LED Lighting installation help

I'm not sure of exactly what you're asking, but I suggest you look at Evans Designs.  They have a tremendous selection of LEDs that work very well in our hobby.

@texgeekboy posted:

I'm not sure of exactly what you're asking, but I suggest you look at Evans Designs.  They have a tremendous selection of LEDs that work very well in our hobby.

I agree.  They have lots of stuff for both beginners and those with experience plus they are very helpful.  Highly recommended.

John

@Bossman284 posted:

Ok I'm not really experienced with LED and I'm looking for some help.  I basically have two 5mm LED lights that are mounted in a structure. I want to wire them in such a way that they can be activated by a push butten near the edge of the layout when people walk by (sort of an interactive experience)  I also want them to be independently powered from the layout, via either battery or walwart  (battery is prefered) ad the unit may also move off the layout for other uses.  Can someone tell me how to accomplish this and where I might get the components for this project.   Thanks in advance

First, what voltage do you need for the LEDs? If they were pre-wired into the structure, the spec's would likely be in the manual or setup directions. Most 'bare' LEDs run on something close to 3 volts, but many, especially those intended to be powered from model railroading accessory power sources, come with wired-in or add-on resistors that allow higher supply voltages to be used.

If the LEDs need just 3 volts, you might be able to find a two-cell (AA or AAA) battery pack, and all you'd then need to do is wire a single-pole momentary contact switch in series on one lead from the battery pack to the LEDs (note: you will need to be sure the battery and LED polarities match, since the LEDs will not light if polarity is reversed)). Or, you could set up an inexpensive buck converter, which can take any available voltage, 5-30 volts and either AC or DC, and convert it to a regulated and adjustable DC output. If you do use a buck converter, you can insert the push button switch into one of either the input or output wires (I'd be inclined to go with the input, since otherwise the buck converter will be "on" constantly).

If the LEDs are already pre-wired for accessory-level power (12-20 volts), you'll need an appropriate power source (wall wart or accessory tap on the transformer), and the switch should be inserted in series in one of the wires to the LEDs. Again, a buck converter can allow you to adjust and regulate the voltage from any available power source (IMHO batteries would not be suitable for higher voltages).

For the sake of an easy installation process, because wiring under the table has become a challenge for me, I started to use the "Woodland Scenics Just-Plug" lighting system.  The cost can add up quick, but the ease of installation is the best. The power supply is not connected in any way to the transformer, but straight to a dedicated wall outlet.  Woodland has a nice selection of leds and nano leds...blinkly nano leds are available too.  The whole system is simply a plug into a port platform.  The lights can be turned on and off indivisually and the brightness can be adjusted.  I'm not aware of any way to turn them into a motion on situation though...

There are 3 approaches to lighting LEDs in buildings:

1. Buy the Woodland Scenics Just Plug system
This is the most expensive option, but it is a no brainer.  They sell LEDs, power supplies, battery packs, dimmer controls and even a control button you can mount.  You only need to "Just Plug."  Their system covers all lighting needs except the trains:  Buildings, Streetlights, Vehicles, etc.

2.   Buy pre-wired LEDs from Evans Designs
These are intermediate in cost.  They sell LEDs wired for 3V or 5-12V battery supplies, and 7-19V AC or DC.  They have power supplies, battery packs, switches, dimmers, timers, remote controls and more.  It is not plug and play but they have good instructions.

3.  Wire your own circuit.  This is by far the lowest cost option.  You will need to use an appropriately sized current limiting resistor.  Without this, depending on your power supply, your LEDs will flash brightly once and never light again, or will have a much shorter life.  This easy to use LED calculator will figure out what size resistor you need and will draw your circuit for you.  You will have some inconvenience in gathering up all your components (LEDs, Resistors, Battery pack or power supply, pushbutton).   You can get all of these on Amazon, eBay, or various electrical suppliers (Jameco, Digikey).  Expect the shipping cost will be more than the components.

Note that in the first 2 options you will replace the existing LEDs.  With option 3 you will need to know if the 2 LEDs are wired in parallel or series, as that greatly changes the circuit.

Bob