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ue9 analog inputs hardware troubleshooting

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Posted 23 August 2012 - 09:46 AM

Hi My UE9 analog inputs was out today. it's hardware bug. If i look Temp value of the card i have 567C in place of 25C , and Vs at 6.08157V in place of 5V. If i put 0.277 mV on one analog input (with Uni5V select) , i read 2.13V and if i put 0.4V ,i read 4.51V. Bug_labjack_UE9.jpg And that on all analog inputs. It's like the reference voltage of ADC converter was fautly(always at 0.625V or less). Any suggestions to solve this hardware bug. Regards Eric

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Posted 23 August 2012 - 10:43 AM

It does look something in your analog input system has been damaged. Please contact [email protected], refer to this forum topic #5906, and request an RMA.

Make sure you are doing all testing with all connections removed except for USB (or Ethernet/Power). Then add a single wire from DAC0 to AIN0, and use the test panel to vary DAC0 and see if AIN0 reads the same. Also check DAC0, at the same time, with a DMM to see if it is providing the correct output. Try the same thing with DAC0 to AIN1 to see if an odd channel is any different.

Use a DMM to measure VM+ versus GND, and VM- versus GND. They should be about +5.8V and -5.8V:



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Posted 24 August 2012 - 01:03 AM

I test labjack UE9 without anything connect on it , and powered via USB connection. I have test the DAC0 and DAC1. If i put 1.5V to them on the UE9 test panel, i obtain 0.140mv on the DAC's outputs. And if I connect a wire between DAC0 (or 1) to ADC0 (or 1), i can read 1.1V (Gain /range Uni 5V) on the test panel. I have test Vm- and Vm+ , and the both are OK. I contact support for RMA. Eric

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