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Is there an easy way (VI, etc.) to figure zero offset values for grounded channels? The AI Config.VI gives me errors when channels go the least bit out of range and it is almost impossible to add an offset value in MAX that results in a "perfect" zero (I get values that are approx. 0.00004 or less and both + and -; values also vary randomly).
If you need to measure the "zero offset" values, the only way to accurately accomplish this is to tie the (+) and (-) inputs together for each channel and measure the result. I have duplicate SCXI terminal blocks for all of the channels I need to measure offsets and I install this "shorting" block at the beginning of each calibration period. I store these results and subtract them during post-run processing. The raw data is always acquired and stored. I remove the zero offsets ONLY during data processing in order to have "traceable" data acquisition.
P.S. If you are measuring ONLY 40 micro-volts of offset, then I congratulate you. Your data system is very clean. As a point-of-reference, the 6052E series (16-bit) boards have a "best" data resolution of 15.3 micro-vol ts ( 2*0.5 / 2^16 ) for the input range of (+/-) 0.5V. I really doubt that you will be able to achieve better results than you currently measure. It is physically impossible to ever achieve a "perfect" zero value.
