Connecting Foward And Rear Lights

[alloboard]

In a Digitrax decoder, how do you connect the foward (white FOF) and the rear (yellow FOR) light to the common (blue +common)? I need an illustration demonstrating this.

[tstage]

alloboard,

It depends whether you are powering incandescent bulbs or LEDs...

For incandescents bulbs it's fairly simple:

• Front headlight - The white wire is soldered to either one of the headlight wires (doesn't matter) and the blue (or common) wire is soldered to the other headlight wire.
• Rear headlight - Same as above - except use the yellow wire

For LEDs it's a bit different.  LEDs are diodes and current only travels through them in one direction ONLY.  Therefore, connecting the correct wire on the correct LED lead is essential to them working properly:

• Front headlight - The white wire is soldered to the Cathode (-) lead and the blue wire (common) is attached to the Anode (+) lead
• Rear headlight - Same as above - except solder the yellow wire to Cathode (-)

Lastly, if you will be operating both front and rear headlights, you'll obviously be sharing the common or blue wire.  What you'll need is an additional wire; preferably blue - but that's not essential.

All you need is to solder the additional wire to the common lead side of the front headlight and solder the other end to the common lead of the rear headlight.  You should be good to go then...

Tom

[alloboard]

I saw the diagram . It wasn't clear.

[Rangerover1944]

The Blue wire is the common ground and the yellow wire is for the rear light, the white wire is the front light. Jim

[JoeinPA]

Rangerover1944

The Blue wire is the common ground and the yellow wire is for the rear light, the white wire is the front light. Jim

Jim:

A little clarification. The blue wire is the common positive.  The yellow and white are negative sinks.

Joe

[Rangerover1944]

OOPS, my bad, typing too fast gets me in trouble especially 3:00 o'clock in the AM.

[Train Modeler]

There is a diagram on the packaging and it would help to answer if we knew what format you have.    BTW, the lights/colored wires are the same for all decoders, it's part of the standardization.    Blue is always the positive common.   But it's voltage value depends on what decoder you have.   And there may not actually be a wire for example with an AT format.    In this case you bring both positive wires from each bulb to the single pad(again if this is how it's configured).

Richard

[simon1966]

This is the question that has folks rolling their eyes and wondering if you are serious?  If you have ever hard wired a decoder, or ever read a decoder installation sheet from any DCC decoder maker then this should be basic knowledge.   Frankly I am not sure what you don't understand?   Here is one of the many reference sites, this one using LED's  http://www.tonystrains.com/technews/install-leds-decoders.htm

Since the decoder only has one blue wire you have to join the two blue leads from the LED.