Hi I am working with a combustion chamber and using a DAQ system (with NI SCB-68 hardware) to read the pressure within the cylinder (as analog voltage). I am trying to output a delayed, 1-millisecond, pulse at 5 volts once the pressure within the cylinder has risen above 5 bar (which corresponds to an analog voltage of 0.25 V). I also want to record 30 ms of samples before the trigger and 220 ms of samples after the trigger. The following image visually shows what I'm talking about.
I have created a LabVIEW VI (which is attached) but I keep running into 2 problems:
- When I run it with Finite Samples after a period of time I get Error-200281which I don't entirely understand.
- Using the "Elapsed Time" Express VI to keep time for the pulse I cannot get a resolution of 1 millisecond, so the pulse is not generated when I set the window between 0.003 and 0.004 seconds for the pulse to be high (i.e. the resolution of "Elapsed Time" seems to be too coarse).
I am a beginner at LabVIEW so sorry if my questions are trivial or if my VI makes no sense but I have been stuck on this for more than a week. Any help would be greatly appreciated!
Thank you,
Morgen