LED lighting

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wayles3

Member
Is there any way to add red and green led lights for detection and signals at trackside and at the control panel using the old school Atlas snap relay #200 and the ez track turnouts using the Atlas switch controls? All of this is not on a dcc system.
 

Iron Horseman

Well-Known Member
Sure there is, that is kind of its whole purpose in life. It is just a relay. You need a power supply for the red and green lights and connect it to one of the the relay outputs. If you choose LEDs for lighting you will need a resistor for each. There are many diagrams for it on-line. Search for "Atlas Snap Relay 200 Instructions".

Example: And, No, you don't need the capacitive discharge. it is just and example.
simple_layout_5-1024x800.png
 

Smudge617

Well-Known Member
Sure there is, that is kind of its whole purpose in life. It is just a relay. You need a power supply for the red and green lights and connect it to one of the the relay outputs. If you choose LEDs for lighting you will need a resistor for each. There are many diagrams for it on-line. Search for "Atlas Snap Relay 200 Instructions".

Example: And, No, you don't need the capacitive discharge. it is just and example.
simple_layout_5-1024x800.png
Am I missing something here, I've at least 14 ground (dwarf) signals, all wired up to 12v and working, is there a particular aspect of the Atlas snap switch that needs resistors on both negative LED lines, I only use one, on the positive, I'm aware it doesn't matter where on the circuit you place the resistor, but why use two when one will do?
 

D. Soppy

Member
Am I missing something here, I've at least 14 ground (dwarf) signals, all wired up to 12v and working, is there a particular aspect of the Atlas snap switch that needs resistors on both negative LED lines, I only use one, on the positive, I'm aware it doesn't matter where on the circuit you place the resistor, but why use two when one will do?
One resistor on the common lead will work as will a resistor on each of the negative leads . The only time it will make a difference is if the LED's are both on at the same time . I'm using a single LED that is red/green . The red is a lot brighter than the green . I used a higher value resistor on the red wire so it is now the same intensity as the green portion.
 

Smudge617

Well-Known Member
One resistor on the common lead will work as will a resistor on each of the negative leads . The only time it will make a difference is if the LED's are both on at the same time . I'm using a single LED that is red/green . The red is a lot brighter than the green . I used a higher value resistor on the red wire so it is now the same intensity as the green portion.
Now it sense :)
 

Iron Horseman

Well-Known Member
Am I missing something here, I've at least 14 ground (dwarf) signals, all wired up to 12v and working, is there a particular aspect of the Atlas snap switch that needs resistors on both negative LED lines, I only use one, on the positive, I'm aware it doesn't matter where on the circuit you place the resistor, but why use two when one will do?
Not missing anything. As you note and the other poster stated it can work just fine. I used to use a single resistors. Then I when was using them for hot frog indication I noted that a single common resistor could allow both LEDs to light in certain circumstances. When I switched to one-per they went back to what I considered "normal", both LEDs not lighted in that same circumstance.

Plus so much easier for folks without electrical knowledge to understand, without having to explain a "common" type wiring system to them.

Then another big one, I realized that resistors are costing less than .01 each. At that "price" why I don't have to worry about and analyze the exact circuit. I can just use one resistor for each LED.
 

Smudge617

Well-Known Member
Not missing anything. As you note and the other poster stated it can work just fine. I used to use a single resistors. Then I when was using them for hot frog indication I noted that a single common resistor could allow both LEDs to light in certain circumstances. When I switched to one-per they went back to what I considered "normal", both LEDs not lighted in that same circumstance.

Plus so much easier for folks without electrical knowledge to understand, without having to explain a "common" type wiring system to them.

Then another big one, I realized that resistors are costing less than .01 each. At that "price" why I don't have to worry about and analyze the exact circuit. I can just use one resistor for each LED.
Yeah, that makes sense :)
 

diesel

Active Member
Just one thing though... you said detection. There is no track occupancy detection with this, only switch position indication. You can add a dwarf so there are two facing the points, connect the red/green in opposition (by wiring them in parallel), so the through track is green and the other is red. On the points end, it will always be a clear indication without any occupancy detection. But it's cheap and easy.
 




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