Quote:
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Originally Posted by Tom Bottiglieri
By the way, you would be much better off using thick stranded wire than one solid piece of wire. Current flows on the surface of a conductor, so the amount of current a single piece of wire can transmit is limited by its size.
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Only the alternating component of electrical current tends to concentrate on the surface of a conductor. This is often called the
skin effect. The effective depth to which current penetrates into the interior is inversely proportional to the square-root of the frequency at which the current alternates, so higher frequency current tends to concentrate on the surface, while dc is uniformly distributed over the cross-section of the conductor.
Since only a small component of the motor current in a FIRST robot is ac (due to the pulse-width modulation of the Victors), using stranded wire does not improve the current carrying capacity significantly over that of solid conductors with the same total cross section; i.e., the same AWG.
However, using stranded wire is still a good idea because it is less prone to damage from bending and flexing, and it forms better electrical connections when crimped to standard terminals.
__________________
Richard Wallace
Mentor since 2011 for FRC 3620 Average Joes (St. Joseph, Michigan)
Mentor 2002-10 for FRC 931 Perpetual Chaos (St. Louis, Missouri)
since 2003
I believe in intuition and inspiration. Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution. It is, strictly speaking, a real factor in scientific research.
(Cosmic Religion : With Other Opinions and Aphorisms (1931) by Albert Einstein, p. 97)