Originally posted by wayner:
Thanks Hank, But if a starter is dragging and drawing excessive current there maybe a voltage drop regardless of the wire resistence?
Yes sir, right again. No matter what size wire or it's length it can happen. Now consider this, the 1 gauge 1 ft wire is virtually 0 ohm's, no resistance, not really but close enough. It's not until the starter shorts internally and approaches 0 ohms, no resistance, that the wire becomes a factor. As long as the starter has some resistance the amount represented by the wire is small in comparison. Example, no bearing on this situation just easy numbers to use for an example.
The starter has a resistance of 1 ohm. The wire has a resistance of .01 ohms. That’s a 100 to 1 ratio. Since the total current drop is always 12v all you have to do is divide it up between the 2 parts. The wire will drop ~ .12v and the starter will drop ~ 11.88v.
So let’s say the starter shorts, now the wire becomes a factor. At this point it doesn’t make much difference if that other wire is at one end of the big battery cable or the other. The amount of load it adds is insignificant compared to the shorted starter.
Again I hope may explanation was understandable. I understand it but I make a losey teacher.