File:National Bureau of Standards high voltage laboratory.png
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Summary[edit]
DescriptionNational Bureau of Standards high voltage laboratory.png |
English: High voltage laboratory at the U.S. National Bureau of Standards, Washington DC, USA, in 1948. The caption of the image in the source is: "A special 6-story laboratory at the Bureau houses a 1,400,000 volt x-ray generator (rear) and a 1,050,000 volt cascade transformer (foreground). The latter is used for testing and calibrating commercial power equipment as well as for producing simulated lightning, used in investigating protective measures in installations and aircraft." The cascade transformer is shown in operation, producing a long electric spark. The luminous glow visible on the wires carrying the high voltage is called corona discharge, and is caused by electricity leaking into the air. The cascade transformer in the black column (right) that generates the high voltage consists of several transformers connected in cascade, with each successive transformer at the secondary potential of the previous one, so no single transformer winding will have to withstand the full output voltage. |
Date | |
Source | Downloaded 2012-01-24 from E. U. Condon, (1949) Annual Report of the National Bureau of Standards for 1948, U.S. Government Printing Office, Washington DC. USA, p. xiv on Google Books |
Author | Unknown authorUnknown author |
Licensing[edit]
Public domainPublic domainfalsefalse |
This work is in the public domain in the United States because it is a work prepared by an officer or employee of the United States Government as part of that person’s official duties under the terms of Title 17, Chapter 1, Section 105 of the US Code.
Note: This only applies to original works of the Federal Government and not to the work of any individual U.S. state, territory, commonwealth, county, municipality, or any other subdivision. This template also does not apply to postage stamp designs published by the United States Postal Service since 1978. (See § 313.6(C)(1) of Compendium of U.S. Copyright Office Practices). It also does not apply to certain US coins; see The US Mint Terms of Use.
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This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights. |
https://creativecommons.org/publicdomain/mark/1.0/PDMCreative Commons Public Domain Mark 1.0falsefalse
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current | 07:32, 26 January 2012 | 810 × 1,275 (847 KB) | Chetvorno (talk | contribs) |
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File change date and time | 06:53, 26 January 2012 |