RE: Ignition Coil Experience

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Mike Veldman by way of Terry Fritz <twftesla-at-qwest-dot-net>" <vmike-at-email.ceat.okstate.edu>

I've done some work with automotive ignition coils, for their origional
intended purpose and some others.  The numbers I'll use here are close
approximates since it's been awhile.  In normal applications the coils
primary current is in the 3 to 4 amp range at 6 to 9 volts, the secondary
current under those conditions is divided by about a thousand.

A capacitor used in a series AC circuit will limit the current to approx.
20ma/MFD.  So, a 5uf is about 100ma to the coil primary and about a
microamp out of the secondary.

I've used automotive coils in a number of applications for which they were
not designed, successfully, but always at low current.  I do, however have
one that will put out a measured 35ma secondary current at 20kv.  It
consists of a 600 watt dimmer driving a bank of 660vac oil filled run
capacitors (forgotten the total mfd) into a GM HEI coil suspended in a
gallon of transformer oil (gallon paint can), used to flare off hard to
ignite gasses from a grass gassifier project.  I was using ignition
transformers, but their survivability rate was poor, this one has never
failed.

For a tesla supply however, a NST is a lot easier.
mike
"I tried to contain myself, but I escaped"