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View Full Version : Reversed battery posts?? Hey Pat, get this!



Afrodesia
08-25-2012, 12:36 PM
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?

DNK
08-25-2012, 12:47 PM
Bass Ackward Electrons

Geo Hahn
08-25-2012, 01:24 PM
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
08-25-2012, 01:25 PM
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
08-25-2012, 01:57 PM
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.

Afrodesia
08-25-2012, 04:58 PM
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
08-25-2012, 05:04 PM
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.


...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
08-25-2012, 05:06 PM
...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
08-25-2012, 07:59 PM
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
08-25-2012, 08:29 PM
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
08-25-2012, 08:50 PM
[...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
08-25-2012, 11:20 PM
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
08-26-2012, 01:10 AM
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.

https://www.radio-electronics.com/info/data/thermionic-valves/vacuum-tube-theory/diode_vacuum_tube.gif

https://www.radio-electronics.com/info/da...rial-basics.php (https://www.radio-electronics.com/info/data/thermionic-valves/vacuum-tube-theory/tube-tutorial-basics.php)

CJD
08-26-2012, 08:17 AM
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
08-26-2012, 08:41 AM
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
08-26-2012, 08:55 AM
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
08-26-2012, 09:15 AM
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
08-26-2012, 09:33 AM
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
08-26-2012, 11:32 AM
...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
08-26-2012, 12:11 PM
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.

https://www.radio-electronics.com/info/data/thermionic-valves/vacuum-tube-theory/diode_vacuum_tube.gif

https://www.radio-electronics.com/info/da...rial-basics.php (https://www.radio-electronics.com/info/data/thermionic-valves/vacuum-tube-theory/tube-tutorial-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.

TR3driver
08-26-2012, 01:39 PM
However, a bias can certainly be created by the design of the device.
Yeah, OK, I guess you can call the electrode temperature part of the design of the spark plug. But it is a more or less inevitable part of the design, since the center electrode must be insulated from ground and electrical insulators are also thermal insulators. Definitely not intentional, at least not originally.

As far as hole flow, as I understand it only the "holes" move, not the protons (which are, as you say, tightly bound). It's kind of like a game of Chinese checkers, where the marbles are the electrons and the holes are in the board are the protons. As you jump your marble along left to right, the empty hole "moves" right to left even though the board doesn't change.

But the important bit, IMO, is that <span style="font-weight: bold"><span style="text-decoration: underline">it really doesn't matter</span></span>. For any practical use (like wiring a car), just follow one convention or the other and let it go at that. If you view electrical current as "flowing" from positive to negative, it all works out. If you prefer to think of electrons going the other way, it still works out.

Similarly, I don't have to know if the light is particles or waves in order to use a light bulb. And I can set my watch without taking into account the relativistic contraction.

Geo Hahn
08-26-2012, 01:58 PM
What time does this episode of Nova end and Car Talk come on? :wink:

Afrodesia
08-26-2012, 02:32 PM
I reversed it in the first place because of they way I saw the grounding. I didn't know it was grounded differently than more modern cars. Also, when it was pointed out that I had reversed it &amp; we swapped, the charger needle jumped around about every 10 seconds. Seemed really odd.

So at this point, what will happen if I charge it according to the recommended (not reversed) way? Will it further damage the battery?

CJD
08-26-2012, 05:29 PM
Hey Afro...to get to your point...!?!

You will first have to discharge the battery, so you start at stone dead. Just leave the headlights on for a few hours after they kill the battery. Then hook up the charger correctly and let it charge. You may have 2 issues, well make it 3:

1) Some modern chargers are sensetive to polarity, so they may not allow you to fix the reverse. The solution to that is to use jumper cables from another car for just 30 seconds or so (after the complete discharge, of course). The charger should then work fine.

2) The generator may need to be re-polarized. I would probably do it as a matter of course before you try to run the car after the charge. Moss has a good video showing how to do it, and it only takes a minute.

3) Do not be surprised if the battery won't hold a charge after this. Deep cycle batteries have a lot of lead and are designed to be abused. Most modern batteries have very thin lead plates...that tend to distort and short when abused. So don't chase your tail too much if the battery doesn't seem to hold a charge.

Anyway, you are very lucky...as this has to be one of the few cars you can run backwards and not damage anything! And don't worry, you are not the first to do it.

Good luck,

John

PS...to get in on the spark debate. The other day we were cruising in a high overhang at 35k feet and started picking up St. Elmo's fire. It was beautiful, blue arcs extending at least 12 feet forward off the nose of the plane. I pulled out my camera to take a pic, but all of a sudden a lightening bolt discharged right through the nosecone. It jarred the plane so hard that every single passenger felt the huge thud and saw the bright flash. They all were scared pale and asked about it after we landed.

So...which way was the electron flow for that spark? Or was it the "hole" in the nosecone being filled?

LOL

TR6oldtimer
08-26-2012, 08:13 PM
PS...to get in on the spark debate. The other day we were cruising in a high overhang at 35k feet and started picking up St. Elmo's fire. It was beautiful, blue arcs extending at least 12 feet forward off the nose of the plane. I pulled out my camera to take a pic, but all of a sudden a lightening bolt discharged right through the nosecone. It jarred the plane so hard that every single passenger felt the huge thud and saw the bright flash. They all were scared pale and asked about it after we landed.

So...which way was the electron flow for that spark? Or was it the "hole" in the nosecone being filled?

LOL

The same way it always does.

St. Elmo's fire and the point of the nose, coupled with conductivity of the plane, provided a path of less resistance than the surrounding air. In essence, you were just in the way. The lesson is St. Elmo's fire while pretty, tells you are in highly electrified air associated with thunder storm activity. Not being an aviator, I do not know how often St. Elmo's Fire precedes a lightening strike, but in your case it did.

Oh, on the battery. I would replace it and have one less thing to worry about. The again, it may work just fine. If you keep it, get a hydrometer so you will be to tell for sure if it is taking a full charge.

CJD
08-27-2012, 10:34 AM
So it could have been in the nose and out the tail, or in the tail and out the nose...making the plane both anode and cathode!

sp53
08-27-2012, 10:45 AM
That is what a condenser does, it absorbs the static electrons. My suggestion is to take some duct tape and a couple of condensers and tape them right below the windshield and that should stop the spark. At least that is what the condenser does in the distributor. Anyone ever see the movie “Mind Walk” it will really get you thinking because all this talk of atoms and electrons might not be true. It is more of a probability than a reality. The periodic table just puts stuff in a nice little mathematical theoretical box. The best kept secret in the Western World is that science is Philosophy!

Geo Hahn
08-27-2012, 11:08 AM
...My suggestion is to take some duct tape and a couple of condensers and tape them right below the windshield and that should stop the spark...

Ooooh -- that's just what I want to see on the front of the plane when I'm boarding: Duct Tape!

CJD
08-27-2012, 11:37 AM
Condenser...Hmmmm....so what we need is a lot of fa, I'm sorry - weight challenged, passengers to absorb the greatest number of electrons!

I knew we could hijack this topic into something useful...

Sorry Afro!?!

Afrodesia
08-27-2012, 01:53 PM
This is great. I had my questioned answered (I assume) &amp; great advice given (will try suggestions first so I can do a lil' learnin' then I'll jus git myself a new battry probly ; )


I already like this place...Lots of IQ floating around. I ask &amp; get a bunch of great responses right away. I wish real life was the same...a girl could get pampered like this!

DanB
08-27-2012, 02:49 PM
Ok, I admit I skipped through a bunch of the really technical discussion, so what I am about to ask may have been covered, but....

Did you take a voltmeter and check the battery? If it is charged backwards it will read negative. Also, with the car running you can check the charging system that way too.


Dan B.

CJD
08-27-2012, 03:14 PM
I just want a ride when your done!

TR6oldtimer
08-27-2012, 08:02 PM
So it could have been in the nose and out the tail, or in the tail and out the nose...making the plane both anode and cathode!

No, just a conductor.

Sorry, I just could not leave it alone.

Hey Aphrodisia, I find a girl with a 59 TR3 attractive. I am single and could pamper you both... :banana:

CJD
08-28-2012, 08:50 AM
No, just a conductor.

Sorry, I just could not leave it alone.



Aaah, it would seem! Except we know that the material from the nosecone was removed, likely deposited back on Mother Earth making the nose the anode. And if soot was deposited - from, say, the nose of another plane - on the tail, we have a cathode.

Given the choice, though, I would preffer to be a conductor, hindered not with gain or loss...

Returning to the original point, though, even with miles of spark ahead, I could still not tell with authority which way the spark passed...

...and I still think the coolest part is that we are driving a car that can be charged backwards and still function. That's just one more cool thing about these cars!

Sarastro
08-29-2012, 03:56 PM
iI've arrived late at this discussion, but a couple of points might clear things up.

First, I hadn't ever thought about this, but it appears that one could indeed charge a battery backwards. When a lead-acid battery is completely discharged, both plates are coated with lead sulphate. When it's charged, one plate is lead, the other lead oxide. The battery works by conversion of the lead and lead oxide to the sulphate.

So, it seems clear that, once it's discharged, you could charge it up either way. Almost certainly, the battery is designed to be charged one way; battery design is a bit more complicated than my simplifications. But I suspect it can be done.

Second, electric current consists of the diffusion of free electrons in a metal. (movement of "holes" applies to semiconductors, but let's not get into that.) Some slight movement of the positive metal ions can happen, but it is not a component of ordinary current. It causes electromigration, which is seen in very small structures with high current densities. The reason for the idea of current moving from positive to negative was developed long before the electron was discovered--I believe that Benjamin Franklin first proposed it. He recognized intuitively that a current involved the movement of some kind of substance, and he hypothesized that the positive pole had an excess and the negative pole a deficit of that substance. I don't know for sure how he got the idea that electricity involved movement of a substance, or figured out which pole had the excess, but I can guess. If you put a pencil point, or other object in a spark, the spark often appears only on one side, and it looks like the motion of a substance in a particular direction.

By time the electron was discovered, all the laws of electricity had been formulated with the idea of positive-to-negative current. As Randall said, it doesn't matter what you use, as long as it is consistent.

DanB
08-30-2012, 03:05 PM
Yes, you can charge a battery backwards. My dad did it on his Ford tractor by accident when I was a kid.

Dan B