Ignition Coils

The only data sheet I would expect to find is one that tells which engines this coil was designed to work with. Possibly you can get an exterior mechanical drawing. You are using this ignition coil in a completely different method than it was originally meant to be used. You should expect to get absolutely no help from BMW or any of their sub-assembly manufacturers. The design of their parts is proprietary information. If you cannot reverse engineer the part you have in hand to see if it suitable for your needs then they will probably not help you.

The only method you might be able to get some design help from BMW is if you were designing something completely outside of the automotive field that they'd be proud to say that their parts were used. Mammal electrocution likely will not be something they'd be proud of. If you succeeded in getting their help it would like come with a non-disclosure agreement. BMW must protect themselves and their suppliers.

I have begun testing with a coil scrounged from the mechanic whom carried out the annual safety check on my diesel car. It is not a branded main dealer and they sometimes buy damaged cars and break them for spares. It looks well on the way to my veg plot by the end of the week. Have a look at my post about 3842 odd jobs for a description of the driver circuit and the old unit built 10 years ago.

I am using it to "drive off" unwanted mammals and not to kill them!

A commercial cattle fence driver costs about 4 times what i could sell these devices for on ebay and is far to powerful for my job.

I tried a spark coil to power a "deterrent" electric fence years ago and abandoned the idea after almost killing my own cat and a goat... Modern electric fence chargers pulse in order to allow the critter to get away and not be held by the continual shock... I think selling your device on E-Bay may lead to litigation...

The trick it to pulse it. This allows for there to be a high resistance between the power supply and the unit itself. The unit i am testing charges two capacitors. One supplies the pulse generator and the other the coil voltage. As soon as one of these is discharged the output stops. Then they have to charge up again. The resistor is selected to allow time for whatever you want to drive off to make its departure (about two seconds). The old one used a resistor on the low voltage terminal that just "slowed" the charge rate of the capacitor and that was it.

Why not just buy an electric fence charger. They have the build in safety needed. They are available powered by battery or mains voltage.

They are about four times the price and are made for use controlling much larger animals than i intend it to be used with. It is to drive relatively small animals off a vegetable plot. The old one has worked for a long time. I am trying to reproduce it ising current production parts.

I remember my uncle Don telling me about an electric fence he made with a flyback transformer off an old TV set. Never really thought about it since. Well, until I read this post. Oh well. Just an idea.

The advantage is that the car coil is sealed for use in a much more hostile environment that a TV part. The TV transformer is better for a plasma generator as per an experiment i did in the 1970s.

I can just see the Patent application:

Abstract:

A rodent repellent system is an extrordinary kluge of a computer with USB port, old stereo system, discarded car parts to accomplish the same end as some foul smelling preparation...

All with 45 YEARS of developement?

Please... go shoot the poor critters.

The idea is to program them into thinking they are being shot at with an air rifle.

It is like "hacking" there minds whilst those whom wish to keep them don't get upset or end up with a vet bill.

My onion sets have stayed in the ground!!!