The 2553A Precision DC Calibrator, Pursuing High Accuracy and Stability with Inherited Usability

摘要

Yokogawa Meters & Instruments Corporation has recently developed the 2553A precision DC calibrator. Functionally, the 2553A uses the same dial operation and seven-segment LED as those of the previous 2553 model, inheriting its excellent usability and visibility. Meanwhile, the 2553A has doubled the number of types of thermocouples that can be calibrated, from five to ten, in order to deal with a greater variety of thermometers and temperature controllers; and it has newly implemented a resistance output function for devices that use resistance temperature detectors. In terms of performance, the 2553A has achieved high-speed zero/full scale calibration and output correction of its digital to analog converter (DAC) by introducing a digitally assisted analog technology that uses a field-programmable gate array (FPGA). As a result, the 2553A offers a high accuracy of ±75 ppm/year for DC voltage, ±120 ppm/year for DC current and high stability of ±15 ppm/hour for DC voltage. This paper introduces the major features and key technologies of the 2553A.