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[N220015], Technical Note, Charles Lorenzo Clarke, August 15th, 1881

Title: [N220015], Technical Note, Charles Lorenzo Clarke, August 15th, 1881
Editor's Notes: "C No. 2. London dynamo. The length is increased from 33.75 to 44.5 over C No. 1 for Paris. This gives an increase of 32% in EMF effficiency. The two extra magnets added to C No 1 gave an increaes of 20% efrficiency and 4 extra magnets would increase this efficiency 40%. This 40% gain wil be upon a length of 33.75 for armature. The total gain will therefore be 72%." This means can reduce number of commutators from 73 to 53 and 106 bars, taking into account some efficiency losses for increasing spacing btwn armature and pole pieces. Calculates armature resistance as 0.00388 ohms; for load of 1200 lamps of 140 ohms each (in //) gives load resistance of 0.1167 ohms; this yields a ratio of internal to external resistance of 1-30. "1200 lamps will be 120 Electrical H.P. which will require the loss of 4 H.P. in armature." In another calc he derives ratio of internal to external resistance as 1 to 36.5.
Author: Clarke, Charles Lorenzo
Date: 1881-08-15
Type: Technical Note
Subject: Dynamos and generators
Folder ID: N220-F
Microfilm ID: 41:6
Document ID: N220015
URL: https://edisondigital.rutgers.edu/document/N220015
Rights: Thomas Edison National Historical Park
Publisher: Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University
Has Version: Archive.org Viewer, Microfilm Series Reel 41
License: CC0 1.0 Universal

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