plug-type galvanometer shunt
Datelate 19th-early 20th Century
Inventory Number0372
ClassificationGalvanometer Shunt
Subject
Maker
Electric Manufacturing Company
1884 - 1930s ?
Cultural Region
Place of Origin
Dimensions13.4 × 11 × 11 cm (5 1/4 × 4 5/16 × 4 5/16 in.)
Material
DescriptionFrom card: "A universal type galvanometer shunt. Two heavy binding posts and four plug positions arranged on a circular hard rubber cap. Three resistance spools mounted on the underside of this cap and fitted to a brass cylinder with a similar bottom of hard rubber. Physics Blue triangle indicates use in Physics 3 in the late 1920's
When connected in parallel with a galvanometer the four positions of the plug are; ("open") galv reads full scale; "1/9" equivalent to 1/10 full scale; 1/99 equivalent to 1/100th and 1/999 to 1/1000 and "short" circuited or 0. There are three spools with probably manganin wire for the proper shunt resistances.
When connected in parallel with a galvanometer the four positions of the plug are; ("open") galv reads full scale; "1/9" equivalent to 1/10 full scale; 1/99 equivalent to 1/100th and 1/999 to 1/1000 and "short" circuited or 0. There are three spools with probably manganin wire for the proper shunt resistances.
Signedtop marked: Electric Mfg. Co. Troy, N.Y.
Inscribedtop marked: Electric Mfg. Co. Troy, N.Y.
FunctionGalvanometer shunts are used to increase the range of a galvanometer.
If too much current flows through a Galvanometer, the needle will reach the end of the scale, and the inner circuits may be burned. To prevent this and to extend the range of a galvanometer, one uses a shunt, which provides an alternative path for most of the current to flow through. Depending on the selected setting on the shunt, one then needs to multiply the readings of the galvanometer by a factor.
If too much current flows through a Galvanometer, the needle will reach the end of the scale, and the inner circuits may be burned. To prevent this and to extend the range of a galvanometer, one uses a shunt, which provides an alternative path for most of the current to flow through. Depending on the selected setting on the shunt, one then needs to multiply the readings of the galvanometer by a factor.
ProvenanceFrom the Harvard Physics Department. Blue triangle indicates use in Physics 3 in the late 1920's.
Hartmann & Braun AG
Date: 1900-1920
Accessories: plugs (8)
Object number: 1997-1-0399
Siemens & Halske AG
Date: circa 1900
Object number: 0275a,b
Siemens & Halske AG
Date: circa 1910
Accessories: seven shunts (0560b-h)
Object number: 0560a
Leeds & Northrup Company
Date: 1926-1929
Accessories: storage box
Object number: 1997-1-0227f