NI-USB 6008 reading in voltage problem

[zepp2]

Hi

I am trying to program a USB-6008 on a mac. When I connect the Analog input to the 5V output I get a reading of 3.67volts, while on an osscilascope I read a voltage of 5volts. Is this to be expected? Do I need load resistors? Also I get the same effect when outputting voltages for the analog output. 

[zepp2]

I have also tried this with 2.5V and get 1.1 volts

[BB. · Accepted solution]

Hi Zepp2,

Thanks for your post. Which pins are you connecting together on your device? Dependant on the type of connection you have the wiring may not be quite right.

I have found a few online documents which hopefully should help you out:

Field Wiring for analog signals

USB-6008/6009 Getting Incorrect Voltage Readings

USB-6008/6009 Analog Input Reads Approximately -1.4V Offset

Please let me know if any of these help you out.

Regards,