n-c alternator modifications: discussion and testing

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DewCatTea-Bob
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Re: 6volt or 12 volt?

Postby DewCatTea-Bob » Sat May 28, 2011 3:07 am

ecurbruce wrote:Bob said; "so that's 6.7 volts P.DC to produce 13.3 wattsDC... it seems that the reduction-effect remains, even with just pulsating DC."

Bob, could you expand any on tbat line of thinking, for clarification? I'm not sure I understand all that' going on there?
Bruce


____ I'll take a stab at that Bruce...
__ It seems that when Bill tested just a single alt.winding alone (while the other was left dead), he measured 13.4-volts AC coming out of the stator-winding. _ Then I converted that that voltage was next reduced to 6.7-volts of Pulsating-DC (by the half-wave rectification). _ However the 13.3 wattage-output (after rectification) was derived merely from the resulting DC-output.
__ I hope that explains that, if not, please ask another question about it.
____ As for my reference to "reduction-effect" still remaining,, not having had a clear understanding of exactly how the stator-windings were coiled/turned & wound, from one core-coil to the next, it was then a notion that when full AC is allowed to flow through both alt.windings (during the commonly used full-wave rectification of both alt.windings connected in series, setup), that possible resulting countering fields of magnetic-flux, may be the explanation for why the two separate alt.windings each-alone produce more power than the two combined-together in 'series' operation.
But now Bill's DC only testing (which shut-down any AC-flow), seems to indicate that the same reduction-effect is still present (even without the counter current-flows of full-AC operation).
So now it seems that even the half-wave rectified P.DC still suffers from the same effect (apparently on it's own & against itself,, either solely all-along or, as well, [depending on whether the effect's ACtoDC ratio has remained consistent or not).
____ How-about telling about both the smaller & the larger coils and their coil-turns, as well as exactly how they were connected to each-other,, and we can then discuss how the suspected canceling-effect is likely working.


Hopeful-Cheers,
-Bob
PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob

DewCatTea-Bob
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Test of Stock Output-power

Postby DewCatTea-Bob » Sat May 28, 2011 6:21 am

wcorey wrote:Since I screwed something up setting that one up, a drawing with all meters would be nice.
Preferred load resistance?
____ Just 1-ohm seems to be most revealing.
The AC-volt-meter reading is not so important, but in this unique circuit test-case, the best use (of the single vac.meter), is across/between either one of the two AC-input terminals of the rect.block & the normally-grounded connection of the two winding lead-ends.
__ I've added the related scheme-drawing, at the top-position of the 3 pic.posts, below.


wcorey wrote:(I was wondering about the unused rec. ground so I jumpered it to the alt. side of the load and got 2.2a, 3.4vac, 2.3vdc, no clue if this means anything at all...)
DewCatTea-Bob wrote:____ I understand that you made a jump-connection from the rect.block's (unused) negative-output to one of the alt.winding leads, (but I don't know which for sure).
" The key to my wording here is "to the alt. side of the load" (as opposed to the rec. side). To be more clear I can see that I should have stated it as 3 and 4 or purple and grey.
Since 3 and 4 are tied together at the load, they were both jumped to ground "

____ Okay, I think I now have a better idea of what you had meant by "ground".
__ Your added jumper-connection may seem like a logical connection to make because bike.mechanic-types naturally relate NEGative to Ground, and since the two alt.windings' lead-ends were 'grounded' (as stock), and the test-rect.block had an unused NEG.output, there's then a naturally-understandable connection that would seem to be needed, between those two points.
However, all that jumped-connection accomplished, is just short-out merely the negative half-cycles (of the full AC-cycles), directly back to each of the two alt.windings.
__ What turns-out to be of special-interest of this unexpected test is that after adding the jumper (and thus shorting-out the sides of the alt.windings which were-not being used to provide our positive-DC power-output, anyhow), the pos.power which was being used to power the load, fell ! _ And it fell by way-more than half, down to just 5-watts !
Now I wouldn't have expected that what happens to the negative-power, would have any effect on the pos.power-output, since the Neg & Pos.circuits are completely separate !
So thus it seems that when the alt.windings are passing max.current during their otherwise unused half-cycles, the opposite half-cycles suffer as well. _ And I see no reason for that, except to help support the counter electro-magnetic / opposed flux-field / power-reduction theory.


wcorey wrote:
DewCatTea-Bob wrote:...the series-connected alt.windings' combined AC-output.... So the test ought to be run again, to clear-up which outcome is most correct.
" No load or rectifier? If loaded, what resistance? Drawings always help, "

____ Yes, same load & rect.block setup, and I now have the related scheme-diagram posted (way-down at bottom, underneath the other two posted-pix).
__ All these latest tests ought be done with the 1-ohm load, since that then allows for direct-comparisons & also indicates the alt.power-output near it's strongest.



" I'll be hanging around with Ken-the-Physicist all day tomorrow, I believe I do have some pertinent questions starting to to organize themselves into a coherent form. The chicken or egg thing with 'voltage' or 'potential voltage ' is a good one if I can figure out how to present it properly (and comprehend the answer). "

____ Hopefully he won't try to dumb-it-down for you (and thus loose some detail).


" I'll try on that one but it requires an explanation that I'm not entirely sure I have a handle on. "

____ Just ask, by what means is it possible that the total-output (of two separate windings on the same core), is less than the total of the (two) individual outputs.


Hopeful-Cheers,
-Bob
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PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob

machten
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Re: 6volt or 12 volt?

Postby machten » Sat May 28, 2011 7:41 am

wcorey wrote:
machten wrote:
...I'm meeting a friend of mine to tutor one of my daughters for her Physics exams. He actually is a Physics professor. Any questions???

Oh yes, have him read the whole thread and offer an opinion...:lol.:
I have a friend that is quite a preeminent Physicist who does a lot of work with high voltage but I wouldn't even have a clue as to what to ask him about this thread.



Me either, Bill! And the loquatious fellow that he is, I'll be all day and as I haven't used my 1st year Uni physics for 30 years, would be none the wiser afterwards anyway. :D

However...

Yes, how about: "Does the varying 'potential' of a running alternator produce any specific voltage value without any external circuitry connected to it ? "
____ Since 'voltage' is merely POTENTIAL-voltage (until OTHER factors form it's value), 'voltage' alone, is an undefined figment.


Seemed simple enough that even I could ask him that. He was of the view that:

Volts are a/the measure of potential (realised or unrealised) and a specific voltage value would exist and its various values produced per load at any point in time could be modelled and calculated by reference to the characteristics of the alternator (magnetic flux, rotational velocity etc) without actually connecting a circuit to it. Connecting a circuit to it merely allows the potential to be realised. The act of connecting the ciruit does not "create" volts or "convert" them from one type to another - they were already there as potential.

EDIT - (and now I'm talking, not the Prof) so if DCT Bob's point is that a specific voltage doesn't exist if you don't know the load, then that seems to me to be right (although so general as to not be useful). If you could specify the load, then I'd disagree. Either way, it seems to me more philosphy or semantics than science. "If a tree falls in the forest and no one is there to hear it, does it make a sound?"

Dunno if that helps or just fuels the fires, but don't shoot me, I'm only a messenger. I'll wait for the "Alternators for Dummies" summary.

Kev

DewCatTea-Bob
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Re: 6volt or 12 volt?

Postby DewCatTea-Bob » Sat May 28, 2011 1:47 pm

" Seemed simple enough that even I could ask him that. He was of the view that:

Volts are a/the measure of potential (realised or unrealised) and a specific voltage value would exist and its various values produced per load at any point in time could be modelled and calculated by reference to the characteristics of the alternator (magnetic flux, rotational velocity etc) without actually connecting a circuit to it. Connecting a circuit to it merely allows the potential to be realised. The act of connecting the ciruit does not "create" volts or "convert" them from one type to another - they were already there as potential. "

____ As I read-through all that, I certainly can agree that the writer knows the field at least well enough to know exactly what he's talking about.
I think Mike would likely agree with that wording overall as well, and I myself find it vague enough that I don't find anything to out-rightly disagree with. _ I think it somewhat skirts the specific question to a degree, (which ought to have gotten a general "No." type response), however all that wording seems completely in-line with my-own view-point quite well enough !
__ Anybody who thinks that I've bent my view-point to become in-line with that wording, has not read & understood that wording as it's actually written.
So as to make this last point clear, I'm itching to point-out where it may seem to disagree with me but actually doesn't. _ But I'll refrain from doing so (for now).

____ Thanks for your effort Kev !


Content-Cheers,
-Bob
PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob

MotoMike
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Re: 6volt or 12 volt?

Postby MotoMike » Sat May 28, 2011 2:05 pm

I can live with it. Bob you have PM

wcorey
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Re: 6volt or 12 volt?

Postby wcorey » Sun May 29, 2011 7:28 am

I'm hesitant get in the middle of what I barely have an understanding of but here goes.
Unfortunately my conversation with Ken-the-Physicist went on for almost an hour and much of it was lost on me at the time and still more since. The topic kept branching off to different related things and got very intertwined. I've been up for 21 hours and am a bit foggy but if I wait until tomorrow I'll likely forget half of it. And I won't be drawn into defending any of this...

has not read & understood that wording as it's actually written.


...is the big problem as it probably applies to me here and obviously affects the phrasing of the questions...

For what it's worth...
He started with something about Maxwell's equations but I think realized it wasn't altogether registering, so I'm sure he 'dumbed it down' from there...

The 'voltage potential' thing was most the clear to me but still difficult to for me to put into words without confusing things even more. For one thing, the usage of the word 'potential' in the context of this subject is potentially confusing in that it can have multiple meanings. You could say a circuit has 'the potential for 'x' voltage', meaning that if it was not yet energized, it would have 'x' voltage when switched on, doesn't seem to really apply here though and wouldn't normally be used in any real technical sense .
When you say 'potential voltage', it's basically redundant as 'potential' and 'voltage are virtually analogous/interchangeable terms (when used to describe electricity), it's like saying 'voltage voltage'.
He said that voltage can indeed be measured without having any flow of current, either theoretically or with an extremely high impedance meter.
One analogy he used to describe voltage was gravity, which evidently uses pretty much the same mathematical equations. Nothing has to be moving for gravity to be exerting force (potential), just because the force is 'sitting there' doesn't mean it's not there at all in that moment in time. So voltage can exist whether electrons are flowing or not.
My own conclusion is that in the context of our topic, 'voltage' and 'potential voltage' are the same thing, assuming the circuit is energized.

Something else I inquired about was the question of whether AC voltage exists in the alternator when it's being rectified to DC in the circuit. The simple answer from a complicated explanation was yes.

He was interested in the alternator problem but again very quickly got over my head with explanations of the possible interactions of eddy currents, etc., etc. and didn't come to a conclusion as we were interrupted by other social obligations. Said he would give it some more thought later...

There's much more but I'm fading, need to sleep, will continue later...


Bill

DewCatTea-Bob
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Voltage vs. mere Potential, (is as, Volume vs. mere Space)

Postby DewCatTea-Bob » Sun May 29, 2011 1:27 pm

____ Okay, it's pretty clear that Bill's friend has the same understanding as Mike about what 'voltage' is... they both see no difference between 'voltage' & 'potential' .
'That seems to make me wrong and I wouldn't disagree that I'm not right in THEIR field.
However, between all those who are not so trained in the field, why should two different words with clearly different meanings still mean the very same thing ??
I (for one) say that those two words exist because they DO have different meanings (even if there are those who chose to recklessly use them interchangeably) ! _ To use them interchangeably is clearly wrong, cuz otherwise, how could someone make himself understood about exactly what he's talking about, without having to go-through all this BS that I've been having to go through, concerning this (particular aspect of terminology) matter ?
__ I'm sure anyone else (how hasn't been trained to think of both words as the very same), would not disagree that the term: 'potential' covers voltage which has no specific value,, while the name: 'voltage' is more-so measurement-specific to a measured or calculated amount of potential, or quantity of volts. _ (Just as 'volume' & 'space' cover the same thing but, 'volume' is ALSO specific to a 'measurement' of it !)
How could that clear separation (of the two words) not be reasonably obvious to the common-man ?
Why else would the specific word 'potential' be adapted to also refer to 'voltage' ? _ It's not as if the English-language has no logic behind it ! _ Obviously there's been a need to be able to refer to voltage without quantifying it. _ It seems obvious that the related tech.field has simply lost track over the decades, the reasoning for the term 'potential'.
(And at the rate I see things going these days, someday someone like me will be trying to tell others who think otherwise, that 'for' & '4' [or 'u' & 'you'] are not the same thing.)
__ It would seem that if the related tech.field-types ever takeover the common-man's battery-factories, we'll then likely see labeled on the sides of their D-cells '1.5
Potential', (I dread the day !).


Discontent-Cheers,
-Bob


Note below that MotoMike has given examples of terms which can each have a specific use, OR, may mean exactly the same thing,, all depending on how much the specific definitions are 'dumbed-down' (for ease of understanding, [for easier teaching to a wide range of mentalities],, and just as when children grow up, we all begin to [sooner or later] come to realize the various distinctions).
PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob

MotoMike
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Re: 6volt or 12 volt?

Postby MotoMike » Sun May 29, 2011 5:52 pm

Hmm words that are different but mean the same thing... that's scary, frightening, terrifying, blood-curdling, chilling, fearsome, nerve-wracking, eerie, sinister, spooky, alarming, petrifying, hair-raising, bone-chilling, horrifying, and unnerving.

It should be noted that it happens with some frequency in the English language, though.

Bevel bob
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Re: 6volt or 12 volt?

Postby Bevel bob » Wed Jun 01, 2011 8:10 am

And I still have not learnt anything usefull!!. Sounds like I'm going to have to fit a ampmeter and try a selection of headlamp bulbs to find out what my system can can stand.Think its called empherical approach.

wcorey
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Re: 6volt or 12 volt?

Postby wcorey » Wed Jun 01, 2011 9:27 pm

Took a break from testing, actually worked on the bike instead. I swear I'd be running it by now if I didn't keep getting sidetracked with these related side projects. As with many things, the testing itself takes hardly any time at all, it's trying to translate test requests that may or may not be in a consistent format and going back to re-read posts and my past data to figure out what I'm doing that takes all the time. I think I'm a bit ADHD and have too many things going at once, leads to confusion and second guessing everything...

" Am I now up to date with the test requests? "

____ I believe you've tried all the various possibilities, however before you tear-down your setup... I believe you've had a test-result that didn't check-out to be exactly confirmed... Once, (as I think I recall), the series-connected alt.windings' combined AC-output was simply somewhat less than double that of either winding alone, while another AC-test indicated that the series combined output of both was actually a bit LESS than either alt.winding's output by itself.
So the test ought to be run again, to clear-up which outcome is most correct.


I'm confused by the above statements in bold, they both sound like the same thing but worded differently. Could you re-phrase so it registers another way in my brain?



wcorey wrote:

DewCatTea-Bob wrote:...the series-connected alt.windings' combined AC-output.... So the test ought to be run again, to clear-up which outcome is most correct.

" No load or rectifier? If loaded, what resistance? Drawings always help, "

____ Yes, same load & rect.block setup, and I now have the related scheme-diagram posted (way-down at bottom, underneath the other two posted-pix).
__ All these latest tests ought be done with the 1-ohm load, since that then allows for direct-comparisons & also indicates the alt.power-output near it's strongest.


Same as what? Is this the same as what's in the previous quote? There are no values on the drawing and too much time has passed for me to recall which particular past test we are comparing to.


And I still have not learnt anything usefull!!.


Patience... Test data is almost complete, then the analysis will hopefully commence in earnest. Between D-Bob, Mike and Bruce + Dad, we should get some results that will get us 55W headlights.
I had thought that Ducati-Bob was all ready to pull a rabbit out of his hat and the light bulb of enlightenment would then light for all of us but the test data has seemingly thrown a wrench into the hat and maybe the answers are not so obvious. I still feel that something practical will emerge from this often divisive and confusing thread... Probably in two or three different and arguable versions, lol.

Sounds like I'm going to have to fit a ampmeter and try a selection of headlamp bulbs to find out what my system can can stand.


I'd be happy to save you some work, I could emulate your setup as close as I can and throw a few light bulbs at it, that's basically how I started out with the whole thing...
I can tell you that a series connected stator (grounds lifted, still connected together) will readily fry a 55w bulb at 6k rpm when left unregulated.


Bill


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