Wendell Voto wrote:

I got the resistors from Mouser. They are on the internet. Mouser.com
Part # 284-HS25-.33    (.33ohm 25 Watt)
       # 284-HS25-5        (5 ohm 25 Watt)
Wendell

That brings up a good point.
Tracy what can we do to eliminate this waste of alternator power?
Also at issue; how can we extend the range of the aircraft
on battery power alone after the alternator fails?

Paul Lamar

Not really enough power to worry about.   Main time the ballast resistor
comes into play is during startup when the ECU doesn't have enough info to
accurately control the dwell (coil goes into saturation and current
sky-rockets).  Under normal running conditions the current is limited by
coil inductance and does not saturate. Stock  resistor does get a bit hot at
rpms above 4500 due to marginal rating, no airflow around it and location
(under the cowl).  It might be possible to reduce dissipation by 3-4 watts
by bypassing it after startup but that's probably more trouble than its
worth.

Tracy Crook
tcrook@rotaryaviation.com
www.rotaryaviation.com

Question Tracy. Is the Chev GM coil per plug a simple pulse
transformer or is the saturation current type?

Paul Lamar
 
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