Stranded or Solid????

[blackkarma]

Well ive decided to put together my own engine harness. I started mapping out my setup and materials that i plan to use but ive ran into a issue which ive been going back and forth about all day.

heres my problem:

i want to know why noone uses sold wire over stranded when it comes to the signal wires in the vehicle. now i know many people would say that stranded wire is used because of its flexablity but from what ive seen sold wire is now just as flexable as any stranded wire you can pick up. a solid coax wire would out perform a stranded wire when it comes to holding a signal so why havnt things changed in all these years. i found out while making the harness for my standalone that most of the signal wires in our vehicle can barely hold or carry a constant or stable signal. our stock ecu seems to be able to deal with the low signal quality but these new ems and piggyback systems seem to be having trouble. all in all i just want an explaination for the stranded wire over solid, why is everyone but the automotive community using it?

 

[Poodles]

You are correct, you don't use solid core in a high vibration environment.

 

[EOS]

Somebody correct me if I’m wrong, but here’s what I know regarding the situation: solid core wire is generally used in an AC electrical system, whereas stranded wire is used in a DC electrical system. The reason for this isn’t because of additional flexibility with a stranded wire, but rather the way the current is carried through the wire. Solid core wire used in an AC electrical system uses the entire cross section of the wire, while a DC electrical system uses only the outside surface of the wire, not the entire cross section of the wire. Therefore, the more strands that are in a stranded wire, the more efficiently the wire carries the power to a given component due to more surface area. In the past, in the RC car field, there was a type of 13 gauge wire (called Super 13, I think) that had, if I remember right, about 1400 strands in it for just this reason. This is in addition to what poodles said regarding vibration resistance with solid core wire.

I definitely don’t wish to give out any incorrect information, so feel free to correct me if you think I’m wrong, but this was the case as I remember it.

Hope this helps…
Joe