LED wiring for manual throw turnouts

[Palmland]

My question is related to the thread on LED wiring with Tortoise. While I do use tortoise for most of my mainline turnouts, in the yard I ofen use a manual throw with Peco turnouts for my DCC layout. To get correct polarity in the frog I use a switch wired from the track power through the micro switch then to the frog. So far so good. But then basic electronics escape me (my least favorite part of the hobby).

How can I wire a bi-color LED on my panel to these electrical switches for my manual turnouts.

Wiring them in series as I do with the Tortoise doesn't work presumably because they aren't drawing current. My control panel uses 12V DC power for the powered turnouts along with DPDT then to the tortoise.. I'm sure there is a way for the manual switches, but I must be brain dead.

Appreciate any help.

[NeO6874]

if I am understanding your post correctly, your manual throw TOs are wired with a DPDT switch that reverses polarity feeding the frog.... you could wire the LED in a series (between the switch and the frog) so that it shows the color you want based on the orientation for the frog.

wire it like this:

DPDT Switch ------ LED----frog

though you could always wire it parallel as well (though that would be a little more tricky, and i don't exactly know how to do it...)

[claycts]

YOU MUST HAVE A RESISTOR in the circut or POP goes the LED. The Tortise is the resistor.

Alternate plan "B" is GRAIN OF RICE bulbs from Micro Mark. They take full line voltage and work very well. They like a resistor also but work well without one.

[MisterBeasley]

I haven't tried this, but it should work:

Use a bi-color LED.  These have 3 leads, common, red and green.  (They do make them in other colors, but those are the most common for MR use.)  Connect the common lead to a 1K resistor, and then connect the resistor to the frog.  Connect the red lead to one outside rail of the turnout, and the green lead to the other outside rail.  When the turnout is thrown in the "straight" position, the frog power will be the same as the "curved" outside rail, so current will flow through one side of the LED.  When you throw the turnout to the "curved" position, the frog polarity will flip and current will flow through the other side of the LED.

This works in DCC because the voltage on the track is a modulated square wave, which looks kind of like AC to the LED.  The diode character of the LED acts like a half-wave rectifier, but it's fast enough that the LED will actually turn on and off much more rapidly than your eye can see.

[Palmland]

Mister Beasley

Thanks for your comments. It sounds like it might work. My post may have been confusing, but as you surmised, there are no DPDT involved with my manual turnouts. Simply a piano wire through the points, to a rode that moves when the points are thrown. The rode trigers the micro switch to on or off for the frog polarity.

I did use a 470 ohm resistor hooked in series and it worked some of the time. Your post indicates my problem. The LED only has 2 leads, not 3. So I will give your solution a try.

Unfortunately all my LED's are two wire leads. Where can I get a 3 lead bi-color. I like my particular brand (Lumex purchased through Allied Electronics) because it is designed to just insert into the hole in the control panel and stays in place through pressure - no nuts required to secure and looks  good.

[donhalshanks]

Am working on similar thing, and just received from Walthers (Caboose Industries #220S) ground throws (pretty cheap) that have a SPST switch built into it, which does its thing with the frog when throwing it. Saves having to use a micro switch. Has connectors extending below the throw to connect wires to the turnout.

Also got a dwarf signal with red and green LED's. Instructions say to use 1/2w resistors in -line with the red and green for 12.5 DC power.
--Hal

[hucomp]

This is very helpful as I am trying to do exactly this! But the instruction are for electrofrog turnouts. To do the same for insulfrog turnouts you need to attach wires to both point rails then join them together with the common wire on the LED (3 wires now running to the resistor and the common LED wire) and you're in business. You will have to test the light to see which wire goes where but it does work! This can also be done with installed turnouts by running the necessary wires up through the baseboard and soldering them to the specific rails (this is what I had to do.)

Cheers

[Scotty]

[quote user="hucomp"]

This is very helpful as I am trying to do exactly this! But the instruction are for electrofrog turnouts. To do the same for insulfrog turnouts you need to attach wires to both point rails then join them together with the common wire on the LED (3 wires now running to the resistor and the common LED wire) and you're in business. You will have to test the light to see which wire goes where but it does work! This can also be done with installed turnouts by running the necessary wires up through the baseboard and soldering them to the specific rails (this is what I had to do.)

Cheers

 Hi. I'm very new to DCC and I am trying to put an LED to a manual throw, but my turnout is an Insulfrog. I couldn't follow your suggestion and wondered if you could elaborate as to wiring the LED from the point rails?

 

[John Busby]

Hi palmland

Start by geting the right caboose industries ground throw with the right contacts, that is also your electrical switch. 

Get a bulk bag of yellow LED's it will be cheaper than Bi or Tri colour LED's

On your panel lay out to represent the switch yellow LED's in a triangle, one for main line one for siding one where the toe of the blades is.

Wire the blade toe LED so it is perminatly lit wire the other two so when the ground throw is throw the LED for that track lights up and the other track one goes out. you have a clear unmistakeable Two LED indication of which track the switch is set for.

Wired correctly the LED triangle will show the direction points are set and that the polarity has changed to suit idealy you want both to change at the same time.

Do not forget the resistors or the LED'S will blow.

Hopefully some one a bit more knowledgable can draw an easy to follow diagram from my description.

regards John