Thomson-Houston current indicator
date: label: date made
content: 1889
name: label: maker
content: Thomson-Houston Electric Company
notes: label: Description (Brief)
content: This ammeter consists of a brass current carrying conductor and indicating mechanism mounted on a wooden base. Case missing. Marked: "Current Indicator #2243 Cap. 500 amperes Pat. Oct. 22, 1889, Mfg. by Thomson-Houston Electric Co., Lynn, Mass. U.S.A." The current to be measured passes through a single turn conductor in which is pivoted eccentrically a soft iron movement controlled by gravity. As a result of the eccentricity the current tends to rotate the iron piece into a position nearer to the conductor, causing a scale deflection as a measure of the current. In all meters of this type it is necessary to bring the entire current to be measured to the switchboard and in to the instrument. This necessity was eliminated by the invention of Dr. Edward Weston of the permanent magnet movable coil type of instrument incorporating a heavy current shunt.
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.313284
label: catalog number
content: 313284
label: accession number
content: 181342
objectType: label: Object Name
content: Ammeter
physicalDescription: label: Measurements
content: overall: 3 in x 17 in x 12 1/4 in; 7.62 cm x 43.18 cm x 31.115 cm