[AT] Project Updates '49 A, '51 A, and '47 B (STEVE ALLEN)

[Stephen Offiler]

It's not about the points.  A voltage far in excess of battery voltage is
induced across the points by the coil primary as they open.  The ballast
resistor limits current in the coil to prevent overheating.

SO

On Mon, May 11, 2020 at 2:16 PM Kurt Musgrave <rvar at plainstel.com> wrote:

>
>
> >>You are correct Carl.  A 12V system takes a 12V coil with an internal
> resistor or and external 1.4 ohm resistor commonly called a ballast
> resistor can be used with a 6V coil.    These are available at most auto
> parts stores.   This is to avoid burning the points as you say.<<
>
>
>
> I never really understood why the ballast resistor, always seemed to me it
> would have been just as easy and probably cheaper to have just made points
> capable of handling the 12 volts, instead of the ballast resistor and the
> associated hassles.
>
>
>
>
>
>
>
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