Sanity check: The lay of lighting coil (or any other stator coil for that matter

[tdpomodoro]

All,

Just a sanity check on the lay of lighting coil - thinking back to my introductory physics course:

1) Shouldn't matter if i start winding the bobbin right to left give the coil will produce AC (not the case for a pulser coil of course where initial polarity is key)

2) Be consistent with the direction of lay - wind the wire, say, right to left then run wire parallel to iron core back to right side of bobbin and repeat. (Winding right-left, then left-right etc will cancel out any voltage being produced.)

Learnt the hard way, or rather, my old man did. He wound a lighting coil for his PE400, i must admit with my instructions "it shouldn't matter how, just wind it all on". Wired it in today and got some inexplicable readings out of the multimeter - and barely enough juice to power a 12V 21W taillight bulb. Went back to the drawing board and thought a little more and reasoned the above points out - i think i've got it sussed.

[Montynut]

There is no need to run parallel on the return. You are winding a coil just wind across the width of the coil and then wind back across the width and so forth until the desired number of turns is reached.

It is naturally critical that you do not change the direction (cloackwise/antyi-clockwise) of the coil winding. The voltage does not build up layer upon layer but is the function of the number of turns in total that comes under the influence of rotating (moving) magnet field that generates the voltage (actually flow of electrons). The magnetic flux changes direction as the ‘N’ then ‘S’ poles pass over the coil hence AC.

Modern polyester coated annealed copper winding stock is very tough but if you are using the old style enamel insulated wire you need to be very careful with it to avoid shorted turns. That may have been the problem with the coil you previously wound. The number of turns is very inportant and you should have counted them on the way off or have some documentation to tell you how many turns required.

[tdpomodoro]

Thanks for your reply, Montynut. We never had an original lighting coil to work off unfortunately. We used the iron from an old pulser coil and an old ignition coil and sandwiched them together. Perhaps there's not enough iron.

I'm just digging out the PE400T manual now to get the factory Ohmage of the lighting coil.

The mounting holes had to be drilled out a little to make it fit on the stator - perhaps the gap is a bit too large at the moment.

When i say the multimeter was getting weird readings - it was sweeping between hundreds of volts AC to a handful and then back up again. I used a bridge rectifier to get DC and the same was happening. It was like it was getting interference. I tested my Yamaha DT175A coil the other week and it was reading fine at just around 7 volts at idle without a regulator so i know the meter works.

Proof is in the pudding i guess - glowing a 12V bulb at idle and a little brightness at half throttle.

[lukeb1961]

you say it is lighting a 12v 21w tail light.
The PE250/400 lighting in _total_ was only about 20w of 6v. The headlight was 15, the taillight was 5.
Brake and blinkers were drawn off the battery.
Lighting coil should be putting out 5.6v->8.5v@8000.

[Montynut]

Thanks for your reply, Montynut. We never had an original lighting coil to work off unfortunately. We used the iron from an old pulser coil and an old ignition coil and sandwiched them together. Perhaps there's not enough iron. or too much iron more likely

I'm just digging out the PE400T manual now to get the factory Ohmage of the lighting coil. this is affected by the cross sectional area of the wire not just the length. remember it is the number of turns not resistance

The mounting holes had to be drilled out a little to make it fit on the stator this could easily cause major overheating due to the iron circuit shorts - perhaps the gap is a bit too large at the moment.

When i say the multimeter was getting weird readings - it was sweeping between hundreds of volts AC to a handful and then back up again. I used a bridge rectifier to get DC and the same was happening. It was like it was getting interference. I tested my Yamaha DT175A coil the other week and it was reading fine at just around 7 volts at idle without a regulator so i know the meter works.

Proof is in the pudding i guess - glowing a 12V bulb at idle and a little brightness at half throttle.

[tdpomodoro]

you say it is lighting a 12v 21w tail light.
The PE250/400 lighting in _total_ was only about 20w of 6v. The headlight was 15, the taillight was 5.
Brake and blinkers were drawn off the battery.
Lighting coil should be putting out 5.6v->8.5v@8000.

lukeb1961,

I tracked down the owner's manual last night and yes was surprised to see the front headlight was only 15W. Thanks also for the output figures of the coil. Dad's going to track down a 6V bulb and give it a go.

Montynut,

That's interesting what you said about too much iron - i'll bear this in mind.

Regarding the drilling out of holes, also a good point that I didn't consider. The extent of modification to the holes was reaming them out about 1 - 2mm each to make them fit. I'll be sure to monitor that.

I'll report back once we have another crack. Meanwhile, i'll put a 6V regulator on order.

[Montynut]

If you fit a regulator (rectifier/regulator) you also need a largish capactor to act as a load to allow the regulator to operate otherwise it will almost certainly fail when the lights are turned off.

[tdpomodoro]

If you fit a regulator you also need a largish capactor to act as a load to allow the regulator to operate otherwise it will almost certainly fail when the lights are turned off.

Again, thanks for the info Montynut! Most helpful.

[tdpomodoro]

Bit of an update:

Tried alot of things to get this home-brewed coil to work to no avail.
Possibly the gap between the coil's core and the flywheel is too great. The way dad has the stator set up is using one mounting hole for say lighting coil "A" and one mounting hole for coil "B" - straddling across the stator.

The path forward I think:

1) Either get a PE250 T/X or PE400 T/X coil - I've checked part numbers and it looks like that the are interchangeable - can anyone confirm this?

2) Or get a TS185 coil which will fit will a little coercing from a file - Can anyone also confirm this for me?

3) I've also been told that the following can be used but will require a new stator plate. http://www.rickystator.com/catalog/suzuki-lt500r-watt-lighting-coils-p-243.html

I've also scratch built a voltage regulator that i've currently got running at 6V and is good for 8A. I can easily change a single resistor to get 12V @ 8A if needs be - depending on what I can get out of whatever coil i can source. If anyone would like any info on making their own DC linear voltage regulator i'll be happy to start a thread. Only a resistor change to get your desired output voltage. Cost of build < $15.

[TT5 Matt]

yeah put the circuit up fo the 6 and 12v,i like playing around with electronics

[tdpomodoro]

yeah put the circuit up fo the 6 and 12v,i like playing around with electronics

Started a thread as requested http://ozvmx.com/community/index.php?topic=25750.0