Jack,
The answer to your question is simple. The "Reg/Rect" is actually two things in one box. The regulator has a control in the rectification through 3 MOS transistors or 3 Silicon Controlled Rectifiers (in a three phase reg/rect)but let's treat them separately. In a silicon diode, if you double,or divide by two, the current in it, the forward voltage drop changes by 19.4 mV. This is an insignificant voltage compared to the 0.6 to 1.0 Volt forward drop of this diode. The MOS or SCR , one of the three, must carry the full load of current during that winding's peak output. In our case that is about 28 Amps. So. if you parallel two inputs to the rectifier, all you are doing is tying that extra wire back out of the way. The regulator section still handles 28 amps nicely. The MOS or SCR in this now one phase rectifier handles the same current as when a three phase device, but carries it for a longer time each engine revolution. So. each diode dissipates more power. But, the MOS or SCR has a much lower voltage drop than a silicon diode, and for that low forward drop is a BIG transistor, so the power will be easily dissipated if the regulator is fastened to a good heat sink and is in the air stream.
So, when I said that I paralled two of the yellow input wires, I was just putting one out of the way, and it doesn't hurt sharing that outputs current between two control elements.
Norm Matzen
--- In st2_owners@yahoogroups.com, Jack Davidson <tdma@...> wrote:
>
> Knowing that this subject has been beaten to death, I still have one
> final question:
>
> If you double up one side of a 3-phase rectifier and put the other wire
> to the other side, I still cannot see how full output can be achieved.
> You now have one doubled rectifier. OK, that one will provide doubled
> current, probably ot as much as the original, but double what the
> three-phase current would be for one leg. However, the other rectifier
> input will still be considerably less than the current capacity of a
> single-phase rectifier. It seems to me that you have just cut your
> regulator output to something considerably less than what it had with
> the original rectifier/regulator. Actually, it's a bit more than 1/3,
> as the newer 3-phase systems have more power output than this old one,
> but it would still drop the output capacity.
>
> Someone explain to me what I'm missing, please. This is like any other
> AC or DC circuit, where any component that is rated lower than the rest
> will reduce the capacity of that circuit to its rating. I'd love to
> have a MOSFET regulator, but not at the expense of losing system capacity.
>
> Jack in NY
>
> On 10/20/2010 11:15 PM, Michael Heth wrote:
> > [Attachment(s) <#TopText> from Michael Heth included below]
> >
> >
> > On Oct 20, 2010, at 4:34 PM, alasdair cameron wrote:
> >
> > >
> > > Soldering Caution!
> > > One thing to bear in mind with modern automotive connectors is that
> > > an inherent feature on a crimped spade type connector (inside the
> > > connector blocks) is a strain relief function. This is the extended
> > > tang at the end of a connector tab that grasps on to the insulated
> > > portion of the wire end.
> > > I am not an expert on this but have enough knowledge to know that
> > > vibration (not that our Dukes would do that!) and non compliant
> > > joints (soldered) might actually be more problematic than the
> > > connectors they replace which do allow for a certain amount of
> > > compliance. Vibration and fatigue go hand in glove so this is
> > > definitely a real possibility here, particularly if we are putting
> > > serious mileage on our mounts.
> > >
> > > Any electrical design engineers (applied) out there have any
> > > comments to add?
> >
> > Hey Kids,
> >
> > I had meant to chime in on this earlier but was either swamped with
> > getting prepped for the La Ducati Day or trying to recover from the 18
> > hour Sunday episode. Of course it was (ahem) rained out. By that I
> > mean it looked like it might rain and there was a little mist and
> > maybe a few drops and their attendance was down about 90% from last
> > year. I guess I know where all those ads for Ducatis that "has never
> > been ridden in the rain" come from. (If you did attend [and can prove
> > it] please contact me, as I am going to work up a pin in a similar
> > vein to the SF Giants Croix de Candlestick, a pin given to Giants fans
> > who used to tuff it out to the end at late freezing cold games at
> > Candlestick Park). This will be given to riders who make it to a rally
> > or event that has less than vacation postcard worthy weather, working
> > title is "WeenieNot".
> >
> > Anyway, I was going to say that hard soldering connections is a decent
> > way to go -
> >
> > **IF** you have good soldering skills and good equipment. Soldering a
> > good joint is a skill, it is not going to get you anywhere if you
> > don't know what you are doing. If you do 10 solder joints and one of
> > them is a cold solder, you're going to be playing "mister
> > troubleshooter" for a while until you sort things out, probably along
> > the road somewhere with a mini-maglite as your only friend. The
> > vibration problem mentioned will find the weak cold solder joint and
> > (well, you can figure the rest out).
> >
> > In my (not humble at all ) opinion, -> for the layperson,
> >
> > the best way (and the cheapest way) is to use a high quality crimper
> > and change out any craptastic OEM male/female terminations for 3M
> > quick disconnects which make such a good connection that they are
> > actually a bear to get apart again (they must have had a big laugh
> > around the conference table when they said, "yeah, let's call them
> > *quick* disconnects").
> >
> > The cheapest *high quality* crimping tool is a multi-terminal Klein,
> > they make about 3 that are all really very good. If you have a bunch
> > of bikes and want to work your way through them upgrading the
> > circuits, then I would recommend a Paladin ratcheting crimper. They
> > have interchangeable dies but they always have a model with the proper
> > insulated terminal dies included. You can adjust the ratchet mechanism
> > to only release when a full proper crimp has been done and then as you
> > work your way around you have the assurance you have made a good crimp
> > because it will not release until you have squeezed hard enough (they
> > do have a fail-safe release if you have adjusted it too tight).
> >
> > The above is for those who don't have (good) solder gear and skills.
> > If you know what you're doing soldering-wise (and have the gear) of
> > course you are in a different group.
> >
> > Personally I would not solder my connections because I have the
> > crimpers (geez, I think I have like 10 specialized crimpers) and
> > terminals to do it "solderless" and the idea of unsoldering a
> > termination is not on my list of things I want to do.
> >
> > I am very biased on the above advice as I will be selling the Klein
> > and (a decent knockoff off of) the Paladin on my site as soon as I get
> > around to listing them. But since I walk my talk the above is actually
> > kinda good advice.
> >
> > The wacky multi-pin somewhat weather-resistant connectors are another
> > story but in my experience they are only used for ancillary circuits,
> > not for "stop your bike along the side of the road" kind of circuits.
> > Cleaning and tightening the female side of the pins seems to work well
> > (as is the case with all females they prefer a really nice tight
> > interference fit).
> >
> > On my bike I had one that was intermittent on the tailight (not the
> > brakelight). My cut to the chase was to run another lead from my
> > fuseblock to the tailight termination.
> >
> > (as Otis out it so succinctly) "Walla" tailight is on and who cares
> > where the problem is, let's go for a ride.
> >
> > Thanks,
> >
> > M./
> >
> > Michael Heth
> > mheth@... <mailto:mheth%40motolectric.com>
> > (415) 992-7840 begin_of_the_skype_highlighting (415) 992-7840 end_of_the_skype_highlighting
> >
> >
> >
> >
>
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