<VV> archer kit CDI?

[Tony Underwood]

At 12:16 PM 10/3/2009, Jay Pitchford wrote:
>Found via Google:
>
>" CDI is short for capacitive discharge ignition. It was an early form of
>electronic ignition, could use any type of trigger (points, optical,
>magnetic, or?) The premise was that the CDI would save up a bunch of energy
>during the time the points were closed, then release a VERY short burst of
>mega-kilo-ton energy to the coil when the points opened. This produced a
>very short duration spark capable of very high voltage (any ignition system
>will only develop the voltage required to spark, not the maximim it's
>capable of) They were especially useful in firing plugs that had a tendency
>to foul like 2 strokes or old engines with oil control problems. The short
>spark duration in general did not cause coil overheating due to it's short
>duration. '



The CDI ignition did this by charging a capacitor to a higher voltage 
than a stock coil would ever see, which generated a higher intensity 
spark than 12 volts could ever generate and it does it without 
loading the points.

Handy.   :)

Later variants eliminated points altogether although the points type 
are still quite capable since dwell is almost a nonconsideration and 
the current flow through the points is so low it's almost a 
nonentity.  They are however technically complicated and they do work 
the coil pretty hard, in that they generate a very high 2nd anode 
voltage which can arc through less capable coils internally.   Use a 
premium grade coil.  ;)



tony..