Ben]

The correct answer is INDETERMINISM!

As I stated in this answer;

http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=506500000008000000DFC50000&UCATEGORY_0=_203_&UCATEGORY_S=0

Ben