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Discussion Starter #1
So some may recall these recent post about LED's and turnouts. I decided to make it its own thred as it stared as a simple question under MDE's thread about servo switching and figured it was time to get his back under his topic.

For those that are unfamilar, I want to mount LED's above the switch (the actual controle that activated the solenoid and its made by atlas) to indicate on my controle pannel which direction the turnout is thrown.

I am aware of the tortis motors but I cannot justify forking out x for each motor. I have 14 turnouts and that will add up quickly. I looking for a way I can hook up the LED's directly to the switch. I think it was DonR mentioned momantary DPDT's, but the LED would only be light up for a second or or how long you held it.

My question is can I use a DPDT and above it place an open momantary above it and above the momentary have my LED?




Next Question is if the above is possiable how to hook up/ wire a dual G and R LED to cut down on space and wiring?
 

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As far as I understand it your switch motors are solenoids which are triggered by a momentary pulse of power from the control switch, i.e. you are not using a continuous power supply and therefore this is inconsistent with the requirement for powering the led indicators on the mimic. If you use two switches one for the points and one for the LEDs you have the problem that there is no guarantee the LED indication will be the same as the point position. The only way I can see for the momentary point control switch to also change the LED indication is to use what is known as a flip flop circuit. In this circuit the circuit changes state from on to off each time it gets a pulse e.g. from the point switch. This on off can then drive a simple two pole relay to change the LED indication. This is a fairly simple circuit but again there is no way to guarantee the LED and points remain synchronised, and you would need one of these circuits for each point.
The only way I can see of guaranteeing the LED indicators mimic the points is to drive them by a sensor on the points, this is much more complicated and also requires a lot of additional wiring.
This complication is the reason I went for the servo point motors as I bought 12 servos for $61USD and the micro processor controller and mimic driver was an additional 120 Pounds Sterling. The up front cost was a bit higher but if you look at the overall cost of all the extra complication for the other systems it is cheaper in the long run.

Regards MDE
 

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LED indicators

SBRacing;
I think I understand what you want, but I'm not sure. Are you using the old Atlas controls. I remember them having a square, blue plastic button. One slid this button right or left within it's
rectangular black plastic housing and then pushed it down for a second to throw the turnout.
Is that the type of control you are using? It was sort of a combined SPDT slide switch and a momentary push button, in one unit.
If that's what you have there will be serious challenges in hooking LEDs to it. You can't simply wire the two together as the LEDs run on low current DC, and the solenoid switch machine you are controlling uses a short burst of very high current AC. LEDs hate high current. It burns them out instantly. Therefore, we need some mechanical, not electrical, means of connecting the LEDs to the controller. Using that Atlas controller, Good Luck! The best I can think of would be to mount a slide switch on it's side atop the control panel and physically connect it's sliding
"button/handle" to the blue one on the Atlas controller. Tricky, ugly, and in the end, it won't really tell you which position the turnout is in. If you slid it to the left, that LED would light, but unless you push that blue button down, the turnout would not have changed to the position now indicated.

If, on the other hand you are using say a DPDT toggle switch, and a separate, momentary push button; it becomes simpler to do what you want. It will still not necessarily indicate true turnout position though, so I don't see the benefit.
Please send a photo of the control/s you are using. That would help me understand what you're dealing with.

Traction Fan
 

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SB,
You could make a simple contact switch at the turnout by using the throw bar of the turnout as one contact point (+ in) then inlay two more contacts below the throw bar (+ out) with this configuration the led's will always be lit red or green! I realize that would require a lot of additional wiring etc. Just my two cents!
 

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SB,
You could make a simple contact switch at the turnout by using the throw bar of the turnout as one contact point (+ in) then inlay two more contacts below the throw bar (+ out) with this configuration the led's will always be lit red or green! I realize that would require a lot of additional wiring etc. Just my two cents!
Gator has a very nice suggestion here.

It would be an inexpensive way to get the turnout point indication that
you want without buying switches or relays.

You could use a transistorized circuit but one would be required for
each turnout.

If you don't use Gator's suggestion, the most inexpensive solution
is to use the DPDT switch as I had earlier indicated. One side switches
the point thru a momentary push button. The other side switches the
LED from Red to Green. I agree, it is NOT a POSITIVE indication of
point direction, because you must push the button after throwing
the DPDT. If you don't, your LED will give a false indication.

NOTE: The DPDT is NOT momentary.

Don
 

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Discussion Starter #6
Here is the atlas.
Switch.png

Ill more than likely uses a DPDT and I will have to add in a momentay switch to not burn up the motor
 

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Use a normally open momentary push button connected before
the middle tab on the DPDT turnout motor side. To throw the
turnout, throw the switch to straight or divert, then push the
button. The LEDs are connected to the end tabs on the other
half of the DPDT switch and do NOT use a push button.

Don
 

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Discussion Starter #8 (Edited)
A bit confused DonR, when you said DONT use a momentry you are talking about the LED side, correct.

My next question is where on the DPDT should the power be entering in at?

DPDT.png
 

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Your drawing is absolutely correct.

The power for turnout motors and
LEDs attaches to the MIDDLE tabs exactly as
you have on your drawing.

Yes, the momentary button goes, only
as you show in your drawing, on the side
to the turnout machines. The DPDT switch
is not momentary and does NOT have
an OFF in the middle position.

While you can use either a/c or d/c on your
turnout motors, you'll want only DC for
the LEDs. What do you have to power your
LED circuit?

Don
 

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Indicators

SBracing;

Thanks for the photo of your "Atlas switch controller". It looks like a more modern version of the one I remember, and should work the same way. I understood your question to be asking for some method of activating LEDs from the control panel end of the circuit. Not knowing how much you know about model railroad wiring,
I was reluctant to suggest controlling the LEDs from the turnout end.
If you are willing and able to do the wiring , I agree with the prior suggestions to rig up contacts at the turnout.
This will tell you which route the turnout is set for, which, I think, is what you wanted to accomplish.
The simplest power source for DC to the LEDs would be one of those "wall wart", plug in little black box chargers used for cell phones and such. You can get them, in a variety of voltage outputs, from allelectronics.com. I'd use a 3-5 volt type with a 68 ohm resistor in series. The resistor limits the current through the LEDs, and keeps them from burning out.

Good luck with your project!

Traction Fan
 

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Discussion Starter #12
So both turnout and LED will have seprate power supplies correct?

Would I be able to run a parrall series (bus) for my LEDs?
 

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Discussion Starter #13
And yes I know by looking at the LEDs will not be fool proof but the atlas switch one can slide back and forth all day and it be on the wrong side and that it is miss leading... so i used to having to make sure they are pushed after eveytime.
 

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So both turnout and LED will have seprate power supplies correct?

Would I be able to run a parrall series (bus) for my LEDs?
Yes, in most cases the turnouts and the LEDs should have
separate power sources.

If you have an old DC power pack, you could use the ACCESSORIES
terminals to power your turnouts. Use the TRACK terminals
to power the LEDS. Use a 470 ohm resistor in series with one
side of the LED circuit and set the speed control to give you
around 9 volts DC. Note that the long wire on the LED goes
to Positive. I would use the positive as the switched side.

You could also, as suggested, use an old wall wart for your
LED power source. There is a
label on every one of them that states the Output as AC or DC
and at a specific voltage and amperage. You might even find
one with an output of around 10 to 15 volts that could power
your turnouts. Some vendors at flea markets have boxes of
them and 5.00 or less.

Don
 

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SB,
If you were to wire it as I suggested, yes you could run the positive out as a buss with feeders to the TO's then you would have two wires returning to the led's. Or as DonR suggested DPDT/monetary switch, which will lessen the amount of wiring but increase the cost!
 

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Discussion Starter #17

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Discussion Starter #18
Someone mentioned that I could put that old cell phone chargers to go use to power my LED's. I'm not the most electronialy inclined here. How do I properly wire them up? I found 2 samung chargers and it says it have 5volt output.
 

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The chargers are likely DC, so you'd need to determine which
wire is POSITIVE or NEGATIVE. Then you'd need a resistor
to drop the voltage to around 2 volts. I'd guess, maybe 50
to 100 ohms. Start with a higher resistance and come down
to the brightness you want. Run the negative wire as a buss
to each LED, the Positive side goes to the middle tab of
your DPDT switches.

A concern is the fractional amperage you'll have from these
wall warts vs the number of LEDs you'll use.
I would have preferred one with 2 or 3 amp
output. They're available at most flea markets.

Don
 

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Discussion Starter #20
Ahhhhh

I have been just trying to get just the switch working. Here is a neat diagram of how I have it wired. When I switch the DPDT one way the switch will move once I activate the momentary. When I switch the DPDT the other way and press the momentary my transformer light almost goes off. To me that is saying there is a short somewhere.

I tried swapping the positions of the Red and Black wire on the switch and no matter witch way the DPDT was the switch would only move one way when Moment. was pushed.

Need a little help :dunno:

https://plus.google.com/u/0/101775083304838081310/posts/a9ff9C7Anx7?pid=6174426758736757330&oid=101775083304838081310

Sorry my pc will not let me upload the pic directly to the thread.
 
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