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And now a widecase rectifier regulator question...


I have a narrow case bike, and the narrowcase stock regulators are hard to find and are even mor primititive than the widecase equivalent units.


The widecase rectifier/regulator units have the following six wires/connections:

1) yellow
2) yellow
3) red
4) red
5) brown
and
6) the case itself which is connected to the frame (ground.)


Clearly the two yellows connect to opposite ends of an AC winding.


Alos clear is that the case connect to frame ground.


The two reds I thought were the positive terminals, as very often one is shown connected to the battery in old Ducati wiring diagrams.

One of the reds though appears to be connected to a center tap on the coil whose ends are the yellow wires feeding the rectifier.

Can this rectifier/regulaort unit only be used with a center-tapped coil? I have a spare wide case unit and I was thinking about using it on my narrowcase. Is this possible?

Are the two reds internally connected?


What is the purpose of the brown wire?

[quote= JimF ...
" And now a widecase rectifier regulator question... "

____ There's about three different models of w-c.regulators and I'm going to touch-on the pre-1972 type now.
Of-course anyone-else (such as DucWiz) may include anything they see fit to add !



" I have a narrow case bike, and the narrowcase stock regulators are hard to find and are even mor primititive than the widecase equivalent units. "

____ First-off, I-myself don't consider the w-c.type regulator-units to be primitive at-all.
Both it and the n-c.type perform dual half-wave rectification.
__ Ducati never employed full-wave rectifiers between 1961 to 1975.

The widecase rectifier/regulator units have the following six wires/connections:

1) yellow
2) yellow
3) red
4) red
5) brown
and
6) the case itself which is connected to the frame (ground.)

" Clearly the two yellows connect to opposite ends of an AC winding. "

____ Not-REALLY ! _ That's the mistake that most-all ASSUME ! ...
Each of the yellow-wires each connect to their very-own separate alt.stator-winding !



" Alos clear is that the case connect to frame ground. "

____ Indeed so ! _ And importantly so !



" The two reds I thought were the positive terminals, "

____ That pair of red-connectors is actually a SINGLE terminal-point (conveniently physically located, only), and makes absolutely NO electrical-connection to ANY part of the unit !


" as very often one is shown connected to the battery in old Ducati wiring diagrams. "

____ That red-circuit is meant to connect both alt.stator-windings directly to the battery, so that the (half-wave rectified) alt.power can feed charging-juice to the bat.system.



" One of the reds though appears to be connected to a center tap on the coil whose ends are the yellow wires feeding the rectifier. "

____ While it may 'appear' as a 'center-tap', it's actually a (somewhat convenient) 'common' -(rather being a single-lead used to do the job of connecting BOTH alt.stator-windings to the battery) !!
(That logical-savings was deemed cost-productive to use only ONE/common wire-lead to do the job of connecting both alt.windings to a common-destination, [instead of a pair of red wire-leads],, and-thus has FOOLED many into assuming that Ducati was dealing with an ordinary center-tap affair !)
(See dual-pic.diagram below, to SEE the difference.)
__ For further distinguishment of the difference between the 'common' & 'center-tap' line-circuits, follow this link to another thread that covered the related issue... viewtopic.php?f=3&t=1438&start=10#p10150



" Can this rectifier/regulaort unit only be used with a center-tapped coil? "

____ While both the n-c & w-c R-R.units could also be used with a REAL center-taped alt.winding, they need-not be used only with such dual or twin alt.winding-circuits. _ And-so it's okay to feed just one of the w-c.unit's two input-circuits with the alternator's (one-pole grounded) AC.output !



" I have a spare wide case unit and I was thinking about using it on my narrowcase. Is this possible? "

____ Yes, it IS possible, (but probably-not for whatever you're considering at THIS time).
It can be connected to any alt.winding which has one of it's poles grounded, (as it only HALF-wave rectifies).
__ The w-c.type is more battery-dependent than the n-c.R-R.unit.



" Are the two reds internally connected? "

____ The two red terminal-posts are connected to each-other ONLY !!
However the red-circuit does connect positive-DC directly-to the battery/system (as like the n-c.unit), except pos.juice comes directly from both alt.windings instead of the rectifier-circuit (because the neg.output of the rectifier-circuit is grounded through the unit-casing).
(In the equivalent n-c.type circuit, the POS.output of the rectifier-circuit is what's fed to the battery, [because the equivalent red-common* is internally-grounded at the alt.stator].)
(* I recall the days back-when the term 'common' was more-used & better-understood than the term 'center-tap' was ! _ But it seems that's become reversed these-days, so people now-days instead use THAT c-t.term even-when they should rightfully state 'common'. _ I hope everyone now understands the-DIFFERENCE ! - [Otherwise, in another 50-years,, I wouldn't be surprised to hear people say 'center tap' when they actually mean 'ground'.])



" What is the purpose of the brown wire? "

____ The brown-circuit is for allowing the w-c.unit to 'sense' the system-voltage, and decide whether or-not to allow charging-juice into the system.
If the system-voltage is sufficient, it will then turn-on the w-c.unit's rectifier-circuit,, and when the system-voltage gets too-high, it then get's turned-off.
__ So the w-c.unit is in need of a fairly-charged battery, in-order to get turned-on in the first-place. - (A kind-of 'catch-22', if ya will,, [if your battery is as 'dead', or off-line].)
Also, once w-c.units have been run without a battery for a while with the lights on, their power-handling circuity gets burnt-open and then later becomes left in it's turned-off state.



DUCATIly,
-Bob

Hi Bob,

I have been waiting for you to finish...

You wrote:

"And-so it's okay to feed just one of the w-c.unit's two input-circuits with the alternator's (one-pole grounded) AC.output !"

That makes me think I could use a wide case R/R on the "lighting" whose other end is internally grounded, right

Later you wrote:

"So the w-c.unit is in need of a fairly-charged battery, in-order to get turned-on in the first-place.
Also, once w-c.units have been run without a battery for a while with the lights on, their power-handling circuity gets burnt-open and then later becomes left in it's turned-off state."

That makes me think I can't use the wide case R/R on my bike unless I implement a battery.

Jim

[quote= JimF ...
" I have been waiting for you to finish... "

____ It seems I can almost never get a post truly/completely finished, but when I think I've got it done, I then sign-off with X-Cheers, -Bob .
__ (In case you hadn't yet noticed, I also got my other thread-post [on LED.lights] finished [very-early this morning].)

"And-so it's okay to feed just one of the w-c.unit's two input-circuits with the alternator's (one-pole grounded) AC.output !"

That makes me think I could use a wide case R/R on the "lighting" whose other end is internally grounded, right

____ Right,, as any alt.power-coil that has one-end/pole grounded, can have it's opposite-pole connected to either of the unit's yellow-terminals. _ So the lighting-coil could indeed be utilized that way.
__ Furthermore, if you also grounded the other alt.power-coil (meant for ign.system), then that-circuit could be inputted into the unit's other yellow-input.

"So the w-c.unit is in need of a fairly-charged battery, in-order to get turned-on in the first-place.
Also, once w-c.units have been run without a battery for a while with the lights on, their power-handling circuity gets burnt-open and then later becomes left in it's turned-off state."

That makes me think I can't use the wide case R/R on my bike unless I implement a battery.

____ Correct,, as normally when the key-switch is turned-on, the battery is then connected to the w-c.unit (through the brown-wire), and if the battery has at-least near 4-volts, the unit is then 'activated'. _ And if the unit is-not activated that way, it then remains turned-off (and functionless same as one that's been internally-destroyed [by continued-running with the battery then-later disconnected] ). - (The unit protects itself from such burn-out by not being able to become activated without a battery connected in the first-place. _ But they still can get burned-out whenever the battery-connection becomes disconnected during lights-on operation.)
Unlike most-all other R-R.units, the w-c.unit can't be used with a large-capacitor (in place of a battery), because the cap will soon discharge after-running and-so won't be able to turn-on the unit for the next-time.
__ A n-c.type R-R.unit won't regulate system-power for your-purpose either, because THAT n-c.system much-depends on a normal-battery to do the ACTUAL voltage-regulation !!

____ Jim, has it not yet occurred to you that you could use most-any F-W.R-R.unit with your grounded lighting-coil, by not allowing your LED.light-circuits to become grounded at any point !?


Hopeful-Cheers,
-Bob

Any recommendations?


I found this one:

http://www.britcycle.com/products/332powerunits.htm



332-104/B Boyer Single Phase
Replaces Rectifier and Zener Diode
Plus Has a Capacitor for Running Without a Battery

[quote= JimF ...
" Any recommendations? "

____ Yes, the newer version of the old MityMax-unit on eBay, that I had posted a link to (and you should've already found if you've tried all the links I've meant for you to check-into).



" I found this one: "

____ Your link leads to a page that has a number of different units listed (with no prices),, but the particular model shown nearest the top of the page & first listed, IS the old Mity-Max R-R.unit that I'm familiar with, and would be especially functional since it includes a capacitor !



" 332-104/B Boyer Single Phase
Replaces Rectifier and Zener Diode
Plus Has a Capacitor for Running Without a Battery "

____ I'm not familiar with that particular model, but it or any-other single-phase unit with a capacitor should do you quite well enough. _ And considering your extremely-light duty-requirement, the cheapest available model should be way-more than good-enough, (even if a half-wave version possibly existed,, as even with just half the power, you'd still ALWAYS-have a vast oversupply of power with the added capacitor !) !
__ I suggest that you search eBay for a supplier who you can get quickest/assured delivery from.


Hopeful-Cheers,
-Bob

I have a problem with the MityMax:

It is a positive ground unit.

I cannot operate the LED dual-filament taillight in a positive ground configuration; The circuitry cannot be reversed biased.


I am continuing to look for an alternative...

[quote= JimF ...
" I have a problem with the MityMax:
It is a positive ground unit. "

____ How can you tell whether it's pos or neg.grounded BEFORE it's installed ??
In any case, you should understand that that's NOT any real problem (for TWO reasons) !! ...
__ 1st - Those type of R-R.units can be either polarity ! _ Although I understand that the new-maker dropped the name 'Mity Max', you should be able to find the new-version listed on eBay (and stated as EITHER positive or negative-ground applicable) !
__ 2nd - I thought that you've come-to realize that you'd avoid the 'ground' anyhow !? ...
By NOT actually grounding your LED.circuits (in attempt to acquire any power-circuit through the frame), then any would-be ground-polarity of the R-R.unit will then of-course be rendered IRRELEVANT (as far as the LED.circuits are concerned),, because NEITHER DC.polarity will be connected-to or run-through 'ground' !
__ Some cheaper-made R-R.units may use the unit's own metal-casing to connect the pre-intended ground-circuit,, but most good-quality units don't do that, and have completely-ISOLATED pos & neg output-leads. _ And of-course there's no law that requires that EITHER output-lead NEEDS to be grounded !



" I cannot operate the LED dual-filament taillight in a positive ground configuration; The circuitry cannot be reversed biased. "

____ But I thought that you-yourself had CHOSEN to ground their circuity !? _ To get around & away-from all-THAT grounding-concern issue,, you could easily AVOID 'ground' altogether, by simply ADDING/including a 'return-line'/wire so-as-to take-the-place of the regular ground-circuit through the frame !
So-then, just as you've already run a connection-wire TO the LED.lights,, you can ALSO run a SECOND (rather thin-gauge) 'return-wire' BACK-to the UNGROUNDED neg.output of the R-R.unit !!
Is this 'NO-ground' concept more-clear now ?



" I am continuing to look for an alternative... "

____ I'm sure eBay has whatever you wish !
Did you not before see the unit I had before left a link to,
or do you not wish to deal through eBay ?


Hopeful-Cheers,
-Bob

Bob,

If we think of current flow in the conventional way as going from positive to negative, the current to the high brightness filament and the current to the low brightness filament MUST flow in to those two terminals and the return current MUST flow out of the LED unit at the unified ground connection of the unit.

It's the circuitry. Connecting the base of the LED bulb to a positive frame and putting negative voltage onto the high brightness and low brightness inputs will reverse bias the circuitry and as such the LED unit will not work.



I will look for the negative ground version of the product.

Thanks for your help!

Jim

JimF wrote:Bob,

If we think of current flow in the conventional way as going from positive to negative, the current to the high brightness filament and the current to the low brightness filament MUST flow in to those two terminals and the return current MUST flow out of the LED unit at the unified ground connection of the unit.

It's the circuitry. Connecting the base of the LED bulb to a positive frame and putting negative voltage onto the high brightness and low brightness inputs will reverse bias the circuitry and as such the LED unit will not work.



I will look for the negative ground version of the product.

Thanks for your help!

Jim

____ BUT I THOUGHT YOU UNDERSTOOD THAT 'GROUND' WILL BE AVOIDED ! ??
Now that I've gotten the chance to have finished elaborating my prior-post, I expect that THE jest-thought has by-now 'clicked' in your head !?



[quote= JimF ...
" If we think of current flow in the conventional way as going from positive to negative, the current to the high brightness filament and the current to the low brightness filament MUST flow in to those two terminals and the return current MUST flow out of the LED unit at the unified ground connection of the unit. "

____ That's of-course an important point, IF the R-R.unit itself MUST be grounded (in any way) ! _ BUT WHY must the unit be grounded ??
If you find a commonly-available model/version, it can be mounted & used without ANY of it's DC.outputs connected to 'ground' !
__ I suppose that you had expected your posted-explanation to lead-to me replying with something like: 'OHH! I-see-now. Never-mind then, sorry !',, but, we're now supposed to be thinking 'OUTSIDE-of-the-box', Jim !



" It's the circuitry. Connecting the base of the LED bulb to a positive frame and putting negative voltage onto the high brightness and low brightness inputs will reverse bias the circuitry and as such the LED unit will not work. "

____ Well OF-COURSE ! _ Rather than think that I needed to be told that, you should've instead been thinking of what YOU must be overlooking (in order for ME to have been making any sense) !
__ You needed to get the thought of continuing to make-use of the "frame" (for the LED.circuits), out of your head ! _ (You must be TIRED in order to not have the simple concept dawn on you.)
Without use of a 'ground-circuit' through the frame, the R-R.unit's pos & neg.output wire-leads can be connected whatever-way you CHOOSE ! _ (And I sure don't think you'd possibly get THAT wrong !)



" I will look for the negative ground version of the product. "

____ You should finally be understanding that it doesn't really matter which ground-polarity version you might get, because you CAN'T ground EITHER output-pole of the R-R.unit ANYHOW, (if you're going to use the already 'grounded' lighting-coil) !
You just need a R-R.unit that has a pair of AC.inputs plus-also BOTH a neg.DC-output AND a pos.DC-output (both with-in isolated wire-leads) !
__ The old MityMax-model/units I've used were like that, and the installer-himself was always left with the self-decision of whether to wire-up the output-connections for either pos.ground OR neg.ground !
If you get a R-R.unit-model with either it's pos.output or it's neg.output grounded only through it's metal-casing (and-thus left with just-ONE DC.output-wire), THEN you'd have-to isolate the unit-case from ground ! _ But ONLY-because of the grounded power-coil (and not because of the LED.circuits), SINCE the DC.power to & from the LED.circuits is to be done through a PAIR of wire-leads, (and NOT JUST-one, as through a standard 'ground-circuit system') !



" Thanks for your help! "

____ But certainly OF-COURSE, Jim !
(But next-time you catch me while I'm in the actual-process of completing a post, please give me more time before you jump-ahead and presume my intended presented-conceptions.
__ Let me know if you still don't-get how the full-wave rectification process can possibly work with a grounded power-coil, and I'll then see-about drawing-up a scheme-diagram to explain it better.


Hopeful-Cheers,
-Bob