positive ground?

rob63mess

rob63mess

Well-known member
The guys and I were talking at work last night about my 31 truck. The question came up why was a positive gground used......none of us had an answer......can anyone explain it to us?
 
Skinned Knuckles had an article looking into this a few years ago. As I recall, their conclusion was that there is no good reason to prefer one way or the other. Both positive and negative grounds have been used by a lot of different manufacturers over the years.

At one time, I understood that it had something to do with minimizing corrosion at the connection to the frame, but I now understand that that is bogus.

Just from a physics perspective, it's hard to imagine that the electrons care about which direction they are being asked to travel through an external circuit. It is important that the electrons in the spark plug spark be jumping from the hotter, tip material to the cooler, base material, but that can be arranged well enough with either battery grounding arrangement.

Steve
 
My understanding was that Henry would get a mindset about something and run with it until long after the industry standard had changed, much like he refused to move beyond the Model T and change over to conventional gears, etc. If it weren't for his son, Edsel, there probably wouldn't have been a Model A.

Jack
 
In the early days, they thought electrons flowed from positive to negative, then later they discovered that electron flow is actually negative to positive.
 
modeleh said:
In the early days, they thought electrons flowed from positive to negative, then later they discovered that electron flow is actually negative to positive.
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:confused: But ironically, all of his Model T's, --including his New Improved model (1926-27) were actually Negative ground. :eek:
 
I guess the old codger was ahead of his time on that one, unlike his view of hydraulics. I wonder what convinced them to make the A, positive ground? Maybe it was just beginning to be more popular industry wide, kind of like the old Beta vs VHS thing.
 
If you really want the low-down on electricity, please go to You Tube and type in "Funny Basic Electricity Lecture". About six minutes of some really funny stuff.
 
My 1957 Austin Healey 100-6 has positive ground, or rather "Positive Earth" as the Brits would say.
 
Tom, I hate to be turd:D but polarity(pos or neg ground) does not matter for jumpstarting. Positive to positive and negative to negative is a parallel circuit so voltage does not change.


Just ignore which one is ground and and hook up the way we were taught and it will work. What matters is + and -. Just make sure to get those correct.

Thanks,
Pete
 
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I have worked in the electronics industry for many years, and have never had or found a good explanation for + vs – grounding. Evan in the digital age there was the two schools “active low, and active high”. It really does not matter, it all comes down to standards, the auto industry chose negative ground. Some manufactures took a long time to change, some large truck manufactures were still using positive ground well into the 1980’s. Some heavy equipment manufactures still use positive ground, makes our lives interesting when we try to install electronics / communications equipment in them!
 
rob63mess said:
The guys and I were talking at work last night about my 31 truck. The question came up why was a positive gground used......none of us had an answer......can anyone explain it to us?
Click to expand...

rob,
I've asked everyone that I've spoken with about cars...why positive ground. NO one knows..is the answer. The generator seems to care, if you change vehicle polarity and don't polarize it, oh...and high points builders seem to care:)
 
i read about it in the best book i ever read on the model a."know your model a ford by murray fahnestock". if u can find a copy it is a wealth of information on the A. it is out of print but some time it comes up on ebay,that's where i got my copy.it covers every system on the car and explains why it was designed the way it was. after i read it made the car even more special to me. dennis
 
i heard they switched to negative ground because as the car was moving there would be some electron loss to the moving air/ground similar to static electricity & positive ground would not charge the battery as well when moving due to this loss
 
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