White wire succses story!!!!

[duivendyk]

As you can find out in my previous posts, it appears the theCDI only loads the positive cycle of the ignition coil output.What you load it with (via a diode) during the negative cycle does not affect it at all.The neg. cycle also has about 3 times the amplitude.So if the effect of any of any load is principally on that portion of the ac pulse.The ignition generator is a winding, one side is connected to ground and there is a tap on it for the WW,the end of the winding is the blue wire.Putting a load on the WW reduces the output, esp at low(cranking) speed ,when the output is low.The resistance to ground is 2.8 ohm,that does not seem like a lot,but it limits the available output power from the WW.

 

[skyl4rk]

It looks to me like you have put together a voltage doubler circuit?

The first diode and cap make a negative clamp and the second diode rectifies it into dc. If you put another cap across the battery it would be a textbook voltage doubler.

See last page of pdf. The pdf version shows a positive clamp plus rectifier to make a voltage doubler.

 

[duivendyk]

Correct,it is what is termed a voltage doubler circuit except that in this particular case the pos.&neg.cycles have substantially different amplitudes ,a 3 to1 ratio in fact due to the loading of the pos.cycle by theCDI unit.So the term 'peak to peak rectifier' is more apt.Note that we are not dealing with a continuous ac signal,but with a series of ac pulses,a cycle of ac followed by a relatively long duration,probably about 10 times as long,period of zero output, followed by the next ac pulse.So the actual pulse currents are quite large compared to the average current values.

 

[impression]

so, the reason for the 2nd pathway is to give somewhere for the excess power to run through so we don't blow up the battery/lights ect: ?

 

[duivendyk]

No,the peak to peak circuit provides more juice to the battery than the single diode cicuit would,it also hardy affects the ignition circuit when starting the engine.But it certainly does not prevent overcharging the battery,in fact since it will charge it faster,it would do the opposite.This is another issue and a bit of a red herring in my opinion.Look out for more info from
Etacovda,he has started a new thread summarising our results and will post schematics.

 

[impression]

Thanks D, my head's aching atm so yah, a schematic i could follow would be great as from there i could 'add in' as it were the extra's for my bike.

I just needed to be able to 'charge' as it were my 6v battery in turn i would then run my lights off it.

 

[duivendyk]

Imp,I think I have come up with a neat solution to what you're trying to do, if we can find out what kind of battery you have in your torch.
You would like to charge your 4.5 torch battery but also have more capacity by charging another battery.The WW likes to see a battery of around 8-10 V, then it will put out most power.OK we charge two ! ,4.5V batteries in series the one inside connected to one side of the outside battery and the other side connected to the peak to peak charging circuit when you are running in daylight.Now when you want to use the lights you switch the batteries around so that they are now in parallel making up a larger capacity 4.5 V battery then you turn the torch on (I assume it has an on /off switch).The taillight could be powered by the charge circuit in series with the parallel combination of the two batteries.It will take a double pole, double throw switch to switch the batteries around and another switch to do the tail light.This is not the only solution for the taillight there are other options.This circuit will be quite efficient,no power wasted in resistors.It sounds complicated but it's not that bad.Do you understand the basic idea?.It's not a good idea in general to put dissimilar batteries in parallel ,but if they are the same type and preferably also from the same manufacturer you can usually get away with it.

 

[impression]

http://www.sontax.com.au/promo/Magictorch.htm

that's my torch, it came with the rear light which is powered from the torch's DC out. I am unable to tell what the DC out voltage is.

Torch Internal Battery NiMH 2/3AA 600mAh 3.6v written on the battery. ( which is inside the torch, i believe it's isolated and just powers the torch just like any other battery would)

i don't have a multimeter though :/

here was my original plan.

http://www.motoredbikes.com/attachment.php?attachmentid=16025&d=1237126350

 

[MurraySabrePlus]

This might work...

 

[impression]

This might work...

WOW, that looks like it could be it

my engine is grounded to the frame through the mountings. ( well the frame is painted :S )