Characteristics
The original design was a saturated cadmium cell producing a convenient 1.018638 Volt reference and had the advantage of having a lower temperature coefficient than the previously used Clark cell.
The temperature coefficient can be reduced by shifting to an unsaturated design, the predominant type today. However, an unsaturated cell's output decreases by some 80 microvolts per year, which is compensated by periodic calibration against a saturated cell.
Dr. Frank Alfred Wolff (1873-1946), NBS Researcher and 1st Chair of the Washington AIEE Section contributed significant research to the studies of the Weston Cell.
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