Humboldt State University ® Department of Chemistry
Weston Electrical Instrument Corp.
The Weston Electrical Instrument Company was founded in 1888 and immediately started selling a moving-coil DC millivoltmeter of Weston's design. Weston meters immediately became the world standard for accuracy, a status they held for much of the 20th century. Weston DC ammeters were available by 1894. Weston's AC meters were perfected and ready for production by 1891. By 1893 Weston had developed and was using the alloy Manganin for the series resistance coils in voltmeters, which has essentially zero temperature coefficient for resistance. This allowed greater precision.