Engine headlight

[jarveym]

I am new to dcc and my first decoder installation will be in a IHC 4-8-2. My question is will I need to change the bulb to a different voltage, please help, thanks is advance.

[cacole]

No, leave the headlight alone. On IHC models, the headlight is wired to electrical contacts at the front of the locomotive and will just remain on all the time instead of being DCC controllable. IHC uses a 16 Volt bulb, so it will not need to be changed.

Now, if you really want to control the headlight from the decoder, you can replace the bulb with one that has longer wires, or add longer wires to the existing bulb so it can be connected to the decoder's output through a small current-limiting resistor of around 22 Ohms. This resistor is necessary to protect the decoder from the sudden current surge when the bulb is turned on.

Routing the new wiring around the weight that is inside the boiler is a major project, however, so I just leave the original bulbs wired as they are.