Problems of PCI 6036E

[Vencent]

I have some problems with my PCI 6036E. I used it to acquire the signals from transmitters. The voltage signals were isolated before connecting the BNC 2090. I configured the input mode as DIFF MODE according to the manual. The DAQ system worked well. But a few days ago, some problems happened. The voltages acquired were not consistent with the analog signals connected to BNC 2090. For example, when the analog input was +2 V, the acquired voltage was -8 V. And if the analog input was -5 V, the acquired voltage was +5V. Similar results could be obtained if we changed the input analog signal. I had changed the input mode as SE MODE with NRSE, but the similar phenomena occured.  I used the DAQ Diagnostic Utility 1.0 with DAQmx 7.5 to diagnose the DAQ card. The self-calibration, AI test, AO test failed, as you can see in the following. What's problem with my PCI 6036E? DO I need to return it for repair or calibration?

*******************************   Diagnostic result ********************************** 

2009-5-17 22:32:11

Selected Device: Dev1

Device Type: PCI-6036E

Serial Number: ********

Device Support: (PASS)

NI-DAQmx Version: 7.5 (PASS)

Device Reset: (PASS)

The device was last self-calibrated on: 2008-5-20 3:21:08

Running Calibration ...   FAILED for the following reason: 

Error -200545 occurred at DAQmx Self Calibrate.vi

Possible reason(s):

Self-calibration failed.  The self-calibration date has not changed.

Disconnect the device from external signals, as they might introduce noise.  Externally calibrate the device to recalibrate the onboard voltage reference that is used for self-calibration.

-------------------- Testing Counters... --------------------

Testing CTR Buffered Pulse Generation...   (PASS)

Testing CTR Single Pulse Generation...   (PASS)

-------------------- Testing Analog Input... --------------------

Testing AI Ground Reference...   (FAIL)

************ Test FAILED for the following reason ************

Analog Input was not within tolerance for ground reference.  Expected to read: 0.000000  Actually read: 9.899129

*******************************************************

Testing AI Voltage Reference...   (FAIL)

************ Test FAILED for the following reason ************

Analog Input was not within tolerance for reference voltage.    Expected to read: 5.000000  Actually read: -5.000778

*******************************************************

Testing AI Finite Sample Clock...   (PASS)

Testing AI Finite Sample Clock Frequency...   (PASS)

-------------------- Testing Analog Output... --------------------

Testing AO Finite Sample Clock...   (PASS)

Testing AO Finite Sample Clock Frequency...   (PASS)

Testing AO Single Point...   (FAIL)

************ Test FAILED for the following reason ************

This test failed to output 9.000000 Volts on Dev1/ao0.  The actual value written was -1.000228.

*******************************************************

Testing AO Accuracy...   (FAIL)

************ Test FAILED for the following reason ************

This test failed to generate a voltage waveform with an error of less than 0.076208 Volts on Dev1/ao0.  The actual average error was 9.999581 Volts.

*******************************************************

-------------------- Testing Digital IO... --------------------

Testing DIO Lines...   (PASS)

Testing DIO Ports...   (PASS)

 ----- DIAGNOSTIC TEST COMPLETE -----

[Jason_D]

Vencent,

Do you see any correlation between the input value and output?  The 2 you mentioned here seem to be fairly random and this coupled with the prior working of the card suggest that the card is in need of repair. 

I assume we disconnected the device before running this utility?  If so it would appear that we are getting some very strange results. 

[Vencent]

Yes. There exists some correlation between the input value and the output. It follows this equation:    abs(input)+abs(output)=10 V.  That means when the input is positive, the output would be -(10-input value). And if the input is negative, the output would be 10+input value.I got these readings whatever I connected the signals in DIFF MODE or SE MODE (NRSE). That's very strange.

I disconnected all the devices from PCI 6036E, and ran the diagnostic utility. The diagnostic result was post in my last message.

[Jason_D]

Vencent,

Sounds very strange indeed.  This very possibly could need to be repaired. 

What happens if you open up a test panel.  Set the AO to some value and then monitor the ao0_vs_aognd verifying you see roughly the same value that you had output.

Thanks,

Vencent

[Vencent]

I have tested the AO channels. The outputs are ok.

Well, I have sent the card to the local agent for repair. Thanks for your kind replies.