Battery jumper cables and terminolgy of CCA

MrWizard wrote:
"Skin effect" As it is called is a, special situation with extremely high voltage

Actually HIGH FREQUENCY more so than high voltage.

Skin effect is not at play at DC or even low frequency AC only becomes an issue when you are playing around with RF frequencies as in radio transmission or broadcast (although skin effect starts to happen at low frequency AC typically no special measures are normally needed to deal with it).

I found a very good explanation from Beldon Wire HERE which has a rather nice write up.

Here is a short quote from the above website..

"Skin Effect happens in all wire and cable (or in any metal object that conducts a signal, such as a trace on a circuit board or antennas, etc.). When the "signal" is DC, it uses the entire conductor, with the same amount of current flowing in the center of each wire as on the outside of the wire. As the signal changes frequency (i.e. is now a wave changing direction) a very odd effect occurs: the signal begins to move more to the outside of the conductor than the inside. For audio frequencies, which are pretty low frequencies in the spectrum, this effect is so tiny it can barely be measured. Table 1 below shows how much conductor is used at 20 kHz, pretty much the highest audible frequency, and compares that to various wire sizes. "

I would highly recommend folks to look at the above website and read the entire article.

As far as the jumper cable the OP bought, under normal circumstances it will most likely be fine for jump starting a small vehicle engine but if dealing with a bigger V8 or Diesel I would opt for a heavier set of 100% copper cables..

The copper coating is simply not heavy enough to overcome the weaker aluminum. You have to step up several gauge sizes in aluminum to get the same current capacity as 100% copper.