SPAN ADJUSTMENT IN ELECTRONIC WEIGHING APPARATUS

摘要

There is provided a system for adjusting the span of an electronic scale having a double-integrating A/D converter for converting a weight signal into a digital signal. The double-integrating A/D converter has a software-implemented timer for controlling a primary integrating time. The operation time of the software-implemented timer is adjusted linearly or in steps so that a digital value at the time a weight is placed on the scalepan of the scale will correspond to the weight. The adjustment of the operation time of the software-implemented timer is utilized to adjust the differences between gravitational accelerations corresponding to different weights in geographical areas on the earth.