Switch motors and LED lights

What kind of switch machines are you using. I use Tortoise and DZ1000 switch machines and both allow for LED indicator lights on either the switch controller (DZ) or by using bi-color LEDS through a DPDT mini switch (Tortoise) Both work well but the Tortoise is by far the best switch machine made.

I just put a yard control panel together and used Atlas #200 Snap Relays to power LED's on the control panel...  The Atlas Snap relay is DPDT and it switches with the same AC momentary voltage that drives the switch machine...   I just powered the LED's with DC and an inline resistor.. If you want more info.  email me.    with this arrangement I have the LED indication for some older Atlas O Switch machines on my yard ladder tracks.   The Atlas SNAP DPDT relays stay in the position last set, so the panel indicator lights stay on all the time either RED or GREEN...

Assuming that the switch machine in question does not provide an output, the "simplest" solution would be to use a pair of relays set up to latch when one or the other button is pressed.  There are other methods that will do this just as well with solid state parts, and for about the same cost, but the relays are easy to understand.  

JGL

Here is a wiring diagram showing how I did it with the single Atlas Snap Relay, you can find these at train shows from time to time,  I bought 15 of them for $45.00.  It's very simple and easy to wire up, pretty old school but they work, and there's a second set of contacts on the relay to hook up a dwarf signal at the turnout if I decide to go that route.....  

Upper Rectangle is the Atlas Snap Relay,  apply appropriate DC voltage for the LED lights,

The Yellow and Dark Gray wire leads on the right are the switched AC Common leads coming from your momentary switch.    

 The Blue line is the AC Switch power 12 to 16 VAC depending  on which switch machine you are using. 

I'm going to paste your other post here.  Generally you'll want to keep a single subject in one thread and just reply there with the information, rather than starting a new thread.  

RRnewbie posted:

Thank you to those who have responded to my post earlier today! I have been asked to provide additional info for clarity so here goes: I'm running three rail AC. I have MTH Scaletrax track and switches. I have DCS with TIU and AIU. The switch machines are not powered by the track, they are powered through the AIU. Everything functions normally and as intended by MTH. I wish to install NJ International LED switch indicators along the mainline. These indicators have two separate LEDs, one red and one green. Each colored light has a resistor soldered to the power lead and an additional ground lead without a resistor. My desire is to have the green light remain on constantly when the switch is straight, and the red light remain on constantly when the switch is curved. The Scaletrax switch motor is powered only momentarily, then off after moving the rails to prevent coil burn out.

Wiring the lights to the switch motor unfortunately illuminates them only momentarily. If anyone knows of a simple remedy, and hopefully not too costly as I have 20 switches, I would be most appreciative. I am not an electrician, therefore "simple explanation" would be key. Thanks in advance for your help.

There was a post a while back about this same problem with these switches, which was the reason I made the schematic and video posted in my last reply.  Using relays as shown will get the job done, for the most part, however the signals will not necessarily show the correct lights until after the first time they are thrown.  

To use the latching relay method will require two SPDT relays for each switch (Edit:  you could also use a single latching relay, but the cost is about the same or higher going this route.) , with a cost of about $1.75 each form Digikey, or about 60 cents a piece on the auction site, shipped out of China.  Relative to the cost of many things in this hobby going the relay route may be cost effective; $25-70 for all 20 switches.  I can explain this method in more detail if needed.  

The second method I can think of is much more complex on the surface, but would get the job done with no mechanical parts and could be made, pretty easily, to remember which way switches are thrown when power is turned off and then on again later.  Here you could use a micro-controller, such as an Arduino, to read the signals from the switches being thrown, and to output the signals to the LEDs.  Doing this would probably require changing what value of resistor is used on the LEDs from the one that is provided, though it could also be accomplished in other ways.  The work is a bit more involved, but you could do it with a couple dollars of parts, plus an $8.00 Arduino Mega2560, or a $2.25 Arduino Nano and half a dozen or so additional IC chips totaling about $1.00.   The Microcontroller method is much lower cost in theory (As little as about $6 for all 20 switches), however it requires running wires from a central location to each of the LED signals.  The programing end of this would be a bit difficult for someone new to micro-controllers, but if this method seems like an option, my email is in my profile, and I'd be happy to write some code to get the job done for you.  

You could also get the task done with discrete logic gates, but this will get more complex than either of the other options.  If you want to see about this method, I'll have to do some homework, but it will be somewhere in the middle as far as cost, to my best guess.  

JGL