" I understand both of your points of view
____ That you can comprehend both view-points Bruce, suggests that you're capable enough to understand ANY means for reaching the bottom-line, regardless of mind-set method,, and that's the way to be. _ So good for you !
____ I've been trying to get the discussion to reach a goal I've had in mind, and after that revelation has been reached, then branching-over to other things ought make better sense.
So next I wish to take-up where I think we left-off.....
____ At this point it looks like I'm the only one who's really caring to narrow-down the possible story on how Ducati's 6-pole 4 core-coil alt.stator came to be rated at '60-watts' specifically.
Now when we note that Ducati's 6-pole 6 core-coil version is rated at only 70-watts even though it has 50% more core-coils, could simply mean that the 70w-version has less total coil-turns per alt.winding, OR perhaps Ducati had rated it by a different method...
Now I can believe that wide-case 70w-version produces 70-watts 'RMS' -(which basically represents the ratio at which the AC-waveform will match an equal amount of straight-line DC power-juice, [that ratio being 1:1.414 -(the square-root of 2) ]),, however with that being a possible case, that then helps make the case that the 33% less-full n-c version probably doesn't produce 60-watts 'RMS'.
And while I've never come to a firm conclusion, I have accepted that the '60w' 6-pole 4 core-coil n-c alternator probably deserves to earn a rating of 60-watts AC 'peak-to-peak' from EACH of it's two alt.windings, (averaged-out, during expected normal engine-RPMs).
Now that would mean that each winding alone ought produce 42.5 AC watts RMS - (that's actually 60w AC / 1.414 = 42.43w).
So the combined AC power-output of both alt.windings together (in series OR parallel), would then be 85-watts RMS. _ (Rather than 120w, as has been fairly logically suggested.)
__ However since the stock rectifier set-up does not allow any use of the 'negative-halves' of the AC-cycles of either of the two alt.windings, that then of course means that the equivalent DC-wattage would become halved-down to (nearly) 42.5-watts (total output for the stock charging-system),, which incidentally, seems fairly close to that which is actually available from this charging-system that's in question.
____ I still intend to take this discussion through to further (likely unrealized) notions.
Tillater,
DCT-Bob
Can stock alternator produce more volts and power?
Moderator: ajleone
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DewCatTea-Bob
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Re: 6volt or 12 volt?
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
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DewCatTea-Bob
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Re: 6volt or 12 volt?
By: MotoMike...
" As you said before bob, it's not important whose right, it is important to find what is right. "
____ Agreed! _ At least on that we have something we can both agree on here.
__ And should you ever PROVE something which I'm truely wrong about,, I for one, will be thankful & say so.
" Maybe those superior techs who let you go on without trying to correct your misconceptions were either not the super techs you thought "
____ I haven't had any professors check-over any of my writings on this w.site,, however such as their sort, would have no trouble comprehending my conclusions, as they're actually without real fault ! ...
Just because my valid conceptions are not derived exactly the very same way which you've been trained (by convention) to conceive yours, does-NOT mean that mine must be "misconceptions" which therefore have to be wrong ! (However my conceptions could possibly be considered as misconceptions from the convention's narrow-minded point of view.) _ It doesn't really matter one way or the other though, since the end-result is the SAME !
Content-Cheers,
-Bob
" As you said before bob, it's not important whose right, it is important to find what is right. "
____ Agreed! _ At least on that we have something we can both agree on here.
__ And should you ever PROVE something which I'm truely wrong about,, I for one, will be thankful & say so.
" Maybe those superior techs who let you go on without trying to correct your misconceptions were either not the super techs you thought "
____ I haven't had any professors check-over any of my writings on this w.site,, however such as their sort, would have no trouble comprehending my conclusions, as they're actually without real fault ! ...
Just because my valid conceptions are not derived exactly the very same way which you've been trained (by convention) to conceive yours, does-NOT mean that mine must be "misconceptions" which therefore have to be wrong ! (However my conceptions could possibly be considered as misconceptions from the convention's narrow-minded point of view.) _ It doesn't really matter one way or the other though, since the end-result is the SAME !
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
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ecurbruce
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Re: 6volt or 12 volt?
Bob said- "Now when we note that Ducati's 6-pole 6 core-coil version is rated at only 70-watts even though it has 50% more core-coils, could simply mean that the 70w-version has less windings, OR perhaps Ducati rated it by a different method... "
Could it be that the magnets would have to be increased by the same 50% for a full 50% gain in watts?
Could it be that the magnets would have to be increased by the same 50% for a full 50% gain in watts?
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DewCatTea-Bob
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Re: 6volt or 12 volt?
" Could it be that the magnets would have to be increased by the same 50% for a full 50% gain in watts? "
____ The 50% difference I was referring to is that while both the w-c & the n-c alternators have 6-poles each, the n-c version only has 4 core-coils. - That's two larger & two smaller core-coils (two-pairs), whereas the w-c has three such pairs of core-coils, thus the extra pair makes a 50% increase.
Your question would certainly be valid if the 4 core-coil alt.version also had just 4-magnets, but both (n-c & w-c) alt.rotors already have 6-magnets.
(But if the magnets alone were to be somehow increased 50%, then that change alone itself would provide a 50% increase, as well.)
__ So incidently, if I'm correct that the stock n-c 6-pole alternator is good for 85-watts RMS, then your neatly modified version ought be good for about 127-watts RMS (or 180-watts peak-to-peak).
Dukaddy-DUKEs,
-Bob
____ The 50% difference I was referring to is that while both the w-c & the n-c alternators have 6-poles each, the n-c version only has 4 core-coils. - That's two larger & two smaller core-coils (two-pairs), whereas the w-c has three such pairs of core-coils, thus the extra pair makes a 50% increase.
Your question would certainly be valid if the 4 core-coil alt.version also had just 4-magnets, but both (n-c & w-c) alt.rotors already have 6-magnets.
(But if the magnets alone were to be somehow increased 50%, then that change alone itself would provide a 50% increase, as well.)
__ So incidently, if I'm correct that the stock n-c 6-pole alternator is good for 85-watts RMS, then your neatly modified version ought be good for about 127-watts RMS (or 180-watts peak-to-peak).
Dukaddy-DUKEs,
-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
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MotoMike
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Re: 6volt or 12 volt?
Bob wrote: And while I've never come to a firm conclusion, I've accepted that the '60w' 6-pole 4 core-coil n-c alternator probably deserves to earn a rating of 60-watts AC peak-to-peak from EACH of it's two alt.windings.
Now that would mean that each winding alone ought produce 42.5 AC watts RMS - (that's actually 60w AC / 1.414 = 42.43w).
So the combined AC power-output of both alt.windings together, would then be 85-watts RMS. _ (Rather than 120w, as has been suggested.)
I don't know how the 60 watt rating came to be. Until we see the engineering notes we won't. I suppose it is possible the method described was used. seems odd to me, but anything is possible. Since we don't know, it's as valid as other theories.
One thing that I note is that formula for converting peak-peak to rms is missng a step. I think it should be peak divided by 1.414 not peak to peak. so in the given example it should be pp/2/1.414. this is the formula I mentioned before stated differently. I think it is about the simplest way to express the formula for rms. RMS=pp/2 x.707
should be:
60/2=30 /1.414 =21.21. using the correct formula won't get you to the numbers you have.
the numbers would work if the initial value was 120 peak to peak instead of 60.
Bob I read you mention testing that suggested what the real numbers are. but did not include the link or state the testing and results. I could not find that info, what was the testing and what are the figures? that could solve the issue.
Assuming the tested alternator was representative of the majority. I only mention this because magnet strength plays a huge part in the perfomance of the alternator. don't recall the formula, but a magnet twice as strong won't yeild an output twice as much. distance from magnet to core also has a similar effect, again not recalling the formula, but twice as far away from the coils will yield a far bigger loss of output than half as much.
Now that would mean that each winding alone ought produce 42.5 AC watts RMS - (that's actually 60w AC / 1.414 = 42.43w).
So the combined AC power-output of both alt.windings together, would then be 85-watts RMS. _ (Rather than 120w, as has been suggested.)
I don't know how the 60 watt rating came to be. Until we see the engineering notes we won't. I suppose it is possible the method described was used. seems odd to me, but anything is possible. Since we don't know, it's as valid as other theories.
One thing that I note is that formula for converting peak-peak to rms is missng a step. I think it should be peak divided by 1.414 not peak to peak. so in the given example it should be pp/2/1.414. this is the formula I mentioned before stated differently. I think it is about the simplest way to express the formula for rms. RMS=pp/2 x.707
should be:
60/2=30 /1.414 =21.21. using the correct formula won't get you to the numbers you have.
the numbers would work if the initial value was 120 peak to peak instead of 60.
Bob I read you mention testing that suggested what the real numbers are. but did not include the link or state the testing and results. I could not find that info, what was the testing and what are the figures? that could solve the issue.
Assuming the tested alternator was representative of the majority. I only mention this because magnet strength plays a huge part in the perfomance of the alternator. don't recall the formula, but a magnet twice as strong won't yeild an output twice as much. distance from magnet to core also has a similar effect, again not recalling the formula, but twice as far away from the coils will yield a far bigger loss of output than half as much.
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DewCatTea-Bob
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Re: 6volt or 12 volt?
" One thing that I note is that formula for converting peak-peak to rms is missng a step. I think it should be peak divided by 1.414 not peak to peak. so in the given example it should be pp/2/1.414. "
____ That 'divide-by-2' additional step, is for conversion of half-cycle (pulsating)- DC, (as opposed to full-cycle AC).
The figures I've given are valid for the 'FULL' AC-waveform, as the 'RMS' conversion-factor is equally valid for AC as well ! _ Further in other words, the RMS correction-factor/conversion-factor is applicable to either, the full AC-waveform, OR, the remaining half-cycle, after rectification !
" this is the formula I mentioned before stated differently. I think it is about the simplest way to express the formula for rms. RMS=pp/2 x.707 "
____ That stated formula is only in reference to just 'one-half' of the complete AC sine-wave, (and either HALF of the AC-cycle is pulsating 'DC') !
" should be:
60/2=30 /1.414 =21.21. using the correct formula won't get you to the numbers you have. "
____ You-yourself haven't made it clear exactly what "correct formula" YOU're in reference to.
I-myself was only in reference to the alternator's 'AC' output ! _ Thus MY figures are still left as (complete) 'AC' , (since the alternator itself ought not be rated in 'half-cycle' DC-watts) !
If you (properly) add the two DC-halves (of the AC-cycle) together, THEN YOUR figures match mine !
" Bob I read you mention testing that suggested what the real numbers are. "
____ Well not that exactly-so Mike... fellow-member 'wcorey' did some testing on the 4 core-coil n-c alternator, but only at a mid-range RPM.
If when you joined-up here, you had not seen his/Bill's related postings, then they must've been posted not long before the date when you registered.
" but did not include the link or state the testing and results. I could not find that info, what was the testing and what are the figures? that could solve the issue. "
____ I'll see if I can find his first related post soon.
__ He did not test the entire n-c charging-system as stock, but rather tested only it's series-jumped alt.stator with FW-bridge rectification (unfortunately including a regulator with unknown characteristic-effects, [I believe]).
It should thus be kept in mind that his results are only reflective of an alternator's entire 'AC' peck-to-peak power-output (for rating purposes).
However I agree that his testing should put us in the ball-park.
Now Updated (with added/edited wording)!
-Bob
____ That 'divide-by-2' additional step, is for conversion of half-cycle (pulsating)- DC, (as opposed to full-cycle AC).
The figures I've given are valid for the 'FULL' AC-waveform, as the 'RMS' conversion-factor is equally valid for AC as well ! _ Further in other words, the RMS correction-factor/conversion-factor is applicable to either, the full AC-waveform, OR, the remaining half-cycle, after rectification !
" this is the formula I mentioned before stated differently. I think it is about the simplest way to express the formula for rms. RMS=pp/2 x.707 "
____ That stated formula is only in reference to just 'one-half' of the complete AC sine-wave, (and either HALF of the AC-cycle is pulsating 'DC') !
" should be:
60/2=30 /1.414 =21.21. using the correct formula won't get you to the numbers you have. "
____ You-yourself haven't made it clear exactly what "correct formula" YOU're in reference to.
I-myself was only in reference to the alternator's 'AC' output ! _ Thus MY figures are still left as (complete) 'AC' , (since the alternator itself ought not be rated in 'half-cycle' DC-watts) !
If you (properly) add the two DC-halves (of the AC-cycle) together, THEN YOUR figures match mine !
" Bob I read you mention testing that suggested what the real numbers are. "
____ Well not that exactly-so Mike... fellow-member 'wcorey' did some testing on the 4 core-coil n-c alternator, but only at a mid-range RPM.
If when you joined-up here, you had not seen his/Bill's related postings, then they must've been posted not long before the date when you registered.
" but did not include the link or state the testing and results. I could not find that info, what was the testing and what are the figures? that could solve the issue. "
____ I'll see if I can find his first related post soon.
__ He did not test the entire n-c charging-system as stock, but rather tested only it's series-jumped alt.stator with FW-bridge rectification (unfortunately including a regulator with unknown characteristic-effects, [I believe]).
It should thus be kept in mind that his results are only reflective of an alternator's entire 'AC' peck-to-peak power-output (for rating purposes).
However I agree that his testing should put us in the ball-park.
Now Updated (with added/edited wording)!
-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
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MotoMike
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Re: 6volt or 12 volt?
Bob wrote:
That added divide by 2 step, is for conversion to half-wave DC,, however the figures I've given are valid for the FULL AC-waveform, as the 'RMS' conversion-factor is equally valid for AC as well.
MMI don't know what you are saying here. it doesn't make sense to me. formula for peak to peak to rms doesn't have specific sub sets for how it is used.
Bob wrote:
____ That's only in reference to just 'one-half' of the complete AC sine-wave, (and either half of the AC-cycle is 'DC') !
MM
Nope, that is the simplified formula for RMS from a Peak to Peak sine wave signal. (p-p/2 x .707) (I think it works for saw tooth, but is different for square wave) it goes to show you just how much less power is available in the sine wave. Early in my tech life I made this same mistake for a while till someone saw what I was doing and corrected me. A 200 volt peak to peak wave form will produce the same heat in a given resistor as 70.7 volt dc source. You do know that the vast majority of ac volt meters read in rms? If they read otherwise they will have plenty of labling that will make it clear.
That added divide by 2 step, is for conversion to half-wave DC,, however the figures I've given are valid for the FULL AC-waveform, as the 'RMS' conversion-factor is equally valid for AC as well.
MMI don't know what you are saying here. it doesn't make sense to me. formula for peak to peak to rms doesn't have specific sub sets for how it is used.
Bob wrote:
____ That's only in reference to just 'one-half' of the complete AC sine-wave, (and either half of the AC-cycle is 'DC') !
MM
Nope, that is the simplified formula for RMS from a Peak to Peak sine wave signal. (p-p/2 x .707) (I think it works for saw tooth, but is different for square wave) it goes to show you just how much less power is available in the sine wave. Early in my tech life I made this same mistake for a while till someone saw what I was doing and corrected me. A 200 volt peak to peak wave form will produce the same heat in a given resistor as 70.7 volt dc source. You do know that the vast majority of ac volt meters read in rms? If they read otherwise they will have plenty of labling that will make it clear.
Last edited by MotoMike on Wed May 18, 2011 6:01 pm, edited 1 time in total.
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MotoMike
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Re: 6volt or 12 volt?
from bobs post:
should be:
60/2=30 /1.414 =21.21. using the correct formula won't get you to the numbers you have. "
____ You-yourself haven't made it clear exactly what "correct formula" YOU're in reference to.
I-myself was only in reference to the alternator's 'AC' output ! _ Thus MY figures are still left as (complete) 'AC' , (since the alternator itself ought not be rated in 'half-cycle' DC-watts) !
If you (properly) add the two DC-halves together, THEN YOUR figures match mine !
MM
Sorry, thought I had.
you said "60-watts AC peak-to-peak from EACH of it's two alt.windings" it is the correct formula for that statement. if each winding was 60 peak to peak, each winding output would be 21.21 rms. added together (which I don't think is correct) would be 42.42. rms total.
should be:
60/2=30 /1.414 =21.21. using the correct formula won't get you to the numbers you have. "
____ You-yourself haven't made it clear exactly what "correct formula" YOU're in reference to.
I-myself was only in reference to the alternator's 'AC' output ! _ Thus MY figures are still left as (complete) 'AC' , (since the alternator itself ought not be rated in 'half-cycle' DC-watts) !
If you (properly) add the two DC-halves together, THEN YOUR figures match mine !
MM
Sorry, thought I had.
you said "60-watts AC peak-to-peak from EACH of it's two alt.windings" it is the correct formula for that statement. if each winding was 60 peak to peak, each winding output would be 21.21 rms. added together (which I don't think is correct) would be 42.42. rms total.
Last edited by MotoMike on Wed May 18, 2011 6:12 pm, edited 1 time in total.
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MotoMike
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Re: 6volt or 12 volt?
Bob wrote:
____ Well not that exactly-so Mike... fellow-member 'wcorey' did some testing on the 4 core-coil n-c alternator, but only at a mid-range RPM.
If when you joined-up here, you had not seen his/Bill's related postings, then they must've been posted not long before the date when you registered.
MM
I think I found that but didn't read where he stated the output of the alternator. Maybe I didn't find the right post.
____ Well not that exactly-so Mike... fellow-member 'wcorey' did some testing on the 4 core-coil n-c alternator, but only at a mid-range RPM.
If when you joined-up here, you had not seen his/Bill's related postings, then they must've been posted not long before the date when you registered.
MM
I think I found that but didn't read where he stated the output of the alternator. Maybe I didn't find the right post.
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DewCatTea-Bob
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Re: 6volt or 12 volt?
MotoMike wrote:Bob wrote:
That added divide by 2 step, is for conversion to half-wave DC,, however the figures I've given are valid for the FULL AC-waveform, as the 'RMS' conversion-factor is equally valid for AC as well.
MMI don't know what you are saying here. it doesn't make sense to me. formula for peak to peak to rms doesn't have specific sub sets for how it is used.
____ Sorry, I did not mean for my (poorly stated) wording to be taken as you have. _ I will go fix it (& leave note when I have).
Bob wrote:
____ That's only in reference to just 'one-half' of the complete AC sine-wave, (and either half of the AC-cycle is 'DC') !
"MM
Nope, that is the simplified formula for RMS from a Peak to Peak sine wave signal. (p-p/2 x .707) "
____ I'm lost to exactly what you mean by "that" , so I can't realize what you're saying "Nope" in regards to.
" (I think it works for saw tooth, but is different for square wave) "
____ The correction-factor (for conversion to straight-line DC), which is based on the sq.rt of 2, is only for 'SINE-wave' waveforms. _ (Others such as square-wave have other correction factors).
" Early in my tech life I made this same mistake "
____ Exactly what "mistake" are you referring to ?
" A 200 volt peak to peak wave form will produce the same heat in a given resistor as 70.7 volt dc source. "
____ Yes, I agree with those figures because after dividing by "2", ya then have the power effect of just one-HALF of the sine-wave, (just as a [single]- diode converts AC to DC), passing-through your "given resistor" example.
(Otherwise you'd have us thinking that 120vAC ('house-current') is only equivalent to just 60vDC. _ Right ? )
Once again, let's keep in mind that when we're considering alternator-output, we must consider the ENTIRE waveform, (thus BOTH halves of the AC-cycle, not just a rectified portion of it.)
" You do know that the vast majority of ac volt meters read in rms? "
____ Yes, of course... And when it's AC read-out is converted to the equivalent amount in DC, it's NOT only half the indicated AC value.
Fun-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
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