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Reversed battery posts?? Hey Pat, get this!

Afrodesia

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So when we were going to charge the battery the other day, I started to clip the red to red and the black to black. Pat and chris said "no!" (just like that) as battery showed that black was the positive. I told them id done it that way previously but chris started to clip it the other way and it arced. Charger wasn't plugged in but still sparked. pat told us about the way TRs were grounded so it didn't make sense but I proceeded to do it the way I had before (theoretically neg to pos, pos to neg) and it charged fine.

What gives?
 

Geo Hahn

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There is no guarantee that your TR (which was originally positive ground) is still + ground. Many have been converted thru the years to accomodate modern radios and other accessories.

The best way to see what you've got is to look at the battery which should have the posts marked. You can also tell by looking at the post size as the positive post is a larger diameter (I *think*).

So... look at the post that is connected to ground (cable should go from the drivers side battery post to the firewall) and see whhich it is.
 

sp53

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Yes reversed polarity is interesting and is only on DC systems. In another life time full or toil bluff (high school) many American cars were reversed polarity, my 54 ford was that way. Anyway I had this great shop teacher who understood this stuff and I will try and parrot what he said. When looking at cars, it has to do with what direction the spark jumps and the direction in which the electrons vibrate. I think it went like this in a positive ground system the spark jumps off the grounded surface to the new surface and a negative ground system the spark jumps to the surface. Moreover, the spark is whiter on a negative ground as opposed to more blue and has less resistance and delivers more voltage, and for that reason negative systems are better because the spark plug it hotter. I cannot remember why positive ground was used, but there must have been a reason. You can convert yours over to negative ground, but you have to change some stuff by switching the wires and I believe that has to do with the way the internal windings are): the coil, amp gauge, gas gauge and I am sure I missed something.
 

TR3driver

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Actually, the spark remains the same polarity (assuming you've switched the wires as needed), regardless of which side of the battery is grounded.

On a TR3, the full process is to switch the connections at the coil, ammeter and battery. If you have a period-correct radio, it should have a switch or plug to convert to negative ground. Repolarize the generator and you're done. None of the other original parts "cares" about polarity.

If it's an issue for you, though, it might be worth also changing the battery cable to the solenoid to one with red insulation. Personally though, I always look for the marking on the battery and follow that.

Henry Ford was a big believer in positive ground, all Ford cars & trucks were positive until nearly 1960 I believe. Supposedly, he thought it helped reduce electrolytic corrosion of the frame & body. A few other manufacturers also started out positive (like Standard/Triumph, White and Mack. But GM standardized on negative ground fairly early, and the popularity of aftermarket stereos and such more or less forced the rest of the market to follow suit, eventually.
 
OP
A

Afrodesia

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Don't know what in the heck any of that means (but will read repeatedly to figure out) but I can tell you this, the positive clip on the battery charger is connected to the negative post on the battery and vice versa. And it's charging. and it arced when we tried to do it the other way.
 

Geo Hahn

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If by 'arced' you mean there was a little spark when the clip was connected -- that is normal even when the charger is connected correctly.

In fact. that is why you should make the ground connection last and at some point away from the battery (such as the engine block) to lessen the risk that the spark will ignite hydrogen fumes that may be around the top of the battery.

Afrodesia said:
...I can tell you this, the positive clip on the battery charger is connected to the negative post on the battery and vice versa.

I have to say -- if true, that is not so good.
 

TR3driver

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Geo Hahn said:
Afrodesia said:
...I can tell you this, the positive clip on the battery charger is connected to the negative post on the battery and vice versa.

I have to say -- if true, that is not so good.

:iagree:

Just for clarity, you should always connect the positive clip of the charger to the positive post on the battery and vice versa; regardless of how the car is connected to the battery or what color the cables & clamps are.

While it is possible to charge the battery backwards (if it was run flat to begin with), it will quickly ruin the battery.

The only exception that I can think of: Sometimes people put modern batteries inside vintage battery cases, so it looks like they are using a vintage battery. Someone might have done that and mixed up the markings (so it would also look like they were running positive ground when it was really negative).
 

sp53

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Yes I knew a guy once that charged a dead battery backwards and created all kinds of problems before he figured it out. Most batteries have a plus or minus marked on the case so what does that look like. I think you wrong about the polarity spark jumping thing Randal. I read an article some time back about coil polarity and it mentioned the same thing, I think. And if Jack Mc Lin is still alive I am going to tell him what you said, and let him deal with you. There was more to his teaching. He would talk about how some lighting actually travel up from the earth and some did not because of how the static electrons flowed and it had something to do with polarity. Anyways the long and the short of it is, it is most likely time for a new quality battery. They are an essential nutrient for a car.
 

TR3driver

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sp53 said:
I think you wrong about the polarity spark jumping thing Randal. I read an article some time back about coil polarity and it mentioned the same thing, I think. And if Jack Mc Lin is still alive I am going to tell him what you said, and let him deal with you.

Here's a simple test you can try for yourself:
https://mgaguru.com/mgtech/ignition/ig104.htm

As noted, if the flare is towards the wire, then the coil is hooked up backwards. Now switch the way the coil is connected and check to see that the flare goes the other way. It just doesn't matter which side of the battery is connected to ground, the coil can generate sparks with either polarity.

BTW, even the spark polarity doesn't really matter all that much. It takes a bit more voltage to jump the spark the other way, but the coil can easily generate the extra voltage unless something else is wrong. Many cars (and my old motorcycle) actually fire every other plug backwards! (It halves the number of coils you need for a distributorless ignition system.)
 

Geo Hahn

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TR3driver said:
[...It just doesn't matter which side of the battery is connected to ground, the coil can generate sparks with either polarity...

Indeed, an automotive coil can even generate sparks with AC current (I have a working example of this).
 

TR6oldtimer

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Electricity does not care what polarity it is to make a spark. The difference in potential and the resistance it has to overcome is the same. The only difference is in the spark plug design. If the anode and cathode were of the same design, the voltage potential to make the spark would also be the same. Polarity does not matter.

That said, by design the spark plug is what it is, and negative ground works better with the current spark plug design then positive. Whether the selection of positive or negative ground systems was determined by the spark across a spark plug seems dubious to me. The reason is simple. Coil design is what determines the direction of the spark, not the battery. The two are independent of each other. That does not mean Ford did not employ a 'reverse' spark.

As to the battery charging observation, what was happening is the owner was using a hole charger, that is one which use hole-flow.

To clear this up, read this.

https://forum.allaboutcircuits.com/showthread.php?t=1381

If you are not now thourghly confused, you are a rare character.
 

TR3driver

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TR6oldtimer said:
Electricity does not care what polarity it is to make a spark. The difference in potential and the resistance it has to overcome is the same. The only difference is in the spark plug design. If the anode and cathode were of the same design, the voltage potential to make the spark would also be the same. Polarity does not matter.
Sorry, Ray, but I disagree. At least part of the difference is because the center electrode gets much hotter than the ground electrode does. It's easier to break electrons away from the hotter material, hence easier to form a spark when the hotter material is negative. Much the same way a vacuum tube diode works.

diode_vacuum_tube.gif


https://www.radio-electronics.com/info/da...rial-basics.php
 

CJD

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Interesting...

It sounds like you created a negatively grounded car by simply charging the battery backwards! So, are you having issues with the gas gage and ammeter reading backwards? Any charging issues?

John
 

George_H

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Wow, What a topic. tr6oldtimer is correct. "some" of the confusion is the difference between hole flow and electron flow. Electron flow is considered to be flom neg.to pos.and is the flow of free electrons.This is the way most "techs" are taught. Hole flow is the flow of "Holes" (a hole is the space left from an electron that has just broken free from an atom) Most engineers are taught this way.(no wonder they always argue) Randalls vacuum tube is a example of this, Electrons flowing up from the cathode to the anode and the current direction arrow at the top is also pointing to the anode!. If anyone is not confused yet, this should do it. PS I taught electonics for 15Y
 

CJD

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I have never been fast enough to see which way a spark travels. I HAVE accidentally charged a lead-acid battery backwards, though. It actually works, although I cannot say how well it works. It's just interesting to see that on a car a simple as our 3's it will still run after you charge it backwards!! Imagine what it would do to a modern car...

John
 

tomshobby

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Before we get into the world of string theory and it's effect on the common yo-yo has this backwards charged battery been checked with a volt meter? Has the battery been checked under load? Could it be that the charger clips have been put on the wrong leads?
 

TR3driver

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George_H said:
PS I taught electonics for 15Y

And do you really believe there is such a thing as a "hole charger" that gets connected backwards to an "electron charger"? Wow indeed.
 

Geo Hahn

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CJD said:
...I HAVE accidentally charged a lead-acid battery backwards, though. It actually works...

As some academic famously said "It works in practice, but does it work in theory?".

When I took delivery of my TR4 the PO had installed a new battery -- backwards. Everything worked fine and I only noticed the error once I started checking details. Yes, the ammeter worked backwards but that didn't catch my attention as TR4 ammeters are the opposite of TR3 ammeters anyway (discharge moves the late-TR4 needle right).
 

TR6oldtimer

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TR3driver said:
TR6oldtimer said:
Electricity does not care what polarity it is to make a spark. The difference in potential and the resistance it has to overcome is the same. The only difference is in the spark plug design. If the anode and cathode were of the same design, the voltage potential to make the spark would also be the same. Polarity does not matter.
Sorry, Ray, but I disagree. At least part of the difference is because the center electrode gets much hotter than the ground electrode does. It's easier to break electrons away from the hotter material, hence easier to form a spark when the hotter material is negative. Much the same way a vacuum tube diode works.

diode_vacuum_tube.gif


https://www.radio-electronics.com/info/da...rial-basics.php
You have made my point. Electricity does not care which way a charge is placed on two IDENTICAL plates. However, a bias can certainly be created by the design of the device. The vacuum tube is an example of this applied bias, that is the cathode is purposely heated to facilitate the release of electrons by exciting the metal and their electrons to a higher energy state, thus reducing the voltage differential needed to free them.

Now whether the anode or the cathode of a spark plug is designed with the same consideration in mind, that is to enhance the flow of electrons, I can not say with authority. It may be just an artifact of the way a spark plug is designed to accommodate the violent environment it must endure.

Oh, on lead acid batteries, yes they can be charged backwards, although as in the example of the vacuum tube, their design bias will probably reduce their efficiency if one were to do that.

Now on the topic of what is current, the one that I really have a difficult time getting my hands around is the theory of protons as current. Unlike electrons, protons are tightly bound in the nucleus of the atom. The binding energy of the nucleons is tremendous when compared to the electrical attraction of an electron to the nucleus. To understand how strong the binding force is, one only needs to consider what it takes to keep two positively charged nucleons in close proximity to each other.

The notion of free protons implies to me, there must be for some period of time an atom that has changed it's atomic structure and during that brief time the binding energy of the nucleon is released. Then to return to it's original atomic structure, the same energy would need to be applied when replacing the 'lost' proton. I suppose this phenomena could occur in such a small time frame that any energy released when a proton is kicked free is immediately applied to bind another.

Like I said, it is a concept I do not have the physics to comprehend.
 
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