Relative Time out of DAQmx Read Analog Waveform 1Chan N Samp

[DanNatCorning]

I've written an application to display a furnace temp at whatever measurement interval the operator chooses.  The problem is that I cannot seem to get the Waveform chart to display relative time (t0=0:00:00).  Using the DAQmx Read Alanlog Waveform, the default x axis is absolute time.  When I try to change teh x axis to relative time, all of the times are preceded with a large number 906475, followed by the correct minutes and seconds.   I'm a ssuming that, fo rwhatever reason, LabVIEW is spitting out the number of hours since January 1, 1904 ((365days*103 years*24 hours)+(24*(31+28+31+30+29)) + 15 hrs today = 905,847, leaving ~ 26 days unaccounted for (leap years?).  ANYWAY, I cannot seem to get the large number at the front, which I assume represents hours, to go away, so that I can show relative time WRT to t0=0:00:00.  Any suggestions?

[DanNatCorning]

Forgot to post existing code

[Luke_G]

Hi Dan,
The only way that I know of to remove the "large number in front" is to use the "Get Waveform Components" function to retrieve the t0 value. You will need to subtract the starting time from the t0 value, and reassemble the waveform. I couldn't get your VI to run.  It seemed to be missing subVIs.  I built a small example to illustrate this concept as shown in the image below.

1. Get Date/Time in Seconds
2. Get Waveform Components
3. Subtract start time from t0
4. Convert to Time Stamp
5. Build Waveform

Message Edited by Luke G on 05-30-2007 04:41 PM