difficulty wiring vol regulator

[dlotz]

ok
So I am following this diagram from ERA:
http://www.erareplicas.com/427man/wiring/alt.htm

With the warning light I have a question. It says from IGN switch (I assume this is a positive feed from the IGN, The other end would normally go to a ground for the light to work, but it say to send it to the "I" on the volt regulator with a 15ohm shunt (resistor) in between.

So is that lead to the "I" on the volt regulator a negative or Positive run?

I would think positive because of the shunt, but then how does the light get grounded to turn on?

Thanks

[Rick Parker]

Anything coming out of the ignition switch will be (+) Positive. The wire leg from the bulb to the Voltage Regulator attaches to a spade terminal that is internally grounded within the Voltage regulator, it remains lit during low or non charging conditions. When the Alternator begins to develop enough output, it energizes a field coil in the Voltage Regulator that breaks the set of contacts creating the ground circuit and the light goes out.

[dlotz]

Thanks Rick

That helps explain it.

[Excaliber]

That light burned out on me once and the alternator quit charging! My conclusion was that the IGN wire, through the light, is what "turns on" the voltage regulator. If the V.R. doesn't get turned on, the alternator never get's excited and the battery goes flat.

...why does this sound like some kind of "bedroom game"?