mack73 Wrote:
>
> Well not really. The risk is the same if the
> switch was on the + or -
>
> Since the voltage needs to flow in a circle,
> disrupting the path at any point (before or after
> the device) will result in the same event
> (electrons can't get from the + post on the
> battery to the - post on the battery). The only
> difference is where the electrons are held up: at
> the + switch or you guessed it, at the - switch.
>
>
>
> So in your example: if switching positive, but the
> battery were to flop around and the + post or the
> wire leading from the battery to the master switch
> came in contact with the body = sparks of fun.
>
> If the switch was on the negative and the battery
> were to flop around and the - post or the wire
> leading from the ground switch to the battery came
> in contact with the body = sparks of fun.
>
> I understand what your getting at but if the -
> battery cable was removed from the battery and you
> touched a positive cable from the battery to the
> car, you don't get any sparks do you?
>
> So which battery cable do you take off first when
> removing a battery
>
> 94 Golf
> www.Mack73.com
>
>
>
> Edited 1 times. Last edit at Mar 3, 2009 by
> mack73.
This is wrong. Electrons flow from the negative terminal of the battery to the positive terminal on the battery. Electrons are negatively charged. The reason the positive sparks is that steel and may other materials for that matter have lots of extra or weakly retained electrons that are basically getting sucked out of the material by the positive source. Causing the spark to jump from the negative to the positive.
The reason the negative does not spark is that both sides have plenty of electrons so there is nothing that is motivating them to start flowing.
You are right in my setup if that battery flops around there will be sparks to the battery or the lead that goes to the switch from whatever started touching it. But the sparks will be limited to the battery and cable that comes form the lead since the switch is preventing the rest of the system from seeing the + attraction of the battery.
In the switched negative situation if the battery flops around. You can now get sparks in every circuit since the + is trying to pull electrons from everywhere. So all circuits could have electrons flowing down them and thus the whole harness becomes a fire hazard.
Edited 1 time(s). Last edit at 03/05/2009 12:16PM by Andrew_Frick.
