File:Commutator - Advance for Self Induction.png

Summary[edit]

Illustration Description[edit]

Figure 303 -- Commutator brush adjustment for self-induction

• For convenience an electric current is considered to have weight and hence possessing the property of inertia. The current then during commutation cannot be instantly brought to rest and started in the opposite direction, but these changes must be brought about gradually by an opposing force.
• Hence by advancing the brushes beyond the neutral plane as shown in this illustration, commutation takes place with the short-circuited coil cutting the lines of force so as to induce a current in the opposite direction. This opposes the motion of the current in the short circuited coil, brings it to rest, and starts it in the opposite direction, thus preventing sparks at the brush.

Public Domain Source[edit]

• Hawkins Electrical Guide, Volume 1
• Chapter 20: Commutation and the Commutator
• Page 287, Figure 303
• Copyright 1917 by Theo. Audel & Co.
• Printed in the United States

Upload Notes[edit]

• Scanned by User:DMahalko, Dale Mahalko, Gilman, WI, USA -- Email: dmahalko@gmail.com, on 13:42, 20 May 2008 (UTC)
• Scanned at 600dpi, 8-bit grayscale using MicroTek ScanMaker 3600
• Level-adjusted and cleaned up using Gimp 2.4.4

See Also[edit]

For a list of all these illustrations used in Wikipedia please see the article Hawkins Electric Guide on the English Wikipedia.

Licensing[edit]

	This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See this page for further explanation.
	This image might not be in the public domain outside of the United States; this especially applies in the countries and areas that do not apply the rule of the shorter term for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and Switzerland. The creator and year of publication are essential information and must be provided. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.