DCC BUSS, Stranded VS Solid?

[Anonymous]

In one of these threads, somebody stated they had "incorrectly" used solid 12 gauge wire for buss wires in their DCC installation. I don't understand how stranded would be preferable over solid core. Somebody, please "enlighten" me?

[cacole]

It really doesn't matter as long as the gauge of the wire is sufficient to carry the necessary voltage/amperage, normally 14 volts at up to 4 or 5 amps. The main thing to consider is how to fasten other wires to it. In some respects stranded is easier to use than solid because it is more flexible and can carry more current with a smaller diameter wire. Electrical current does not flow IN a wire, it flows on the surface of the wire, so a larger diameter wire has more surface on which electronics can flow. Sixteen strands of small wire twisted together to form the equivalent diameter of a 14 gauge solid wire, for example, have more surface for electronics to travel on than the solid wire, so stranded wire can carry more current. A 14 gauge AWG solid copper wire is rated at 5.8 amps at 110 volts AC current carrying capacity. With DC (and DCC) at 14 volts, a 14 gauge wire should be able to carry up to 10 amps. The poster of the message you refer to may have encountered an electrical overload problem with the solid wire, but it's more likely that he just found it difficult to bend and work with.

[ClinchValleySD40]

Only reason to use stranded over solid is ease of installing. Much easier to pull stranded around the layout, especially on the thicker guage.

[Anonymous]

cacole,
I have been under the impression that solid wire handles more current than stranded. However, this is likely moot with 12 gauge wire, at the amperage requirements needed for this application.

[mls1621]

Deschane,

You are correct, solid wire can handle more amperage than stranded wire of the same gauge. 12 gauge solid wire has less resistance than 12 gauge stranded wire.

Current does travel through the wire not on the surface, it's like water through a pipe.

And just as water, one big pipe can handle more water than a bunch of small pipes in the same physical space.

Unless you have a situation that requires flexability, solid wire is the best conductor.

[nfmisso]

QUOTE: Originally posted by mls1621

Current does travel through the wire not on the surface, it's like water through a pipe.

Hi Mike;

This correct at DC and low frequencies, as the frequency gets higher, there is less conduction in the center. DCC is considered low frequency in this situation.

Bottom line for DC, DCC and AC on your layout, use which ever suits your needs and wants best.