Westinghouse style 35248 precision voltmeter
date: label: date made
content: 1908
name: label: maker
content: Westinghouse Electric and Manufacturing Company
notes: label: Description (Brief)
content: This instrument consists of a precision voltmeter of 150 volts with 1,000 ohms enclosed in a polished mahogany container in a leather case; marked “Westinghouse Elec. & Mfg. Co. / Serial #45562”. This is a torsion head spring controlled voltmeter consisting essentially of a Kelvin balance type of system with two moving coils each acting between a pair of fixed coils. The electrodynamic force between two sets of coils carrying the current, one fixed end the other movable, is balanced by winding a spring by means of a torsion head carrying a graduated dial. It is difficult, with this type of instrument. to balance and therefore to measure current or voltage unless it remains very constant.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Weston Electrical Instrument Corp., thru John H. Miller
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.313275
label: catalog number
content: 313275
label: accession number
content: 181342
objectType: label: Object Name
content: Voltmeter
label: Other Terms
content: Voltmeter; Measuring Devices
physicalDescription: label: Physical Description
content: leather (case material)
label: Physical Description
content: wood (case material)
label: Measurements
content: overall: 8 1/2 in x 10 1/4 in x 9 in; 21.59 cm x 26.035 cm x 22.86 cm