Generator light

Bill McC,

You might have that backwards.

The "L" terminal on the Regulator is connected to the Field winding of the Alternator.

Notice that the Lamp is connected between the "C" (12v) Terminal and the "L" (Lamp) terminal.

The C terminal is Always 12v. So the Lamp is ON when the L terminal goes LOW (0v).

When the Lamp is OFF, The Field Windings are operating and the L terminal is very Near 12v.

The lamp is OFF because there is 12v on BOTH sides and so No Voltage Differtial and NO Current.

To operte a HOBBS off of the L terminal, the LOW side of the Hobbs would connect to Battery Ground and the HIGH Side would connect to the L terminal which is at 12v when the system is charging and the Lamp is OFF.

You have the correct idea, just the reverse polarities.

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Do you really need an ALT Warning Lamp???

The regulator came from the Automotive world where Battery Voltmeters and Ammeters are luxury items.

The ALT Warning Lamp is an inexpensive way to tell the operator that the Battery is not being charged.

In an Aircraft, Volt and Amp Meters are very common.

If the battery voltage is Above 13v, the battery is being charged.  What more is the Lamp going to tell you???

Bill Hertzel, you are correct. I should have pulled up the schematic... not relied on memory. Hobbs has one lead to ground , the other to  L terminal. I'm attaching the schematic. So with the light off, +12 comes though, and runs the hobbs.  a burned out light would stop hobbs.

I could be wrong, but i am not so sure about that.

The L terminal should be able to source the 12v all by itself without the Lamp present to pull it up.

Try removing the bulb and see if the Hobbs keeps on ticking.