Wallace "Telemachon" direct current generator with laminated armature
date: label: date made
content: 1875
name: label: maker
content: Wallace & Sons
notes: label: Description (Brief)
content: Electric light machine. Nameplate reads: "Manufactured by Wallace & Sons, Ansonia, Conn." This electric light machine was constructed in November 1875, and was called the "Telemachon" by Wallace. It was exhibited at the Philadelphia Centennial Exhibition of 1876. A record in the Wallace & Sons shop stated that this dynamo was driven at a speed of 1000 RPM and supplied 11 arc lamps when driven by a 1.25" belt. One brush is missing from this specimen, and a pulley wheel is partly broken.
label: Description (Brief)
content: The original "Farmer" field contained two six-pole field magnets, each requiring six brushes. Wallace modified the field by connecting three poles together for one polarity, the remaining three for the opposite, thus making a two-pole field requiring only two brushes. This change increased the output of the machine. The armature is a Gramme ring, built up of thin sheets of iron, the plates being separated by paper. It is believed to be one of the first laminated armatures.
label: Description (Brief)
content: At a convention in Providence in 1891, Frank Sprague quoted an experiment at the Wallace Ansonia Plant, during which he observed this machine being run as a motor at two or three thousand RPM, and the rotational motion being stopped by a strong workman throwing his arms around the pulley. Sprague observed that both he and Wallace overlooked the fact that the total work done by the machine was actually equal to the torsional effort multiplied by the speed of the pulley rim. The device was also exhibited at the Franklin Institute Fair of 1884 and the Chicago World's Fair of 1893. Reference: William J. Hammer, "William Wallace and his Contributions to the Electrical Industries."
label: Location
content: Currently not on view
place: label: place made
content: United States: Connecticut, Ansonia
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Coe Brass Manufacturing Co.
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.181640
label: accession number
content: 32363
label: catalog number
content: 181640
objectType: label: Object Name
content: generator
label: Object Name
content: dynamo
physicalDescription: label: Physical Description
content: steel, copper, iron (overall material)
label: Measurements
content: without base: 21 in x 61 in x 18 in; 53.34 cm x 154.94 cm x 45.72 cm