What is a Weston standard cell?

Drawing from Edward Weston's US Patent 494827 depicting the standard cell. Standard cell, extracted from case. Made in USSR The Weston cell or Weston standard cell is a wet-chemical cell that produces a highly stable voltage suitable as a laboratory standard for calibration of voltmeters.

What is a Weston voltmeter?

Made in USSR The Weston cell or Weston standard cell is a wet-chemical cell that produces a highly stable voltage suitable as a laboratory standard for calibration of voltmeters. Invented by Edward Weston in 1893, it was adopted as the International Standard for EMF from 1911 until superseded by the Josephson voltage standard in 1990.

How many volts is a Weston cell?

The correct e.m.f. is 1.4328 international volts, according to Laws Electrical Measurements (1917). Edward Weston (1850-1936) described the Weston Cell in a patent application in 1891. By substituting cadmium for zinc, and cadmium sulfate for the zinc sulfate electrolyte, he created a cell that largely overcame the deficiencies of the Clark Cell.

Who invented the Weston cell?

Edward Weston (1850-1936) described the Weston Cell in a patent application in 1891. By substituting cadmium for zinc, and cadmium sulfate for the zinc sulfate electrolyte, he created a cell that largely overcame the deficiencies of the Clark Cell. It was highly reproducible, had a lower temperature coefficient, and didn't crack unless dropped!

What are the advantages of a Weston normal cell?

The original design was a saturated cadmium cell producing a 1.018 638 V reference and had the advantage of having a lower temperature coefficient than the previously used Clark cell. One of the great advantages of the Weston normal cell is its small change of electromotive force with change of temperature.

How did Edward Weston make a glass cell?

Edward Weston invented the cell in 1893. As shown in Fig. 2, the negative electrode is a 12.5 percent amalgam of cadmium with mercury and the positive electrode is pure liquid mercury. These are placed into the arms of the H-shaped glass cell to make contact with platinum contact wires that are sealed in the glass at the bottom of each leg.