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Description: | LORD KELVIN'S PATENTS, TESTING SET No. 287 KELVIN & JAMES WHITE LTD GLASGOW & LONDON,
50,000 OHMS AT 18'C (engraved on the galvanometer casing). 759 GALVANOMETER KELVIN (BT number engraved on a brass placque on the box) MANU James White. between 1904 and 1914 16,18,20 Cambridge, Street, Glasgow, Scotland DES THOMSON,William,Lord,1st Baron Kelvin of Largs. after 1888 DES after SCHWEIGGER,Johann,Salomo,Christoph. 1820 Halle, Germany. This tangent galvanometer is from a high voltage test set probably used for testing insulation.
This electrical testing set that was generally used for testing circuit continuity. It was designed for use in industrial engine rooms and power stations but was found useful in various situations. The instrument is called a tangent galvanometer because the voltage in the circuit under test is proportional to the tangent of the angle of deflection of the needle.
Galvanometers are instruments which measure voltage. This type of instrument has a small magnet free to rotate at the centre of a coil of fine copper wire. When the instrument is connected to an electrical circuit the magnet is affected by the flow of electricity in the coil which causes the needle of the instrument to deflect.
This instrument is a development of a prototype test instrument see GLAHM 113329. Lord Kelvin designed it for the early electrical industry. In 1881 his official residence, at No 11 Professor's Square at the University of Glasgow, was the first house in the world to be entirely lit with incandescent electric lamps.
N.B. This instrument, has a set of shunts to alter its range, and has a pair of adjustable correcting magnets that compensated for the Earth's magnetic field so that the magnetometer could be zeroed in any position. | License: | http://www.hmag.gla.ac.uk/spirit/rights/ | Publisher: | Hunterian Museum and Art Gallery, University of Glasgow | Rights holder: | Hunterian Museum and Art Gallery, University of Glasgow | Subjects: | SCIENTIFIC COLLECTION : | Source: | Hunterian Museum | Creator: | Hunterian Museum and Art Gallery, University of Glasgow | Identifier: | http://www.huntsearch.gla.ac.uk/cgi-bin/... | Language: | en-GB | Go to resource |
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