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I am planning on upgrading my Lionel Bipolar (product #6-18384) to have LED lighting, but I have run into a few issues with the current plan. If anyone has done this kind of modification, be sure to share any tips in this thread.

First, the original headlights appear to be working as intended. But when I try to get a voltage reading from the headlight output, I get 0.5 volts in DC mode and 0 volts in AC mode on my multi-meter. That voltage does go down to 0 when I change directions. The marker lights are wired to track power and I can indeed see 17 Volts AC (which is the maximum my transformer puts out). So why is it that I can't see the output voltage for the headlight?

Also, I plan on putting in LED bi-color classification lights in as well. So I assume that I would need to tap into one of the board that has marker light outputs. The DCDS-J Motor driver board (691DCDS105) does appear to have at least 1 marker light output, but I can't seem to find a second one at the moment. But I will check later.

Any tips and help are appreciated!

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In order to use strictly LED lighting on the R2LC, you need to add .01uf capacitors across the lighting outputs to ground to trigger the lighting triacs.  If you plan on using the smoke output for lighting as well, add the cap to it too.

The DCDS boards had a variety of lighting outputs, it depended on the specific locomotive, the outputs were programmed for the job.

If you program the R2LC for a cab light, the smoke output is the cab light.  It will change polarity based on direction, this allows you to use bi-color LED's and drive them from that output.

The interior lights may be programmed to turn off when you start moving, depending on the version of R4LC it has.  If so, they may not be suitable for classification lights.  The smoke is controlled by the smoke regulator, it doesn't use the smoke output.

Here's a diagram for LED headlights and directional markers.  This just uses the R2LC/R4LC headlight outputs to control all the lighting.  Note that the dual headlights are optional, you can use just one LED as well.  The bi-color LED's are common anode 3-wire type.

The diode at the bottom is to protect everything from reverse voltage, and the .01 caps are the triac loads.  The resistor values were picked for the red/green LED's I used, you can vary them to affect brightness.  I like the markers to be clearly visible, but not competing with the headlights, so you might choose to adjust those values.

Directional Locomotive LED Markers & Headlights


Images (1)
  • Directional Locomotive LED Markers & Headlights
Last edited by gunrunnerjohn

They actually are just manual interior lights, they are either on or off and controlled with the smoke unit buttons.

I am thinking more of a wiring setup like this:Lionel Bipolar LED wiring schamatic

The setup for the headlight will be for each A end of the engine, and the cab lights would be directional with the headlight. The marker lights will be connected to the original interior light bulb wires/connections and the original incandescent light bulb in the middle section will remain, so that should allow the triacs to activate for the smoke unit output. All the resistors will be 0.5 watts, so they will be a bit cooler.


Images (1)
  • Lionel Bipolar LED wiring schamatic
Last edited by MichaelB
gunrunnerjohn posted:

Without a polarity reversal, I don't see how the bi-directional markers change colors...

Clearly, I don't really understand what you're trying to accomplish here.  Without a complete diagram of how you're wiring this, it's hard to see what it accomplishes.

Yeah sorry I am not super good with those. I checked the voltage on the interior lights and they do change polarity (go from 7 Volts to -7 Volts when I change direction). So my idea for the marker lights will work if I connect them to the wires that the interior lights originally connected to (which is the smoke unit part of the board). And because I found out that it actually has 7 volts to the interior lights, I won't need as large of a resistance for the class light circuit and will only need a 0.25 watt resistor.

I will later change this thread to have a different title name and have pictures updating the status of the project.

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