Light switch wiring dilema

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vintagetour
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Joined: Tue Dec 20, 2011 3:06 am

Light switch wiring dilema

Postby vintagetour » Sat Mar 17, 2012 1:12 am

Once again I am in need of some advice from the more experienced and from the looks of some of electrical topics there are some very knowledgeable people here on this forum. Subject is the same 67 250 scrambler Ser#102772 so wiring diagram is (250 Scrambler from e.n. 92172). The wiring diagram is pretty self explanatory until you get to the light switch. I am interested in how others have wired in the switch. I have a 7 wire, 3 position (1,0,2) with Hi-Lo toggle light switch. I don't have a horn or a parking light so those are just extras. I am puzzled as how to wire the hot wire from the battery (6 volts to the switch all the time) and the red wire from 3 wire magneto alternator. Does anybody have a working example they could check?
Thanks
Tom

JimF
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Re: Light switch wiring dilema

Postby JimF » Sat Mar 17, 2012 1:56 am

Hi Tom,

I would like to help but I personally am too confused to give you good advice right now.

The battery is a source of DC (Direct Current) power. The magneto alternator is a source of AC (Alternating Current) power.

Either power source could be used to power the lighting, but you can't put both power sources to the switch as the two power sources are at odds with each other.

We'll all work with you to get this sorted. Can you give me a link to the wiring diagram you are using?

Jim

vintagetour
Posts: 32
Joined: Tue Dec 20, 2011 3:06 am

Re: Light switch wiring dilema

Postby vintagetour » Sat Mar 17, 2012 3:25 am

:D Thankyou, Thankyou, Thankyou Jim! That is exactly what I have been saying since I looked up this wiring diagram. I skipped telling the part about all the turmoil I went through trying to figure these electrics out {and they make fun of Lucas). I even temporarily jumped those two power sources only to confirm that it drains the battery quicker than you can say howdy. I instead added another diode and connected the red wire from the alternator to the battery (the white wire from the alternator is already assigned this duty) to help it keep up with the load when lights are turned on.
I will try to figure out a way to post a picture of the wiring diagram (Ducati Work Shop Manual) so everyone can be as confused as you and me Jim. I was just hoping there was something I was missing and someone would say "Hey Dummy, all you have to do is this..." I can read prints but I have to admit I don't understand all I know about electrics :lol:

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

Re: Light switch wiring dilema

Postby DewCatTea-Bob » Sat Mar 17, 2012 12:05 pm

vintagetour wrote:Once again I am in need of some advice from the more experienced and from the looks of some of electrical topics there are some very knowledgeable people here on this forum. Subject is the same 67 250 scrambler Ser#102772 so wiring diagram is (250 Scrambler from e.n. 92172). The wiring diagram is pretty self explanatory until you get to the light switch. I am interested in how others have wired in the switch. I have a 7 wire, 3 position (1,0,2) with Hi-Lo toggle light switch. I don't have a horn or a parking light so those are just extras. I am puzzled as how to wire the hot wire from the battery (6 volts to the switch all the time) and the red wire from 3 wire magneto alternator. Does anybody have a working example they could check?
Thanks
Tom
____ Sorry that I haven't gotten to this sooner ! _ There's probably no one (at least here) who knows as much as I do about the stock wiring-scheme of your (1-year) Scr.model, as I have all Duke-model wiring systems pretty-much memorized.
__ Your Scr.model was made in late 1966 and quite possibly titled as a 1967-model.
It's the only n-c Scr.model which made use (smartly!) of a battery ! _ The battery was employed only for running the brake-light & parking-lights ! _ So if you don't care to wire-up everything as originally done as stock and-so don't care about having the parking-light feature, then you can skip your concerns about connecting the battery to the lights.
The red alt.wire-lead is intended to power the tail & head lights (with straight AC), and that wire-connection is the more useful one for you to get straightened-out.
__ It would be helpful if you could post any pictures you have of the switches you have for your project, so that I can be sure of what you have and can then better direct you, (as all too often, many have the wrong switches for there project).
____ So next, let me know exactly what you wish to get to next.


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

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

Re: Light switch wiring dilema

Postby DewCatTea-Bob » Sat Mar 17, 2012 12:28 pm

By: JimF...
" Either power source could be used to power the lighting, but you can't put both power sources to the switch as the two power sources are at odds with each other. "

____ Sorry to say but, while I won't declare that statement as outwardly 'wrong', it does seem at least somewhat misleading (if not actually not-correct), in two ways...
First, (for the Duke-model in question), the battery power-source could indeed power the lights BUT, the battery would not do so for very long, as it is only given a trickle-type amount of charging-power !
And second, the STOCK-switch does indeed accept (& directs) BOTH the DC AND AC power-sources !!


" We'll all work with you to get this sorted. "

____ I'm afraid to say that I'm possibly the only one who you really ought to pay full attention to, as others may not seem to agree with me and yet I'm the only one who I KNOW you can completely trust as being pretty-much totally CORRECT about the info I provide. _ And if I'm not exactly agreed with, you may then become confused trying to blend their info with mine.


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

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

Re: Light switch wiring dilema

Postby DewCatTea-Bob » Sat Mar 17, 2012 12:57 pm

" I skipped telling the part about all the turmoil I went through trying to figure these electrics out "

____ Actually, they're really quite simple ! _ But the drawn scheme-layout of the handlebar-switch (connected from within the headlight-shell) for controlling power to lights, can be confusing.


" I even temporarily jumped those two power sources only to confirm that it drains the battery quicker than you can say howdy. "

____ OH NO, you're not the first to do such a thing though ! _ That is bad-news for your alt.rotor! _ As each time such a circuit is made AND broken, the magnets of the rotor are then somewhat degaussed -(weakened).


" I instead added another diode and connected the red wire from the alternator to the battery (the white wire from the alternator is already assigned this duty) to help it keep up with the load when lights are turned on. "

____ Doing that COULD help keep the battery charged longer (while riding with lights turned-on), IF the (stock) switch allowed battery-power to route to the headlight, but a simple diode will not allow for providing enough DC-power to keep the lights at sufficient brightness (once the battery has discharged).
HOWEVER, this idea of using the battery to also run the headlight, will not be possible without rewiring the otherwise stock HL.switch connections !


" I will try to figure out a way to post a picture of the wiring diagram "

____ I may get that done myself soon. _ (It's already posted in a past thread.)


" I was just hoping there was something I was missing and someone would say "Hey Dummy, all you have to do is this..." "

____ Well you & I can next get to that end, but I first need to know if you wish to stick with the original/stock wiring-scheme, or what.


Duke-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

vintagetour
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Re: Light switch wiring dilema

Postby vintagetour » Sat Mar 17, 2012 2:02 pm

Bob,
Firstly I only jumped the wire across the switch long enough to see the volt meter take a nose dive (maybe 2 seconds). I still have good voltage from both the white and red wires coming off the 2 wire coil. And I don't care how the thing is wired. I started out wiring it as I found it, then wiring it like the wiring diagram (except for the jumper part) so I am ready for round 3 if that's what it takes to get it working properly. My bike is stamped 12/66 on the fork leg but I am calling it a 67 as you say. I have my drawing of how the switch is built but I don't know how to post it. Here is a pic of the switch shown in the "1" position.
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vintagetour
Posts: 32
Joined: Tue Dec 20, 2011 3:06 am

Re: Light switch wiring dilema

Postby vintagetour » Sat Mar 17, 2012 2:43 pm

Bob, Sorry I couldn't figure out how to finish my post after I added the picture. The black wire on the lower left is the 6v hot wire from the battery. I will call this the distribution post (C) as it distributes battery power to the other posts in all (1,0,2) positions. The tan wire on the right is I assume the tailight because when the switch is in the 2 position it powers the brown (D) and the (just below,call it B ) post (the one with the copper strip going up to the Hi-Lo toggle). This would give you headlight and tail light in the (2) switch position. The B post has no way to connect a wire to it. It is just connected to the cooper strip. Just below B post you can see (E post)the suspect red wire from the alternator (presently disconnected in the headlight) It looks like it is connected to B but if you enlarge the picture you can see it is turned left. The other post lower left (call it F) is under the yellow wire. There is a blue wire you can't see that is connected to that F post. It goes to the parking light I don't have (taped up). So in position (one) 6v power is going to 2 dead ended wires. Sorry to drag this out but I am trying to give you some identifying letters so I can follow your instructions. This is just how it is wired now. I will change per your instructions if needed.
Thanks in advance
Tom

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

Re: Light switch wiring dilema

Postby DewCatTea-Bob » Sat Mar 17, 2012 5:33 pm

" I only jumped the wire across the switch long enough to see the volt meter take a nose dive (maybe 2 seconds). "

____ As far as the rotor-magnets are concerned, it doesn't matter how long the stator is charged by the battery, with DC-current passing-through, it's only the moments when the circuit-connection is MADE & when it's broken-off, that the undesired effect on the magnets occurs.



" I still have good voltage from both the white and red wires coming off the 2 wire coil. "

____ That's good then.
__ The red alt.wire-lead (from the lighting alt.power-coil) is for running just the lights, while the white wire-lead (from the same stator-coil) is to feed a diode to then charge the battery.



" And I don't care how the thing is wired.
I started out wiring it as I found it, then wiring it like the wiring diagram (except for the jumper part) so I am ready for round 3 if that's what it takes to get it working properly. "

____ The stock wiring-system is not so bad really, so I suggest that you try going that way, and if you then don't like something about it, then later we can try whatever modifications you please.



" The black wire on the lower left is the 6v hot wire from the battery.
it distributes battery power to the other posts in all (1,0,2) positions. "

____ Well it's not supposed to be connected-up that way, as the black-wire & the terminal it's connected to are intended for the tail-light.



" The tan wire on the right is I assume the taillight because when the switch is in the 2 position it powers the brown (D) and the (just below,call it B ) post (the one with the copper strip going up to the Hi-Lo toggle). This would give you headlight and tail light in the (2) switch position. The B post has no way to connect a wire to it. It is just connected to the cooper strip. Just below B post you can see (E post)the suspect red wire from the alternator (presently disconnected in the headlight) It looks like it is connected to B but if you enlarge the picture you can see it is turned left. The other post lower left (call it F) is under the yellow wire. There is a blue wire you can't see that is connected to that F post. It goes to the parking light I don't have (taped up). So in position (one) 6v power is going to 2 dead ended wires. "

____ When the switch is set so that the tail AND the headlight are to be powered-on, the power-source is supposed to be from the red alt.wire-lead !
Also I believe the switch's '1' position is supposed to allow the battery (B+) to power the tail & the head-shell parking-lamp lights (regardless of whether the key-switch is turned-on)...
So the red wire at "E" is supposed to go to the parking-lamp, while the hidden blue-wire at "F" is supposed to carry the B+ power-source into the switch. _ So if you indeed have the switch pictured currently in position-1, then it correctly has the B+ connected to the parking-lights.
__ Position-2 would connect the brown-wire at "D" to the Hi/Lo input & the tail-light -(black-wire at "C"), so therefore we know that that tan/brown-wire is to be connected to the red alt.wire-lead (from the alt.cable coming out of the motor-case) !
__ Position-0 would only have the three loads all connected together, thus it's the OFF-mode !
____ Your statements of what's what threw me off a bit at first, so I had to take a bit longer to realize that those statements must have been ASSUMED by you rather than actually factual, and so I've come to realize that your posted declarations (of what's what) were quite misleading & incorrect.
I would've been able to straighten-out all the points sooner if you had merely posted your picture and left EVERYTHING-else for myself to state what all is actually what.
__ Well that's all of what I have done for you concerning the 4 wires & terminal-posts which you had brought-up. _ Let me know if you also wish confirmation of the functions of the remaining three wires, (and if so, then please post a pic of the TOP-side of your switch).



____ Perhaps you'd find this past thread of some interest (as it is mostly concerning your model & current topic). - viewtopic.php?f=3&t=61



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

vintagetour
Posts: 32
Joined: Tue Dec 20, 2011 3:06 am

Re: Light switch wiring dilema

Postby vintagetour » Sun Mar 18, 2012 1:41 am

Bob,
You weren't kidding when you said you had this system memorized :!: It all makes sense now. I do have one more question though. Do I need to remove the diode I installed from the red alternator wire? Will it restrict the current?
Tom


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