Microcomputer-Based Calibration Systems for Variable Voltage Dividers

Two microcomputer-based systems for the calibration of ac and dc multidecade voltage dividers at NRCC are described. They permit the self-checking of the reference standards, the comparison with the test dividers, and the complete processing of the measurement data to be carried out orderly, accurately, and cost-effectively. The uncertainty in the ac voltage ratio calibration of the reference is less than 5 X 10-8 of input at 400 and 1000 Hz. For dc, the 13-bit reference standard can be automatically calibrated with an uncertainty believed to be less than 1 X 10-7 of input.