Positive Ground

[verrece]

Two questions
Does anybody knows why Ford was chosen the positive battery grounded?
and why they switched to negative grounded after?

[MikeK]

The jury was out as to which ground polarity caused less corrosion. (It still is!!) The "T" was neg, the "A" pos, then later back to neg. Way back in the T era it was thought electricity flowed from the pos to neg. The opposite is true.

[Terry, NJ]

I once heard a convoluted electrical explanation that agreed with with what Mike wrote. It had to do with the flow of ions (I don't speak electric). But Ford and Chrysler both used a + ground. I don't know what year Chrysler switched, but Ford's last year with a 6V, + ground was 1955.
Terry

[steve s]

Here's a little dissertation I wrote on that topic a while back for our club newsletter.

Why Negative Ground?

A recent forum discussion thread on the fordbarn.com web site motivated me to go back and look again at an article in the Skinned Knuckles magazine. The article, "Why Negative Ground?" was in the September 2009 issue, #398. The simple question about a relatively modern occurrence was asked by a reader: Why did all remaining positive-ground U.S. manufacturers switch to negative-ground in 1956? After extensive research seeking an answer, the frustrated editor concludes,

"Much as I would like to announce that we have an answer, unfortunately just the opposite is true. Not only have I not obtained facts, but I am also puzzled beyond belief that the wide variety of automotive historians and curators whom I questioned could not come with a factual answer."

One U.K. electrical engineer and museum curator who was queried on the subject replied, "You have opened a can of worms..."

The SK article includes a table showing ground usage by 35 car models since 1932. Twenty five of those used positive ground for at least part of their existence. The various models that became part of GM, except for Cadillac, always used negative ground, as did Duesenberg, Essex, Stutz, and Reo. Cadillac switched from positive to negative ground after WWII. Hudson switched from negative to positive ground in 1934, and then back to negative in 1956. The "universal" switch to negative ground never occurred in the U.K. Nash Metropolitans remained positive ground, and allegedly some US car models made for export to the U.K. are still set up with positive ground.

The various creative, speculative or bogus rationales supporting one or the other grounding usage that have been offered over the years, including the corrosion thing, are briefly reviewed. The fact is that in 1956 there was a sudden consensus that it would be a good idea to standardize, but exactly how and why that consensus emerged at that moment in time remains puzzlingly mysterious.

I think it's clear that there really is no strong argument to be made one way or the other, but standardization is a good idea, and, happily, it came to pass! Too bad Ford was on the wrong side of history, but it's no big deal.

Steve Schullery

[MrTube]

One thing I would like to point out to those who do not understand electricity. All circuits need two connections. In the case of DC as it is in the model A you have a positive and a negative. You could run two wires to everything and not connect to the car's chassis, but this would cost more money and labor. Another option is to use the car's chassis as one of these connections and when done this way it is commonly called "chassis ground". In reality it has nothing to do with ground (earth) it is simply called this just as the capacitor in the igntion system is called a condenser in the automotive world. Another example is generator vs alternator. An alternator is a type of generator and only in the automotive world is it called "an alternator".


My beleive, is it doesn't matter which is connected via the car's chassis, negative or positive and everyone just wanted to standardize in the 50s.

[steve s]

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Originally Posted by MikeK

...Way back in the T era it was thought electricity flowed from the pos to neg. The opposite is true.

It's still true that the physicist's definition of the direction of current flow is the direction positive charge travels. Since in metal wiring, it is the negatively charged electrons that are actually traveling, the direction of the current (as far as physics conventions go) is the opposite direction to that in which the electrons are moving.

[Roadster62]

I think the main reason I'll never understand electricity is the fact that no two people can supply the same answer to an electrical question. Bob

[MrTube]

Originally Posted by Roadster62

I think the main reason I'll never understand electricity is the fact that no two people can supply the same answer to an electrical question. Bob

Electron flow = Neg to Pos. Hole flow = Pos to Neg.

In reality it doesnt matter, all that matters is that everyone agrees on one system. Solid state schematic symbols are technically backwards, but everyone understands what they mean.

In a vacuum tube electrons "boil off" of the heated negative charged cathode and are attracted to the positive charged plate. I believe this is when they realized electrons flowed neg to pos.


All a car mechanic needs to know is if the POS of the battery is connected to the chassis of the car, then all of the stuff installed in the car needs its POS lead connected to the chassis.

What will really bake your noodle is electrons don't flow down a wire like water through a pipe. They kinda move around and move in that general direction but some may never leave the wire.

Here is an analogy I found on a website a while back regarding AC current flow (not related to cars) and I thought it was really good.

This doesn't really have anything to do with saving electricity but it gives me an excuse to use an analogy I came up with.
Anyway, pretend a giant is sitting in the yard at the power plant. Or it can be Shrek if you prefer, whatever. Also pretend that instead of electrical wire, we use dental floss. The giant is holding a piece of dental floss in one hand, and that leads to your house, through your house, then back out to the power plant and into the giant's other hand. So you've got a giant holding an enormous strand of dental floss that forms a complete loop, starting in one hand and ending in the other. With me so far? Good.
Okay, so now the giant pulls on one end of the floss. As he does that one hand comes towards him and the other goes away from him. Then he pulls on the other end to do the opposite. Pretend he's exercising with the floss. He does this really fast, reversing direction 120 times per second, or 60 times per second if you count doing both directions as one set.
That's how household AC electricity works. It doesn't start at the power plant, run through your house, and then go back to the power plant. Instead what's happening is the power plant is pushing electrons down one end of the wire, then they reverse it and push from the other end. The electrons in the wire get rubbed back and forth, like a scrub brush. This is what transfers energy to the appliances you're running.

[BILL WILLIAMSON]

Originally Posted by steve s

It's still true that the physicist's definition of the direction of current flow is the direction positive charge travels. Since in metal wiring, it is the negatively charged electrons that are actually traveling, the direction of the current (as far as physics conventions go) is the opposite direction to that in which the electrons are moving.

steve s,
Chief taught me about those "little men" that ran only in one direction inside the wires making electrical stuff operate. He said they ran from positive to negative.
So, now you mess up my larnin' with the PHYSICIST'S defininition! Are there two different groups of "little men," each runnin' in different directions?? How do you tell them apart?? Are they different colors, or does one group wear "little beards," or different uniforms??
Chief puzzled me once by changing one old Model A to negative ground! He only had to switch the ammeter wires, switched the coil wires & re-polarized the generator! My head was all messed up for 3 days!
I worry a lot about small details, like, does this China made coil have it's + and - terminals marked properly, or was something "lost" in the design translation?
I hope I can sleep tonight, after reading this thread. Hope the dog remembers my shrink's phone number! Bill W.

[ctlikon0712]

Could Fords changes have had anything to do with his friend Mr. Edison? Or could the change from T to A have had something to do with Edsel? He had much more to do with the design of the A and Henry had less. Also What year did Edsel bow out of running Ford Mo. Co.?

[Roadster62]

I can't understand the one hand coming twards him and the other going away, what is happening to the dental floss? When I floss both hands move in the same direction. Bob

Originally Posted by MrTube

Electron flow = Neg to Pos. Hole flow = Pos to Neg.

In reality it doesnt matter, all that matters is that everyone agrees on one system. Solid state schematic symbols are technically backwards, but everyone understands what they mean.

In a vacuum tube electrons "boil off" of the heated negative charged cathode and are attracted to the positive charged plate. I believe this is when they realized electrons flowed neg to pos.


All a car mechanic needs to know is if the POS of the battery is connected to the chassis of the car, then all of the stuff installed in the car needs its POS lead connected to the chassis.

What will really bake your noodle is electrons don't flow down a wire like water through a pipe. They kinda move around and move in that general direction but some may never leave the wire.

Here is an analogy I found on a website a while back regarding AC current flow (not related to cars) and I thought it was really good.

This doesn't really have anything to do with saving electricity but it gives me an excuse to use an analogy I came up with.
Anyway, pretend a giant is sitting in the yard at the power plant. Or it can be Shrek if you prefer, whatever. Also pretend that instead of electrical wire, we use dental floss. The giant is holding a piece of dental floss in one hand, and that leads to your house, through your house, then back out to the power plant and into the giant's other hand. So you've got a giant holding an enormous strand of dental floss that forms a complete loop, starting in one hand and ending in the other. With me so far? Good.
Okay, so now the giant pulls on one end of the floss. As he does that one hand comes towards him and the other goes away from him. Then he pulls on the other end to do the opposite. Pretend he's exercising with the floss. He does this really fast, reversing direction 120 times per second, or 60 times per second if you count doing both directions as one set.
That's how household AC electricity works. It doesn't start at the power plant, run through your house, and then go back to the power plant. Instead what's happening is the power plant is pushing electrons down one end of the wire, then they reverse it and push from the other end. The electrons in the wire get rubbed back and forth, like a scrub brush. This is what transfers energy to the appliances you're running.

[Roadster62]

Maybe the fact that the T has a magneto has something to do with it. Bob

Originally Posted by ctlikon0712

Could Fords changes have had anything to do with his friend Mr. Edison? Or could the change from T to A have had something to do with Edsel? He had much more to do with the design of the A and Henry had less. Also What year did Edsel bow out of running Ford Mo. Co.?

[MrTube]

Originally Posted by Roadster62

I can't understand the one hand coming twards him and the other going away, what is happening to the dental floss? When I floss both hands move in the same direction. Bob

Picture rapping a rope around a tree and pulling it back and forth, as you pull with one hand the rope will pull your other hand away from you and towards the tree.

[Napa Skip]

Edsel Ford was president of Ford Motor Company from 1919 until he died on May 26, 1943.

[Mike V. Florida]

Originally Posted by MrTube

Electron flow = Neg to Pos. Hole flow = Pos to Neg.

All the symbols in electronics are logically drawn for Pos to Neg with current flowing in the direction of the arrows.

[Jim/GA]

Here is one observation I hage made over the years with my 6 volt POS ground Model A:

When I disconnect the POS ground cable from the battery when I store a car for an extended period of time, to prevent any stray current drain on the battery and to prevent an electrical fire, I often come back to a find corrosion on the starter cable that is still connected to the NEG battery post.

I never find this corrosion on my NEG ground cars when I leave them with the ground cable disconnected for extended periods.

This is the only advantage I have ever seen with a NEG ground setup.

[Ca. Kid]

Positive ground depends upon proper circuit functioning, the transmission of negative ions by retention of the visible spectral manifestation known as "smoke". Smoke is the thing that makes electrical circuits work; we know this to be true because every time one lets the smoke out of the electrical system, it stops working. This can be verified repeatedly through empirical testing.

[Roadster62]

OK, I understand that, but I've never rapped dental floss around a tooth that way. Sort of proves my point about no two electrical answers being the same........even worse two different explanations from the same guy! Bob

Originally Posted by MrTube

Picture rapping a rope around a tree and pulling it back and forth, as you pull with one hand the rope will pull your other hand away from you and towards the tree.

[MrTube]

Originally Posted by Roadster62

OK, I understand that, but I've never rapped dental floss around a tooth that way. Sort of proves my point about no two electrical answers being the same........even worse two different explanations from the same guy! Bob

Eh... I tried.

[steve s]

Originally Posted by BILL WILLIAMSON

steve s,
Chief taught me about those "little men" that ran only in one direction inside the wires making electrical stuff operate. He said they ran from positive to negative. ....

Sorry, Bill, but Chief told you wrong; the "little men" in wires are negatively charged electrons, and they will run from negative to positive, just like you'd expect from the "opposites attract" rule.

The people who developed the equations that describe electrical and magnetic forces had to decide on a convention for how to put a mathematical positive or negative sign on electric current (i.e., flow of charged particles). Current flowing in the direction that positive charge would move is given the positive sign; a current of negative charge flowing in the opposite direction also has a positive sign.

In other words, for physics calculation purposes, the "current" in wires is described as flowing in the opposite direction that the actual charges (electrons) are moving. They could have done it the other way, but no one now wants to go back and change all the signs in the E&M equations. Some blame Benjamin Franklin.

A lot of complexity could be avoided if the only kind of electricity the world had to deal with was electrons moving in wires. But, the equations have to also work for things like both positive and negative ions moving in solutions and plasmas, and "positive holes" moving in semiconductors, in which cases, it is sort of like different kinds of little men moving in different directions.

Steve