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On-board autocalibration of analog I/O circuits ensures the highest accuracy of your analog measurements over both time and temperature. Improved accuracy of measurement translates into improved performance of your own system and improved customer satisfaction.
Autocalibration also eliminates downtime for maintenance and the possibility of human error during the calibration process, reducing the total cost of ownership for your final product.
Diamond Systems’ unique multi-range autocalibration system provides the highest accuracy of any commercial autocalibrated A/D board by providing a unique set of autocalibration adjustments for each input range. This eliminates the inherent gain and offset errors that exist in any programmable gain circuit. Competitive A/D boards ignore these errors and provide a single calibration adjustment for all ranges, meaning that you only achieve rated accuracy for a single input range.
The graph above shows the difference in errors between our Diamond-MM-32-AT autocalibrated A/D board and a competitor's manually calibrated A/D board over a temperature range from -40oC to +85oC. Hercules III uses an autocalibration circuit almost identical to the DMM-32. Maximum error on the non-autocalibrated board is 0.3 percent, reducing the effective A/D resolution to about 8 bits! Maximum error on the autocalibrated DMM-32 is only 0.03 percent, a 10-fold improvement in accuracy.
(Error on autocalibrated board is due to temperature drift of on-board voltage reference chip.)