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LED Lighting question- Push Buttons

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Posted by Hamltnblue on Thursday, June 17, 2010 9:16 PM

 The op should be careful.  Did you originally say the issue was with coil type switch machines?  If so you should be careful not to confuse answers based on tortoise machines.

Springfield PA

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Posted by MisterBeasley on Thursday, June 17, 2010 7:30 PM

Are you talking about Tortoises for the crossovers?  I've never tried it, but a couple of people have suggested putting a two-color, two-lead LED in series with one of the Tortoises.  The Tortoise itself acts as the current-limiting resistor, so you would not put in another one.  With these LEDs, the light is either red or green depending on the polarity, just like the Tortoise position.

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Posted by hwolf on Thursday, June 17, 2010 6:25 PM

What about the Crossovers. At present there are no lights on them. As I mentioned one switch control throws two turnouts. How would I wire these for lights? Bottom photo shows this the best. On those I could use one multi color LED if better. A wiring Diagrahm would be nice.  Thanks in advance. 

Harold

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Posted by MisterBeasley on Thursday, June 17, 2010 5:17 PM

You can use DPDT toggles instead of SPDT toggles.  Just wire one side (3 terminals) of the DPDT as if if were an SPDT, and leave the other side open.

But...

The wiring for the Tortioses will be completely different.  As you know from wiring some already, you cross-wire the corners on the DPDT.  So, your LED wiring would have to be completely removed and replaced.  If that's easy, OK, no big deal, but I prefer not to do something like this knowing it will be replaced shortly.  For one thing, with some of these mini toggles, they really can't take all that much heat.  In general, soldering a connection should cause no problem, but sometimes un-soldering requires a bit more heat and you may find yourself with with a one-and-a-half pole, double-throw toggle.

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Posted by hwolf on Thursday, June 17, 2010 5:06 PM

Ok. Now lets get more complicated.  First, let me explain why I am going to use two lights.  See panel below.

I started with all Push Buttons. As I replace with Tortoise the holes from the push buttons will be  replaced by lights.  Good example is #5. #20 is also getting a Tortoise. Lower right siding has been extended into a passing siding with two Tortoises. Lower left inner circle now has a Tortoise.

Now for the questions. First, how do I wire the Tortoise crossovers? One switch controls two Tortoises.

Second, I would like to use DPDT switches just for the lights where the push buttons are so when I want to change to Tortoises the switches are already in.   Need wiring instructions.

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Posted by rrinker on Thursday, June 17, 2010 2:52 PM

 Then there's the option of using bicolor LEDs for each route, so the lined route shows green and the other shows red. Just saying..

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Posted by richhotrain on Thursday, June 17, 2010 1:43 PM

MisterBeasley

richhotrain
Why use a separate red and a separate green LED?

So far, all of the LED turnout indicators on my panels have been of the dual-color variety.  However, that may not be the best choice, because the meaning of "Red" and "Green" isn't always clear.  Sure, if you've got a main line with a turnout going to a stub industry siding, it's pretty obvious.  But how do you define "Red" and "Green" for a pair of tracks which run parallel, where either one could be defined as the "main" and the "passing siding?"

There are definitely situations where it's a lot clearer to have a separate LED for each branch of the turnout on your schematic panel.  In this case, you could use two greens or two reds, because the location of the lit LED contains information that the color doesn't convey.

I'd imagine that it's probably a bigger issue if you run op sessions with outsiders who may not be as familiar with the details of your layout as you are.

As Ed McMahon used to say, "You are correct, Sir".

 

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Posted by MisterBeasley on Thursday, June 17, 2010 11:53 AM

richhotrain
Why use a separate red and a separate green LED?

So far, all of the LED turnout indicators on my panels have been of the dual-color variety.  However, that may not be the best choice, because the meaning of "Red" and "Green" isn't always clear.  Sure, if you've got a main line with a turnout going to a stub industry siding, it's pretty obvious.  But how do you define "Red" and "Green" for a pair of tracks which run parallel, where either one could be defined as the "main" and the "passing siding?"

There are definitely situations where it's a lot clearer to have a separate LED for each branch of the turnout on your schematic panel.  In this case, you could use two greens or two reds, because the location of the lit LED contains information that the color doesn't convey.

I'd imagine that it's probably a bigger issue if you run op sessions with outsiders who may not be as familiar with the details of your layout as you are.

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Posted by richhotrain on Thursday, June 17, 2010 11:21 AM

richg1998

 

 It can be done as indicated but a lot easier with a single DPDT switch as you can put a single bi-polar green/red LED in series with one lead to the Tortoise and do not need a resistor. Our club does that.

Rich

Rich agrees with Rich here.  Why use a separate red and a separate green LED? Just use a bi-color red/green LED to simplify the task and use less materials in the process?

Rich

Alton Junction

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Posted by MisterBeasley on Thursday, June 17, 2010 6:38 AM

If you want to go the two-toggle route, then you would need a single-pole, double-throw (SPDT) for the lights.  Unlike the turnout control for twin-coils, you do NOT want a momentary contact toggle for this, just a standard up-down, with no center off.  The positive power lead goes to the center post of the SPDT.  Each outer post goes to the anode of one LED.  Connect the cathode of the LED to a current-limiting resistor, typically about 1K, 1/4 watt.  Then the other side of the resistor goes back to the negative terminal on the power supply.

I use dual-color LEDs for some of these.  It's a single LED, with 2 anodes and 1 cathode.  (Unless, of course, it's 1 anode and 2 cathodes.  I'm not sure.)  Depending on which leads you power, you can get red, green or a muddy yellow.

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Posted by jasperofzeal on Thursday, June 17, 2010 6:37 AM

Here is an option for providing LED indication with your twin coil machines:  http://www3.sympatico.ca/kstapleton3/751D.HTM

I've not used these but I do remember someone posting this company's link on the forum.  Hopefully someone out there has used these and can tell you how they work.

EDIT:  I didn't notice but Mr. Beasley already posted the link in a previous message.  I guess my post can just be a reminder of a possible solution.

TONY

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Posted by hwolf on Wednesday, June 16, 2010 4:56 PM

Thanks to you and Mr Beasley for the focus. As I was driving home from work I thought of the same idea of just puttng in the lights with a switch. Do I use a DPDT or SPST to change the lights from Red to Green?  I basic wiring diagram would work wonders.  Thanks

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Posted by Hamltnblue on Wednesday, June 16, 2010 2:15 PM

 As noted above, if your push buttons are controlling twin coil switch machines your options are limited.  You could just put a switch next to the push button to manually control the light color whenever you change the switch position.  The latching relay option noted above will work but the problem is that it will let go and not come back on when you cycle power to the layout.  There might be a 3rd party add on to the swtich machines to provide contacts but I'm not aware of any.

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Posted by MisterBeasley on Wednesday, June 16, 2010 1:39 PM

I think the OP has muddied the water a bit by even mentioning Tortoises.  A careful reading of his post indicates that he has already successfully wired Tortoises with LEDs, but he now wants to go back and retrofit his older twin-coils.  Did I get that right?

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Posted by richg1998 on Wednesday, June 16, 2010 1:28 PM

 It can be done as indicated but a lot easier with a single DPDT switch as you can put a single bi-polar green/red LED in series with one lead to the Tortoise and do not need a resistor. Our club does that.

Rich

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Posted by MisterBeasley on Wednesday, June 16, 2010 12:00 PM

I'm assuming that what you've got is push buttons used to drive an Atlas, Peco or other twin-coil switch machine.  These machines typically do not have contacts built into them.  Since the pushbuttons are momentary, they can't be used to drive LEDs, either.

One solution is to use a latching relay circuit in parallel with the switch machine.  This is essentially what an Atlas relay unit is.  These are expensive, though.  You can buy latching relays from electronics places for less.

But, take a look at these as another option:

http://www3.sympatico.ca/kstapleton3/751D.HTM

I have a few of them, and they work as advertised.  He will sell assembled units, or for less money you can order a bag of parts and assemble a bunch of them yourself.

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Posted by firstbelt on Wednesday, June 16, 2010 11:39 AM

There are some connections to indicate switch position, that you'd run LEDs from.  A little snooping around got me this, but it doesn't seem to be what you want.

Tortoise diagram

The Circuitron web site says it has DPDT contacts.  If you have an ohm-meter, you could check out which are open and closed in either switch position and probably figure it out yourself.  Or perhaps it's on the Tortoise wiring diagram that came with the machine.

As with a relay, the switch machine has a coil for the mechanical action of the contacts.  The coil drives the switch points.  The DPDT contacts would turn on/off panel indications.  The Circuitron photo shows 8 connections, 2 would be for the coil.  That leaves two sets of 3 connections for double-throw contacts.

Of course, it would depend which kind of turnout you're using with the machine (left or right).  You could use some incandescent bulbs hooked up to a battery or power supply, to test out what the machine is doing.  After you figure it out, hook up the desired LEDs in place of them.  I assume you have the required resistor for them... ?

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Posted by retsignalmtr on Wednesday, June 16, 2010 11:20 AM

What type of switch machines do you have? Do they have any electrical contacts to route the power for the LED's?. I can't post a circuit drawing here. Maybe someone else can.

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LED Lighting question- Push Buttons
Posted by hwolf on Tuesday, June 15, 2010 8:01 PM

I am installing seperate Red & Green Panel LED's with my new Tortouse machine (NO PROBLEM). I still have several switches controled by PUSH BUTTONS. Can I install seperate lights (RED & GREEN) on these that will light showing only the direction the turnout is in? If so, please show me the wiring to do this.  Keep it simple.  Thanks in advance for your answers.

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