Problem With PXI-6220 SCXI-1102B

[wenyan]

A system with PXI-6220 and SCXI-1102B(the block is 1308)is built to measure voltage. But DC voltage of 1V is measured as NOT DC, and the highest voltage measured is 1V. What may be the matter?
Thanks!

Message Edited by wenyan on 05-05-2005 09:15 AM

[George M.]

Hi,

How are you measuring this voltage? What voltage source are you using? How is it not DC? Which driver version are you using? Can you measure any other voltages?

Let me know. Thanks!

George

[wenyan]

I use the DAQ version 7.4 and the voltage source is common DC 0-30V. I used the following codes to measure:

DAQmxCreateAIVoltageChan(taskOut, "PXI1SLOT1/ai0", "Voltage0",
DAQmx_Val_Diff, 0, 5, DAQmx_Val_Volts, "");
DAQmxCfgSampClkTiming(taskOut, "",1000, DAQmx_Val_Rising,
DAQmx_Val_ContSamps, 5000));
DAQmxReadAnalogF64 (taskHandle, 1000,10.0,
DAQmx_Val_GroupByChannel,data,
1000,&actualSamplesRead, 0);
PlotY(panel,PANEL_GRAPH,&datasamplesToReadPerChannel*i],
actualSamplesRead,VAL_DOUBLE,VAL_THIN_LINE,
VAL_EMPTY_SQUARE,VAL_SOLID,1,ColorArray[i]);

The wave I measured was not DC,but liked the pulse wave ,the max voltage is 1V, but the min voltage is 0V.

I have not measure other voltage.

Thanks!

[Sean_C.]

Hello,

Have you tried measuring this signal from within Measurement and Automation Explorer (MAX)? If not, do so. Right-click on the SCXI-1102B module and select "Test Panels." If you still read incorrect values, verify that the signal source is outputting the correct values. Try measuring the signal with an oscilloscope or a multimeter.
If you still cannot read a correct signal, try using a different DAQ device for your SCXI communication.

Let me know your results.

Regards,
Sean C.