Can stock alternator produce more volts and power?

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MotoMike
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Can stock alternator produce more volts and power?

Postby MotoMike » Wed May 11, 2011 7:21 pm

Not sure if this is the best place for this or not. if not feel free to move it.

Image


If we look at the schematic of the system, we can see that the rectifier circuit is fused at 10 amps. As we have previously discussed elsewhere, each half of the stator coils on either side of the center tap or ground connection can have different instantaneous loads during their half cycle of the input wave, which is induced by the rotating magnetic field of the permanent magnet rotor. Mentioned already are 25 and 10 watts as examples. Since the circuit is fused at 10 amps and loads are 6volt, the circuit is designed to provide up to 60 watts. Since this is a system that I have read is robust, I believe that the original designers used good engineering principals. In so doing they did not fuse it at it's absolute maximum, but built in a safety margin so that the fuse went well before the coils or other components were self-destructing.

I take from this that each coil must be able to handle the full current before the waveform transitions to the other half cycle and the other coil takes over. So then, if the two halves of the alternator stator are altered to be in series with one another. The ground connection at their center is lifted from ground and insulated so that the coils remain connected but it can’t contact anything, you would have twice the voltage output and the same current carrying capability. This will result in twice the available wattage from the alternator. Since this modification routinely involves installing a modern 12-volt regulator with a bridge rectifier in it, you would see 12 volts at a max of 10 amps or 120 watts available from the system.

It is probably important to consider that an advantage in the original design is that each half of the stator coils conduct for only 180 degrees of the 360 input, consequently they get a rest between conducting half cycles. When configured in series they will have current through them all the time. (Except for the instant when the waveform is passing zero). This is something to consider as changing the duty cycle from 50% to 100% at a given current flow will certainly be harder on it than the original design. What the de-rating should be, I don’t know as some margin of safety was surely designed into the original system. I would not try to get 120 watts out of it though.

It should also be noted that if you changed the system over to 12 volts and kept all the wattage requirements the same, the current needed through the system to provide for the same wattage would be half. As an example, a 6 volt 35 watt bulb would draw about 5.83 amps where a 12 volt 35 watt bulb would be drawing only about 2.91 amps. Of course one of the reasons to consider the change would be to run more or more easily available loads such as a modern electronic tach, brighter lights and/or an electronic ignition.

Elsewhere it has been stated that if the 10-amp 6 volt 60 watt alternator is converted to 12 volts it will still only produce 60 watts but now at 5 amps.

I think this idea comes from the coils being in parallel with one another. The general rule is that current in parallel is additive, so the thought here is that if the max is 10, then they must each handle 5. This rule would apply if they were conducting at the same time, but they are switched by the biasing of the diodes so that their current is never added together, it is always one coil and diode conducting while the other is not, then switching with the changing of polarity. So they are taking turns and each provides all the current to the system during it’s turn.


Also elsewhere it has been stated that the wattage rating is optimistic. Ducati wouldn’t be the first to do that if it is so. That perhaps only at high rpms, that is to say rpm’s used only in racing, can it produce the rated output. I don’t know what the truth is here, as I don’t have a lot of experience with these systems. But if you figure 35 watts for the headlight, 10 for the ignition and 10 for running/brake and the system can keep your battery well charged under normal use, then it must be providing around 60 watts.

Speaking only about the system pictured here, I believe that whatever wattage it can produce at 6 volts, it can produce twice that when reconfigured as described above at 12 volts. I would probably de-rate it owed to the 100% duty cycle though.

DewCatTea-Bob
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Re: Can stock alternator produce more volts and power?

Postby DewCatTea-Bob » Sat May 14, 2011 5:50 am

By: MotoMike...
" each half of the stator coils on either side of the center tap or ground connection can have different instantaneous loads during their half cycle of the input wave, "

____ I'd certainly agree with such possibility in OTHER such circuits of the sort but, I believe it needs to be kept in mind in THIS case that it's the BATTERY which will have to handle any such abruptly sudden change in load circumstance (such as horn or brake-light), thus a (relatively super-short) "half cycle" won't reflect any significantly notable change in the load-burden (from one cycle to the very next).
__ As I've tried to make point of before, electrical power-source systems have quite different characteristics depending on whether or not they include a storage-battery, therefore such related circuits should always be discussed as if intended either with, or without, a storage-battery, (and not ALWAYS as if there's no battery included).
__ If I seem to have missed some other point which was actually the specific-point (concerning "instantaneous loads"), then I must need further clarification of whatever the intended point was meant to be.


" Mentioned already are 25 and 10 watts as examples. "

____ Something which it seems I failed to make clear when I gave my example of a center-tapped power-source providing both 25w & 10w half-waves (to complete a "full-wave"), is that I wasn't actually referring to the Ducati-system, but rather a similar center-tapped like circuit with a 'center-tapped transformer' which has it's chosen (so-called)- "center tap" not actually 'centered' -(right in between the opposite-ends).
And that example was merely meant for helping to make my case that the combined-output, (while 'technically' a "full wave" wave-form), would not be "FULL" (as would be the case if either the 25w OR the 10w side -[of the center-tap] had been 'FULLwave-rectified' -[as with a FW-bridge] ).


" but built in a safety margin so that the fuse went well before the coils or other components were self-destructing. "

____ The fuse was probably mostly intended for protecting the power-diodes from overheating, rather than the alt.coils,, cuz I've come-across cases where alt.coils were left short-circuited (externally at the alt.wire-leads) for extended time-periods,
and even though toasted-brown, still remained in working-condition.


" I take from this that each coil must be able to handle the full current before the waveform transitions to the other half cycle and the other coil takes over. "

____ I-myself find that this wording should be clarified, as to exactly what's meant to be referred to by: "this", and by: "the full current" .


" It is probably important to consider that an advantage in the original design is that each half of the stator coils conduct for only 180 degrees of the 360 input, consequently they get a rest between conducting half cycles. "

____ I'm finally relieved that you've now used wording which outwardly agrees with that which I've been proclaiming all-along, (and not seemingly in opposition, as of recently) !


" Elsewhere it has been stated that if the 10-amp 6 volt 60 watt alternator is converted to 12 volts it will still only produce 60 watts but now at 5 amps.
I think this idea comes from the coils being in parallel with one another. "

____ I think it was Jim (for one) who may've declared that logical conclusion.
However in such case, the alt.stator need not be converted... as only the battery & system-loads would then need to be converted to equivalent 12-volt items, (along with the black-box's wire-wound resistor & possibly 'C1').


" The general rule is that current in parallel is additive, so the thought here is that if the max is 10, then they must each handle 5. This rule would apply if they were conducting at the same time, but they are switched by the biasing of the diodes so that their current is never added together, it is always one coil and diode conducting while the other is not, then switching with the changing of polarity. So they are taking turns and each provides all the current to the system during it’s turn. "

____ All that wording really can't be faulted (or confirmed) since it seems that you may have purposely stopped-short of stating the related figures, so that checking of your logic couldn't be done !?
So I think it needs to be asked/confirmed whether you mean to indicate that two (for example)- 5-amp half-wave pulses both occurring at once, is 10-amps total,, while two (for example)- 10-amp half-wave pulses occurring alternately, is still only 10-amps total,,
or just exactly whatever you actually mean specifically.
And to help others follow-along, please relegate your examples to JUST the stock SIX-volt n-c system only, (as your posted diagram pertains to).
I'm asking for such clarification in hopes that it will be presented with wording that's correlated with your wording above, however with all related figures included along-with.


" Also elsewhere it has been stated that the wattage rating is optimistic. "

____ If it was myself who ever used wording which indicated that as likely, then I would've meant to state-so only in relation to it's 'average-output' (during normal intended use of the engine while near regular speeds).
I think the '60-watt' rating is a probably a maximum acceptable amount that could be achieved without exceeding acceptable reliability.
I also think that Ducati had figured-in that their 6-pole alternator's 2 pairs of core-coils were about on-par with their 4-pole alternator's twin core-coils, and so the extra 50% of power (60 vs 40w) was achieved mainly due to the 50% increase in frequency (due to the 2 additional poles).


" But if you figure 35 watts for the headlight, 10 for the ignition and 10 for running/brake and the system can keep your battery well charged under normal use, then it must be providing around 60 watts. "

____ I'm sure that's not a fair assessment...
Only constant loads such as ignition & running-lights, and even the battery & regulator consume power-juice at a rather steady rate, and that's all the alternator's power has to balance against,, while the horn & brake-light merely use the same current-juice which the battery had already taken-in.


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

MotoMike
Posts: 487
Joined: Wed Aug 04, 2010 3:40 am

Re: Can stock alternator produce more volts and power?

Postby MotoMike » Sat May 14, 2011 5:58 pm

DewCatTea-Bob wrote:By: MotoMike...
" each half of the stator coils on either side of the center tap or ground connection can have different instantaneous loads during their half cycle of the input wave, "

____ I'd certainly agree with such possibility in OTHER such circuits of the sort but, I believe it needs to be kept in mind in THIS case that it's the BATTERY which will have to handle any such abruptly sudden change in load circumstance (such as horn or brake-light), thus a (relatively super-short) "half cycle" won't reflect any significantly notable change in the load-burden (from one cycle to the very next).
__ As I've tried to make point of before, electrical power-source systems have quite different characteristics depending on whether or not they include a storage-battery, therefore such related circuits should always be discussed as if intended either with, or without, a storage-battery, (and not ALWAYS as if there's no battery included).
__ If I seem to have missed some other point which was actually the specific-point (concerning "instantaneous loads"), then I must need further clarification of whatever the intended point was meant to be.

MM
showing that each is acting separately.


" Mentioned already are 25 and 10 watts as examples. "

____ Something which it seems I failed to make clear when I gave my example of a center-tapped power-source providing both 25w & 10w half-waves (to complete a "full-wave"), is that I wasn't actually referring to the Ducati-system, but rather a similar center-tapped like circuit with a 'center-tapped transformer' which has it's chosen (so-called)- "center tap" not actually 'centered' -(right in between the opposite-ends).
And that example was merely meant for helping to make my case that the combined-output, (while 'technically' a "full wave" wave-form), would not be "FULL" (as would be the case if either the 25w OR the 10w side -[of the center-tap] had been 'FULLwave-rectified' -[as with a FW-bridge] ).

MM
I thought your examples pertained to the present real world situation. at any rate weather you meant to or not, you are correct as it pertains to the real world. but only technically as each stator coil must experience different loads as one must experience if first. they may be the same on the next cycle, but since they don't conduct at the same time, one must be first, so they do see different loads. If truly in parallel, they would see the same loads at the same time.


" but built in a safety margin so that the fuse went well before the coils or other components were self-destructing. "

____ The fuse was probably mostly intended for protecting the power-diodes from overheating, rather than the alt.coils,, cuz I've come-across cases where alt.coils were left short-circuited (externally at the alt.wire-leads) for extended time-periods,
and even though toasted-brown, still remained in working-condition.

MM
I guess you are agreeing that they are robust and can handle 10 amps. Notice i said coils "or" other components.


" I take from this that each coil must be able to handle the full current before the waveform transitions to the other half cycle and the other coil takes over. "

____ I-myself find that this wording should be clarified, as to exactly what's meant to be referred to by: "this", and by: "the full current" .

MM
"this"= discussion in first paragraph. "full current" in this case means 10amps limited by the fuse. You seem be suggesting it could be much more. This is where your experience comes into play.


" It is probably important to consider that an advantage in the original design is that each half of the stator coils conduct for only 180 degrees of the 360 input, consequently they get a rest between conducting half cycles. "

____ I'm finally relieved that you've now used wording which outwardly agrees with that which I've been proclaiming all-along, (and not seemingly in opposition, as of recently) !

MM
I don't remember you making this proclamation, but if you did, I clearly agree.


" Elsewhere it has been stated that if the 10-amp 6 volt 60 watt alternator is converted to 12 volts it will still only produce 60 watts but now at 5 amps.
I think this idea comes from the coils being in parallel with one another. "

____ I think it was Jim (for one) who may've declared that logical conclusion.
However in such case, the alt.stator need not be converted... as only the battery & system-loads would then need to be converted to equivalent 12-volt items, (along with the black-box's wire-wound resistor & possibly 'C1').

MM
Let's stick to the issue. It is a logical conclusion if you think the stator coils in the stock system are operating in parallel. but due to diode switching, they are not.


" The general rule is that current in parallel is additive, so the thought here is that if the max is 10, then they must each handle 5. This rule would apply if they were conducting at the same time, but they are switched by the biasing of the diodes so that their current is never added together, it is always one coil and diode conducting while the other is not, then switching with the changing of polarity. So they are taking turns and each provides all the current to the system during it’s turn. "

____ All that wording really can't be faulted (or confirmed) since it seems that you may have purposely stopped-short of stating the related figures, so that checking of your logic couldn't be done !?
So I think it needs to be asked/confirmed whether you mean to indicate that two (for example)- 5-amp half-wave pulses both occurring at once, is 10-amps total,, while two (for example)- 10-amp half-wave pulses occurring alternately, is still only 10-amps total,,
or just exactly whatever you actually mean specifically.
And to help others follow-along, please relegate your examples to JUST the stock SIX-volt n-c system only, (as your posted diagram pertains to).
I'm asking for such clarification in hopes that it will be presented with wording that's correlated with your wording above, however with all related figures included along-with.

MM
Bob. I read it again and can't seem to see fault. each of your blended questions are addressed. If a re-read still leaves you confused, please separate each question you don't understand.

" Also elsewhere it has been stated that the wattage rating is optimistic. "

____ If it was myself who ever used wording which indicated that as likely, then I would've meant to state-so only in relation to it's 'average-output' (during normal intended use of the engine while near regular speeds).
I think the '60-watt' rating is a probably a maximum acceptable amount that could be achieved without exceeding acceptable reliability.
I also think that Ducati had figured-in that their 6-pole alternator's 2 pairs of core-coils were about on-par with their 4-pole alternator's twin core-coils, and so the extra 50% of power (60 vs 40w) was achieved mainly due to the 50% increase in frequency (due to the 2 additional poles).

MM
Yes, I think it was you who I was referring to. I think you mentioned that 30 watts was more realistic. Bob if it spent most of it's time producing only 30watts under normal riding, you would be dead in the water at the end of the day.


" But if you figure 35 watts for the headlight, 10 for the ignition and 10 for running/brake and the system can keep your battery well charged under normal use, then it must be providing around 60 watts. "

____ I'm sure that's not a fair assessment...
Only constant loads such as ignition & running-lights, and even the battery & regulator consume power-juice at a rather steady rate, and that's all the alternator's power has to balance against,, while the horn & brake-light merely use the same current-juice which the battery had already taken-in.

MM
so state what a fair assessment is. I was not considering and did not state turn signals, or horn. I think you will see mention of the battery in my discussion and in fact it is included in the drawing, so don't know why you keep insinuating that I am not considering the battery. If it were at say 30 watts, the battery would in pretty short order be acting as a load.

the whole purpose of the discussion is to examine and refute the notion that the wattage rating would remain the same when altering the circuit as described to produce 12 volts. This owed to the understandable mistaken notion that the stators were operating in true parallel fashion. I don't know what the wattage rating is, but logically it must be more than 30 watts. Add the loads and see that the battery remains well charged tells you it is approaching 60watts if not exactly that.

regards,
Mike



Fun-Cheers,
-Bob

DewCatTea-Bob
Posts: 2897
Joined: Sun Nov 01, 2009 10:53 am
Location: Near SE side of Lake Michigan

Re: Can stock alternator produce more volts and power?

Postby DewCatTea-Bob » Sat May 14, 2011 8:13 pm

____ After reading-through Mike's complete post, I first have to make mention that, (just as seems to happen every so often with Mike's own interpretation of my chosen wording), this post of his has particularly notable misconceptions (of various concepts, of which my previous wording ought to have been clear enough to have properly grasped).
____ Note that the highlighted/shaded areas are sections which Mike had chosen from my-own previous-posts, for reference purposes.


DewCatTea-Bob wrote:MM
" I thought your examples pertained to the present real world situation. "

____ Yes, while indeed I prefer to remain in the "real world" -(as it directly relates to Ducati-circuits), I did in that case jump onto YOUR wagon -(constantly proclaiming that the alt.stator set-up is just the same as a center-tapped transformer set-up), and assumed that such an example (as I gave) would be understood as a non-center 'center-tapped transformer'.
MM
" as each stator coil must experience different loads as one must experience if first. they may be the same on the next cycle, but since they don't conduct at the same time, one must be first, so they do see different loads. If truly in parallel, they would see the same loads at the same time. "

____ That's of course all true and reflects the training of an electronic-tech schooled in the fine-art of micro-electronics,, but dare I say, that the fact that the very-first half-cycle (of a P.DC power-supply) see's a higher load (for about 120th of a second) before all the following half-cycles (see the same load), is pretty-much irrelevant to a Ducati charging-system ?


"MM
" I guess you are agreeing that they are robust and can handle 10 amps. Notice i said coils "or" other components. "

____ Of course Mike, I had realized your wording included the diodes (& all else).
(Please understand that my response-statements & comments are never really intended to be in opposition to any of your quoted wording, unless I specifically state so !)


MM
" "this"= discussion in first paragraph. "

____ Right, I had figured that much ! _ So still left wondering if there was any particular part of that, which ought to have been specifically concentrated on (in order to properly get the intended point).


MM
" "full current" in this case means 10amps limited by the fuse. You seem be suggesting it could be much more. "

____ I actually didn't mean to.
Thanks for confirming your expected figure.



DewCatTea-Bob wrote:By: MotoMike...
" Elsewhere it has been stated that if the 10-amp 6 volt 60 watt alternator is converted to 12 volts it will still only produce 60 watts but now at 5 amps.
I think this idea comes from the coils being in parallel with one another. "

____ I think it was Jim (for one) who may've declared that logical conclusion.
However in such case, the alt.stator need not be converted... as only the battery & system-loads would then need to be converted to equivalent 12-volt items, (along with the black-box's wire-wound resistor & possibly 'C1').
" MM
Let's stick to the issue. It is a logical conclusion if you think the stator coils in the stock system are operating in parallel. but due to diode switching, they are not. "

____ Now it seems to me that we are getting into something I can actually disagree with...
While it's fairly clear that the two alt.coils are in parallel PHYSICALLY, it's still fairly questionable whether they are "operating" in 'parallel', since only one at a time is providing current-output ! _ (Now continuing-forth assuming I have Mike's notion right.)
__ I believe that you are still thinking conventional-electronics -(with film-caps & other micro-tronics irrelevant to large current-capacities)...
While it's certainly true that the two separate currents as supplied canNOT combine to become the sum-total of both at the SAME-time (since the life-span of each are separated by 120th of a second), that doesn't mean that their sum-total is not available for use by the load-system ! _ (Once again, I declare that ya ought rather think in 'watts', and not just in 'current-amperage' !)



DewCatTea-Bob wrote:By: MotoMike...
" The general rule is that current in parallel is additive, so the thought here is that if the max is 10, then they must each handle 5. This rule would apply if they were conducting at the same time, but they are switched by the biasing of the diodes so that their current is never added together, it is always one coil and diode conducting while the other is not, then switching with the changing of polarity. So they are taking turns and each provides all the current to the system during it’s turn. "

____ All that wording really can't be faulted (or confirmed) since it seems that you may have purposely stopped-short of stating the related figures, so that checking of your logic couldn't be done !?
So I think it needs to be asked/confirmed whether you mean to indicate that two (for example)- 5-amp half-wave pulses both occurring at once, is 10-amps total,, while two (for example)- 10-amp half-wave pulses occurring alternately, is still only 10-amps total,,
or just exactly whatever you actually mean specifically.
And to help others follow-along, please relegate your examples to JUST the stock SIX-volt n-c system only, (as your posted diagram pertains to).
I'm asking for such clarification in hopes that it will be presented with wording that's correlated with your wording above, however with all related figures included along-with.
" MM
Bob. I read it again and can't seem to see fault. "

____ (Here's one of the misconceptions I referred to.) ...
__ Mike, what "fault" ?? _ I mentioned no faults (within your quoted wording) ! ...
My wording: "can't be faulted", was intended to state that (without any included figures), your (presented/quoted) wording can-NOT be faulted (OR confirmed) as to being correct (or not).


" each of your blended questions are addressed. "

____ I gather you're saying that the two examples I gave have already been addressed by you. _ And I agree that that's no-doubt true since I got those notions from your-own wording.
But I just wanted confirmation that they were as you'd agree, before further discussion of the reasoning behind those conclusions.


" If a re-read still leaves you confused, please separate each question you don't understand. "

____ I haven't been confused exactly, (since errors & omissions aside, I believe I've always understood your wording). _ It's just that I'd like confirmation that I've correctly understood you, before I next go-ahead with my notions of disagreement. _ That's all !


" MM
I think you mentioned that 30 watts was more realistic. Bob if it spent most of it's time producing only 30watts under normal riding, you would be dead in the water at the end of the day. "

____ That another misconception on your part Mike ! - (And a 'bass-ackwards' one, at that !) ... And it's disconcertingly disappointing that you've seemingly committed to memory your misconception of my past wording, as well, too ! _ (Plus, how could you think that someone like me could possibly really mean such a stupid conclusion ?)
__ Since this thread is concerning related subject-matter, I'll restate what I had meant to convey before when I had mentioned "30-watts" (in regards to the '60 watt' alt.)...
While I certainly never meant to indicate that it's only good for just 30-watts, I did mean to suggest that each alt.winding (alone!) supplies (the) 30-watts, (that's to say each one by itself, not totally !).
Also, it seems despite my extended -(clarifying) wording, you must still not have understood when I was making the logical deduction of whether Ducati rated their 60-watt alternator with or without the half-power, -(I used half "power" instead of half 'wave' just for your benefit, Mike). ...
Meaning that we are possibly left two deductions,, whether it was a 120w.alternator rated-down to 60-watts because of the half-power rectification, OR, a true 60w.alternator.
And I had meant to point-out that if it was the 60w choice, then after the half-power rectification, we'd then only have just 30-watts left, which I had logically deduced could NOT be the actual case ! _ (And then you came-along using the same logic back at me, as if I had concluded just the opposite of what my wording had meant to convey ! - [Now that's a sure example of bass-ackwardsness, if there ever was!].)
__ Now certainly of course I agree that if the engine continually ran at an RPM which left the alternator producing exactly 30-watts at all times, (rather than along-with periodic RPM increases, to keep the battery charged-up),, then with the power-loads all drawing current-juice, the battery would become discharged to the point that ign.spark would become too weak to continue-on ! ... Of course !! _ (You should've known better than to think that I'd need to have such a point made for me !)
This is one of those examples when, if it doesn't make good-sense (when it ought to), then it ought be considered that ya -(whoever the reader) probably didn't read the wording properly/correctly (so as to perceive the ACTUAL intended thought).



DewCatTea-Bob wrote: By: MotoMike...
" But if you figure 35 watts for the headlight, 10 for the ignition and 10 for running/brake and the system can keep your battery well charged under normal use, then it must be providing around 60 watts. "

____ I'm sure that's not a fair assessment...
Only constant loads such as ignition & running-lights, and even the battery & regulator consume power-juice at a rather steady rate, and that's all the alternator's power has to balance against,, while the horn & brake-light merely use the same current-juice which the battery had already taken-in.
" MM
so state what a fair assessment is. I was not considering and did not state turn signals, or horn. I think you will see mention of the battery in my discussion and in fact it is included in the drawing, so don't know why you keep insinuating that I am not considering the battery. "

____ I don't think I ever 'insinuate', Mike. _ If I had meant that you-yourself don't ever consider the battery, then I would've clearly indicated so !
And besides, it's quite clear that your quoted wording indeed included the battery as a load !
__ The stock running-lights & ignition are probably about 40-watts, while the current-draw of the battery varies depending on size, charge-state & overall-condition, (not to mention the effect from alt.RPM),, so I'd figure between 2 to 15 watts of power-consumption due to the battery alone.
__ But it ought be kept in mind that if the MAX.output rating of the alternator is 60-watts (at an ABOVE-normal/average RPM), then your given load-total assessment would have the battery discharging (to dead) during (extended) normal/average riding-RPMs, (when the alternator would be producing around 50 to 75% of that full-output).


" the whole purpose of the discussion is to examine and refute the notion that the wattage rating would remain the same when altering the circuit as described to produce 12 volts. "

____ That's something which ought might have been suggested (somewhat directly) under your new post-titling.
But where was such ever suggested, so as to then need to be refuted ?


" This owed to the understandable mistaken notion that the stators were operating in true parallel fashion. "

____ And where ever was it that such notion was thought or stated, that the twin alt.winding/diode outputs are in (or not in) parallel-operation ?
__ Anyhow, regardless of whether both are working-together in true parallel fashion, or alternately,, the end-result turns-out the same ! _ (At least in THIS particular case, if not in some other/similar [& irrelevant] circuit.)


" Add the loads and see that the battery remains well charged tells you it is approaching 60watts if not exactly that. "

____ I've just explained how that can-not be expected, (if 60-watts is the alternator's upper-range limit) ! _ Cuz if it's upper-limit (near red-line) is around the 60-watts, then if the load-total was near the same amount, then down near more normal/average rinding-RPMs, the alternator would then not satisfy the total-load.


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

MotoMike
Posts: 487
Joined: Wed Aug 04, 2010 3:40 am

Re: 6volt or 12 volt?

Postby MotoMike » Sun May 15, 2011 3:13 am

That's something which ought might have been suggested (somewhat directly) under your new post-titling.
But where was such ever suggested, so as to then need to be refuted ?

Bob. suggested in the 6 coil in a nc post.

_ I have doubts that the alt.wattage-rating was much at all based on the amount of current that the coil-windings could properly handle.
The stock 6-pole 4-core/coil alternator was rated at 60-watts, (but that figure is much suspect, as it was not stated as being produced at any particular RPM).
If that rating is trusted, then that could be either 10-amps @ 6-volts or 5-amps @ 12-volts.
Another involved mystery is that the stock charging-system only uses half of what's available from it's alternator, so then we might be led to think that it only supplies 30-watts of charging-power,, but we know that can't be the case because the stock load-system can consume more than that amount and yet the battery always remains well charged !
__ You seemed to have overlooked a basic error...
If each of the two alt.windings were to be producing 6-volts & 5-amps (6v x 5a = 30w x 2 = 60w total,, AT some particular RPM), then putting the two in series would provide 12-volts but still just 5-amps, and that does NOT "double the wattage" , (12v x 5a = 60w) !

MotoMike
Posts: 487
Joined: Wed Aug 04, 2010 3:40 am

Re: 6volt or 12 volt?

Postby MotoMike » Sun May 15, 2011 3:20 am

" This owed to the understandable mistaken notion that the stators were operating in true parallel fashion. "

____ And where ever was it that such notion was thought or stated, that the twin alt.winding/diode outputs are in (or not in) parallel-operation ?
__ Anyhow, regardless of whether both are in true parallel fashion, or not,, the end-result is the same ! _ (At least in THIS case, if not in some other/similar [& irrelevant] circuit.)

It wasn't stated, but the conclusions made where current's of the two stator coils were added together to equal the circuit max could only be logically arrived at if they were truly parallel. it is also possible that ignorance of the properties of parallel and series circuits is responsible as well.

DewCatTea-Bob
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Location: Near SE side of Lake Michigan

Re: 6volt or 12 volt?

Postby DewCatTea-Bob » Sun May 15, 2011 3:43 am

MotoMike wrote:DCT-B
But where was such ever suggested, so as to then need to be refuted ?

MM
" Bob. suggested in the 6 coil in a nc post.?

DewCatTea-Bob wrote:The stock 6-pole 4-core/coil alternator was rated at 60-watts, (but that figure is much suspect, as it was not stated as being produced at any particular RPM).
If that rating is trusted, then that could be either 10-amps @ 6-volts or 5-amps @ 12-volts.
Another involved mystery is that the stock charging-system only uses half of what's available from it's alternator, so then we might be led to think that it only supplies 30-watts of charging-power,, but we know that can't be the case because the stock load-system can consume more than that amount and yet the battery always remains well charged !
__ You seemed to have overlooked a basic error...
If each of the two alt.windings were to be producing 6-volts & 5-amps (6v x 5a = 30w x 2 = 60w total,, AT some particular RPM), then putting the two in series would provide 12-volts but still just 5-amps, and that does NOT "double the wattage" , (12v x 5a = 60w) !

____ Thanks for troubling yourself to find my past wording, Mike. _ But I still stand by it as completely correct ! ...
I think you thought it should be "refuted" apparently because you've somehow misunderstood. _ And I'd guess that the misunderstanding is that while I was still remaining in reference to the stock "half-wave" -('half-power', if you now prefer) rectification-process,, YOU (on the other-hand) must've assumed that I was ALSO jumping-upward to FW-bridge rectification, as well (as to the higher [12v] voltage). And that -(double-combo jump) just was not the actual-case which I was really in reference to, (I'm sorry to inform you) !
(But at least it's been a good exercise for all brains involved.)


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

MotoMike
Posts: 487
Joined: Wed Aug 04, 2010 3:40 am

Re: 6volt or 12 volt?

Postby MotoMike » Sun May 15, 2011 3:48 am

I believe that you are still thinking conventional-electronics -(with film-caps & other micro-tronics irrelevant to large current-capacities)...
While it's certainly true that the two separate currents as supplied canNOT combine to become the sum-total of both at the SAME-time (since the life-span of each are separated by 120th of a second), that doesn't mean that their sum-total is not available for use by the load-system ! _ (Once again, I declare that ya ought rather think in 'watts', and not just in 'current-amperage' !)

MM
First bob, why are you introducing components that were never mentioned by me and even some with names you made up? talk about irreleveant. Second, I have worked on systems that have current capacities that would turn the ducati single into plasma and not even slow down. You keep speaking of conventional electronics as incapable of comprehending the ducati electrics. Bob, they aren't that complex. 120th of a second is very slow in the field of electricity. your suggestion about thinking in watts makes me question your thinking. I can think in watts,volts, amps, resistance etc. I know that they are related.

let me get this straight. you acknowledge that the two coils can't be added to produce the sum total, but the say that the load system can draw on the sum total. if it cant be summed why not just say total?. Sum means add. lets just say total and then I will agree. If the loads are using 50 watts, then that is available, first from one half of the alternator and then from the other sequentially.

DewCatTea-Bob
Posts: 2897
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Location: Near SE side of Lake Michigan

"True Parallel" vs. Opposing-phased Charging-pulses

Postby DewCatTea-Bob » Sun May 15, 2011 4:33 am

DewCatTea-Bob wrote:By: MotoMike...
" This owed to the understandable mistaken notion that the stators were operating in true parallel fashion. "

____ And where ever was it that such notion was thought or stated, that the twin alt.winding/diode outputs are in (or not in) parallel-operation ?
__ Anyhow, regardless of whether both are in true parallel fashion, or not,, the end-result is the same ! _ (At least in THIS case, if not in some other/similar [& irrelevant] circuit.)
MM
" It wasn't stated, but the conclusions made where current's of the two stator coils were added together to equal the circuit max could only be logically arrived at if they were truly parallel. "

____ At this time I'm lost as to exactly what context we're in regards to here but, to help clarify some related facts, I'll next offer the following...
__ It's understood that if the two alt.windings were kept in parallel AND in-phase as well, thus both producing their half-cycle (5-amp) power-pulse at the very-same time,
then their combined-total would certainly without doubt add together (for 10-amps total), BUT only for the length of time of that half-cycle ! _ And during the next half-cycle, there would then be zer0 output,, thus the average-output would still continue to be just the same 5-amps !
So now I ask you, what bottom-line difference does it make whether the two pairs of alt.winding & diode combos have both their outputs occurring in "true parallel" simultaneously at once together, OR, alternately just one at a time ?? _ As with either type of occurrence -(the combined 10-amp pulse OR the singularly-occurring dual of 5-amp pulses), ya still end-up with the same amount of charge put into the battery, either way, (during that time-length of the life-span of the original AC-cycle) !


" it is also possible that ignorance of the properties of parallel and series circuits is responsible as well. "

____ Do you really think so ?
I-myself have perfectly understood the differences of parallel & series circuits since the early-60s ! _ (Even figured-out how to circuit four 8-ohm speakers so as to end-up with 8-ohm total impedance, all on my own way back then.)




MotoMike wrote:By: DCT-B
I believe that you are still thinking conventional-electronics -(with film-caps & other micro-tronics irrelevant to large current-capacities)...
While it's certainly true that the two separate currents as supplied canNOT combine to become the sum-total of both at the SAME-time (since the life-span of each are separated by 120th of a second), that doesn't mean that their sum-total is not available for use by the load-system ! _ (Once again, I declare that ya ought rather think in 'watts', and not just in 'current-amperage' !)

MM
First bob, why are you introducing components that were never mentioned by me and even some with names you made up? talk about irreleveant. "

____ Of course such is irrelevant, and that was an intended point.


" Second, I have worked on systems that have current capacities that would turn the ducati single into plasma and not even slow down. "

____ Wow,, in that case, I'd expect that storage-batteries may be involved, and if so, you then ought to realize what I've been expecting you to, all-along !


" You keep speaking of conventional electronics as incapable of comprehending the ducati electrics. "

____ That's of course silly, and just a notion which you came-to on your-own.


" Bob, they aren't that complex. "

____ What isn't ? - Charging-systems ? _ Well of course not, so why make such a point as that ? _ Are you really thinking that that needs to be pointed-out ? ...
(I think your frustration is behind the motivation to type such uninformative statements.)


" 120th of a second is very slow in the field of electricity. "

____ 'No, ya-think?' - Well so-what ? - That figure was not meant to be impressive, just that which ought be expected near idle!


" your suggestion about thinking in watts makes me question your thinking. I can think in watts,volts, amps, resistance etc. I know that they are related. "

____ Of course you apparently ought to, (which is why I suggested doing so),, but then you should understand that current (or voltage) is irrelevant (by itself) to the total-AMOUNT of electrical-juice (technically measured in 'coulombs'), and that wattage is more directly proportional to what's being worked with (than merely current) !


" you acknowledge that the two coils can't be added to produce the sum total, but the say that the load system can draw on the sum total. "

____ Yes, that's correct, Mike ! - The two separate out-of-phase supply 'CURRENTS' can-not be added together to get the total current of their sum, ALL-AT-ONCE,
YET the load-system can still draw on their combined total supply, just the same as if they had indeed been available added-together (had they been produced concurrently) ! ...
Maybe we should go-forth all the way to thinking in coulombs !?
But I don't wish to get others further confused with technical-terms that ought not really be necessary. _ So since you & most others ought fully understand 'wattage', then I think I now need only add that you ought also consider 'TIME' into your figuring-process. _ As including TIME & WATTAGE should correlate to coulombs even more so (than just my given wattage suggestion) !
(As I now have come to think that perhaps your mind-conditioning -(training) to think in terms of: 'in-an-instant-of-time' , has possibly stifled your ability to see the WHOLE-picture over time.)


" if it cant be summed why not just say total?. Sum means add. "

____ Yes, of course... Well while the out-of-phase half-cycle power-pulses can't be instantly added together since they don't both exist in the very-same 'instant-of-time', they do become added together afterwords, (since each one of themselves were not entirely consumed -(out of existence) as they were coming into existence, (unless of course ya don't consider them being stored within the battery).

____ (I'm tired now, and will have to come-back later to edit any [likely!] poor wording I've left here.)
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
Posts: 507
Joined: Sat Jan 01, 2011 12:57 pm

Re: 6volt or 12 volt?

Postby machten » Sun May 15, 2011 10:39 am

As interesting as all this esoteric debate is, please allow me to make a plea to both of you...

From the perspective of us uneducated "grunts" just wanting to rebuild our bikes, it's important to us lesser mortals to have access to you guys who clearly know so much. The worst possible outcome for the rest of us is that one of you eventually get's the the s&^ts and stops posting. So please don't turn this in to a "pissing contest" to see who can reach highest up the wall.

I say this only as someone who has something to lose through losing access to either of you. It's Ok to agree to differ.

Kev


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