Incandescent Light Bulb Replacement

@gunrunnerjohn posted:

The kits come with two sets, but if you don't mind a little soldering, I could probably arrange to get you one regulator board as a strip of LED's.

Thanks for the reply John!   I bought one of your kits last summer and used it to light my W24 and coach 33 project.   The Northland car came with incandescent lighting.   I am thinking of upgrading the lighting to LED.   I also have all the parts (Digi-Key) needed to regulate the power for a Mars Light Simulator - N8031C.   Would the regulator for the LED strip also supply proper power for the simulator board?   If the answer is yes, it would simplify the MLS instillation.   I do not mind soldering but may need some direction for the connections.  

The current lighting board also powers the marker lights and tail end light which are both LEDs.  I assume that the regulator would also work for them.    

Again Thanks for the help!

Cheers, Dave

GRJ will respond but out of curiosity did you remove the brown circuit board with the bulbs? It looks like there are 3 pairs of wires, 2 for the markers and 1 for rear light. Where do these LED wires go?  I'm guessing there are some components or maybe even a small circuit board to handle just the LEDs - especially since each marker appears to be 2 LEDS of different color.

When I do these, I removed the board in total.  I just string the two or three LED's for the markers/taillight in series and use a balancing resistor to adjust the brightness of those as compared to the strip lights.

Stan, I believe the markers have a single LED, the lenses on the markers create the different colors.

@stan2004 posted:

GRJ will respond but out of curiosity did you remove the brown circuit board with the bulbs? It looks like there are 3 pairs of wires, 2 for the markers and 1 for rear light. Where do these LED wires go?  I'm guessing there are some components or maybe even a small circuit board to handle just the LEDs - especially since each marker appears to be 2 LEDS of different color.

When I do the LED upgrade, I will remove the brown board and tape the LED strip to the cars ceiling.     The marker lights are part of the original circuit so yes, there is a small circuit for the LED lights.   I added the rear tail light and connected it to the same marker light circuit.   I want to know if the regulator that comes with the LED kit will also supply the correct power to the N8031C Mars Light Simulator and the current LED marker lights.    John advised me earlier as to what I needed in order to operate the MLS with the old lighting system (brown board).   I have the parts to build the circuit he suggested but, If the regulator that comes with the lighting kit will supply the proper power, I can save time and space by using the kits regulator for the MLS.    That's my dilemma.  

Cheers, Dave

@gunrunnerjohn posted:

When I do these, I removed the board in total.  I just string the two or three LED's for the markers/taillight in series and use a balancing resistor to adjust the brightness of those as compared to the strip lights.

Stan, I believe the markers have a single LED, the lenses on the markers create the different colors.

Thanks John!  I will remove the board.   The marker lights have a single LED.   The taillight is connected to that same circuit.   I am hoping to use the Light kit LED circuit for the marker lights, taillight and mars simulator.   Look forward to any other suggestions regarding this project.  

Cheers, Dave

From the Ngineering site:

If the N8031/A/C is to be used in a stationary (not track powered) application, it can also be powered by any well-filtered and regulated DC power source with an output of 6-18VDC.

What is this circuit that GRJ provided to drive the 8031C?  If you're going to use his LED board, and you're somewhat handy with a soldering iron, you should be able to tap into his LED board to materially reduce the extra components.  That is, I believe you can re-use the bridge rectifier, capacitor, and DCS inductor (if applicable).  The Ngineering requirements are somewhat confusing as I think it odd to say a regulated DC with such a wide range.  In any case you do need to knock down the DC voltage as 18V AC track voltage will exceed 18V DC.

I'd say not to use the lighting regulator for the MARS simulator.  Since the LED lighting board is a constant current board, it's voltage varies dependent on the load.  Given that fact, I'd want to use a true constant voltage board for the MARS simulator.  I have used this board for the MARS simulator in a number of installs.  You can use an LM78Lxx regulator, a good choice is the LM70L08 for 8 volts out.  Enough for the MARS simulator board, but not enough voltage to overwhelm it.

Here's the connection diagram.

Here's the BOM for the parts.

Note that C1 is optional, I stick them in as it helps with stability of the regulator if the load is distant from the board.  The 22uh choke is for DCS compatibility, if you really don't want to include it, just jumper that position.  So, you can really build this with just three parts if you want to go "bare bones".

Here's the schematic for this board.

Here's the Gerber files if you want to make a few and keep them around for similar projects.  Just drop this at OSHPark and they'll whack you out three boards for $1.40.

LM78Lxx Power Module Gerber.zip

@stan2004 posted:

The Ngineering requirements are somewhat confusing as I think it odd to say a regulated DC with such a wide range.  In any case you do need to knock down the DC voltage as 18V AC track voltage will exceed 18V DC.

There is a tiny regulator on the Ngineering MARS board, but it doesn't have any filter caps, so that's why they're saying "regulated".  I really think they mean smoothed DC, but that's my interpretation.  I also don't recommend my constant current board as the adjustment could easily force the voltage to exceed 18 volts if the MARS board isn't drawing enough current.

@gunrunnerjohn posted:

Here's the connection diagram.

Thanks Stan & John for your help and suggestions.   John specials thanks for the schematic and parts list.     I will be messaging you sometime this week regarding an LED light strip and regulator.  

Cheers, Dave