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Help wiring LED's. Hey fellow o scale model train enthusiast. I bought an old o scale kasiner vista dome car kit from about 1949 and they never included lights. I’m assembling the kit and going to make it look like my other cars by k-line. They sold these kits without truck and couplers. So I bought them 3 rail Lionel ones on eBay I want to wire it up with these leds DiCUNO 450pcs (5 Colors x 90pcs) 5mm LED Light Emitting Diode Round Assorted Color White/Red/Yellow/Green/Blue Kit Box to be honest I don’t know if I wire them to the third rail will it be too much voltage? Do I need a resistor and if so what one. My transformer that I use is MTH 750 but planning on upgrading to the z1000. I don't know if that information is important. Thanks in advance!

Here's a link to me making part for this kit.


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Last edited by Joey K
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You need a resistor and  you need DC not AC.   I think most 3 rail systems are AC but not sure.

I recommend starting with a 3000 OHM resistor (3k) and see how bright they are.   If too bright get highter - 10, if too dim go lower to 1.5k.     trial and error.  

For the DC, get a bridge rectifier.    Wire the leads from the track to the "AC" poles and wire the lead to LED to the + and - poles.    The long lead on the LED goes to the + pole on the bridge.   Trial and error here will hurt anything.    MAKE sure the resistor is next to the LED on either pole.

Radio shack used to sell all this stuff.    Now heed to find on line maybe - or All Electronhics

Many, many folks here, myself included, use LED strip lights, not individual LEDs, to light passenger cars.   For those running DCS/TMCC/Legacy with 18V in the track, 12V strips are preferred.  For conventional operators, 5V strips are preferred.

Here is an example of 12V, 5 meter strip of 300 LEDs for $2.54 w/ free shipping:

Simply cut-off the length needed for a particular car.

Power from the track runs through a regulator like @gunrunnerjohn provides via Hennings Trains (just click on the link in his signature above) or from a LM 2596 AC/DC buck converter available on eBay.

Good luck with your project, especially the brass vista dome fabrication.

Last edited by Pingman

No problem at all using LED's.  If you're using more than one LED, you can wire them to protect each other and just add a resistor to run them from track power.  You can also wire a bunch of LED's in series and only use one resistor for the lot.

How many LED's are you using?

OMG thanks so much for all the responses! I’m thinking about 2 on the long side 3 in the vista dome and 1 on the small side but not sure yet if I should add one more to each 4F6F6BC8-3B79-45F5-A6A6-6DB451A716E8


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Thanks! I took a look at those links and was wondering if I used 6 of those white LED's what resistor do you think I would need?

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