White wire succses story!!!!

ok, so I'll need some higher wattage rated diodes for the 6v test. I'll pick them up tomorrow if i have time. I believe the ones i have are only rated to 1a, and as soon as i connected the 7v battery to the circuit, things started to get toasty.

ok, had battery reversed, lol. Reversed back to correct direction, tested again with 12v and got same results, increased resistance a bit so it was 175ma without, and 30ma with circuit, so 5.8 multiplier (worried about resistors handling extra current, so figured more in parallel would be less likely to die).

so, ended up with 60 idle, 125ma peak. So, 60ma * 5.8 * 6.6v = 2.3w idle, 125ma * 5.8 * 6.6 = 4.785w peak

So, to end up

Circuit P2P negative charging

12v circuit
Idle
0.175A * 13.9v = 2.4w
Peak
0.328A * 13.9V = 4.55w

6v circuit
Idle
0.348A * 6.6V = 2.3w
Peak
0.725A * 6.6 = 4.8w

I'll note that all of these were numbers tested tonight in one run, with the engine going the whole time, so they should be consistent.

So really, much of a muchness within reason... I think id be enclined to go with the 12v simply because of car parts, and ease of getting LED's etc for 12v circuits vs 6v?
 
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I have an educated hunch that there may be a sweet spot around 9 V,you might get 6W around there,which would be pretty good.I agree with you,it's safer to stay away from 6V, more current, chance of screwing up ign&higher diode losses.Would be interesting to find out how 8-9 cells would do.9V is an oddball voltage.Would have to craft your own batteries,not all that hard if you're a fanatic.Schotky diodes would help some esp at 6V,but have to be rated for 5Amp also.The low pulse duty factor leads to high peak currents,I think it's less than 10%, maybe 5 ish even.
I started a thread on LED's some time ago,'LED's the lowdown' or something like that.One thing to remember you can string them in series but paralleling them does not work well.they behave like diodes with a large offset voltage (2.5-3.5 V) but conduct with a vengeance above it ,so you have to control the voltage or use a power wasting series dropping resistor to stabilise the current (yuk).There is a power convertor around that turns a voltage source like a battery into a controllable current source ,which are what LED's need.It's called the buck puck (look google).I don't know what the power overhead of it is(suspicious).BTW there are fairly simple transistor circuits around that will do the same,not all that hard to build actually
There is a lot of LED lore around on his Forum,Sir Jakesus &Loquin are pretty knowledgeable,I am not really, in an application sense.
 
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ok, this is the end of the road for us?

Well, i might build a zener voltage regulator and use the existing circuit that comes with the drill battery charger (quite a small circuit with voltage sensing/overcurrent protection with LED indicator, uses zener + mosfets it would seem?)
- its 15v 400ma, so hopefully should work ok with a 15v zener circuit and around the 300ma charge, just a bit slower... what do you think d, will work ok? Dont want to overcharge my batteries and would like to have the ability to have the lights off rather than use them as a voltage regulator. I have a
1w rear brake light, will set up a series of led's in the brake light for my rear light, and I'll probably get/make a driver circuit (buck puck?) for a 3w Cree LED for my front light with a focusing lense set up. Should be plenty bright enough for my uses.
 
Yes, this is pretty much the end of the road,unless you have a hankering to try out an intermediate voltage battery.About nicads, if you approach full charge the batt.voltage goes up quite a lot I think to about 15V+ for a 12V battery.Not hard to come up with overvoltage LED based indicator using zener reference.What would you use the regulator for ?.This buck puck gizmo has only one output I think and is useful if input voltage goes all over the place,like with a rectifier circuit directly running off the WW.There are prob. better ways to set up a couple of controllable current sources using P channel mosfets or transistors using emitter current feedback, to play current source for LED circuits
As far as this project is concerned I could start another thread. 'WW, more succes stories' ,summarizing our findings, with do's & dont's,like don't fall for a fullwave rect.The basic thing limiting power output from WW,is the source resistance,lot's of voltage drop during high current pulse & the short pulse duration,however even if you could reduce R,you might then find that then the ign. starts to act up.You haven't had any problems with that as far as I know.May be someone will try a 9-10V battery & see how that plays.
 
yes, another thread is a good idea as it would be useful as this has actual numbers that people should be able to find. I will draw a circuit diagram for what i have done and attach it along with parts list that i used + costs if that would be helpful.

I might use a 3w Star luxeon LED as its cheap (15.90NZD, $7us roughly) - buck puck circuit is 23nzd if i want to buy one from the store i go to. As far as tail light goes, ill just series a bunch of leds and put the 1w led on an automatic switch on my front brake lever. That will be enough. I may set up two, for high beam since the buck puck can handle 4w iirc.

As far as the regulator goes from the actual AC charger, i thought it might be useful as it automatically stops charging when the battery is at full charge. It uses a mosfet, zener etc, with 400ma 15v in. However, im not sure i can get a zener with 5w at 15v, not from jaycar at any rate. Its a very small circuit, so not difficult to add onto the bike, but of course im unsure of the losses (shouldnt be too bad though?)

thanks for the help, has been educational + hopefully i can go somewhere from here. I'd like to make a voltage regulation circuit as well, perferably with a parts list that anyone can easily build and charge a 12v SLA from, as that would be a very useful thing for these engines. I think most people will want one, just knowledge stops them.

As far as the 9-10v battery goes, Im not sure how useful that would be considering we'd have to get odd parts or waste energy converting voltages for led's etc either down to 6 or up to 12v (i guess series 3.3v leds would be ok, but the higher power led's dont come in those sorts of numbers afaik). Ideally if we use 12v, a simple charging circuit with overload protection for SLA should be possible for someone with minimal skills.
 
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Fine with me,just mention what has proved to work best and refer to some of my posts if they want to dig deeper into the why's &wherefores.Tell them not to fool around with fullwave rectifying circuits.You prob. have a better feel of how LED's feature into the scheme of things.At least we did get something accomplished,you did a geat job!
 
As they say,'it takes two to tango' i.e. complementary attributes.I may have to go to Europe any time soon & be away from the MB scene for awhile.
 
It seems to me that that "white wire" is just a tapped part of the winding on the magneto.
That said, I'd use caution loading it down with a bulb, simply because it might tend to stress out the magneto, causing other problems.
I wonder if an exact schematic of the magneto windings can be had from the manufacturer, stating the design purpose of that wire.
 
in other threads, it has been dissected. Cant think of it off the top of my head, but yes it is part of the magneto. Shorting the two wires entirely will result in turning the engine off. Assuming you're careful there shouldnt be any major problem. In my testing the engine did not react adversely to the white wire being used at all, and i was using it at full potential, it was charging my nicad battery. Still revved very freely with no issues.

Many others are using the white wire 'as is' to run a white wire incandescent bulb with no regulation without any issues. I will be careful to monitor my findings etc once i have it all going and report back if i have any issues with magneto/cdi failure.
 
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