Ignition system
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jimmy101
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I don't think you want to use a snubber diode in an HV ignition circuit, indeed I think it'll make the circuit not work.dewey-1 wrote:The diode suppresses the inductive back emf which can be a higher voltage than the switches can handle. Think of a higher voltage arc.
See this explanation:
http://en.wikipedia.org/wiki/File:FlybackExample.GIF
You want the field energy to collapse into the coil's secondary winding and not be snubbed (dumped, absorbed, wasted) by the diode across the primary winding. That is why car ignition circuits use a capacitor (condenser) and not a diode. The cap sources enough current to keep the voltage across the switch (car's ignition points) from exceeding the break down voltage.
edit: engrish
jimmy101;
I never stated to use on an ignition coil.
It was in reference to the relay coil.
I never stated to use on an ignition coil.
It was in reference to the relay coil.
Hey again! I have tried with other metods to fire up my ignition coil but with no success. I belive that its maybe broken or something... I have read that you van measure the ohm betwen - and +, and also - + and the middle. I would appreciate if someone could measure the ohm values on their coil and post them here! 
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jimmy101
- Sergeant Major 2
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Sorry, but you didn't actually specify which coil you meant. Since the OP is about an ignition coil and a simple switch that is what I assumed you were talking about.dewey-1 wrote:jimmy101;
I never stated to use on an ignition coil.
It was in reference to the relay coil.
For a buzz coil circuit a cap or diode across the relay's coil isn't needed. A cap across the HV coil's primary is needed and a diode in the same place will make the circuit not work.