Tortoise and bicolor LED wiring question

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I

ianacole

Well-Known Member
I am struggling with understanding how to wire a 3-lead, bicolor LED to a tortoise switch machine. In searching I found a lot of discussion about it, but being a visual learner I need something more. Do I have the attached diagram wired correctly to account for a 3-lead, common cathode, bicolor LED?

Thanks!

Ian
 
Ian, I first have to assume you are showing only half your switch.
You need to supply the three lead led with hardwired Neg on the common and switchable positive on each color lead, e.g. you throw your switch, you also switch positive from one color side of the led to the other (neg stays same). The built in switches of the Tortoise are ideal for this setup and is what I use.

Don't forget to add your resistors. One will work on the negative (common) side, but it is recommended to have one on each color circuit and a must if you do the following: Also, if you want yellow, say to slow a train to make the diverging route, you can wire green to be permanently connected to positive (always on), then when the turnout is switched to diverging the red comes on giving you a result of yellow. You can do the same with red instead of green if that's what fits the situation.
 
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Thanks guys. I'm not planning on doing any signaling or control, only indication with these. I have two-lead, single-color LEDs working just the way that I would like to, but it requires twice as many LEDs ... hence the desire to move to the bi-color.

Is it possible to wire a 3-lead, Bi-color LED into this circuit, or should I be looking for 2-lead bicolor LEDs?
 
Thinking about it you will need two leg LEDs as the cathode is the common on three leg LED.
 
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Just use the built-in Tortoise switches (term 2,3,4/5,6,7). That's what they are there for ;). All you have to do is tap off the unswitched power somewhere before the Tortoise. When the Tortoise motor moves, these switches open and close. Trust me, I've done dozens :)

Let me go ahead and add:
for three lead LED
wire pos power to terminal 4,
wire red led to terminal 2
wire green led to to 3
wire LED common to neg. ( this can be wired direct to a neg terminal...better.)

or use the other switch: 5,6,7
There another way using the circuit term 1 and 8, but you must install additional diodes, more wiring, etc...PIA :D
 
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RexHea said:
Just use the built-in Tortoise switches (term 2,3,4/5,6,7). That's what they are there for ;). All you have to do is tap off the unswitched power somewhere before the Tortoise. When the Tortoise motor moves, these switches open and close. Trust me, I've done dozens :)
Click to expand...

So, something along these lines, ignoring current direction and necessary resistance for the moment (I've included the tortoise pin-out as well):
 
Its not ignoring current direction, as the built in switch places the positive on one color teminal or to the other (dependent on the motor moving) , with the neg permanently wired to the common of the LED.

ADD: The power does not come from the 1 and 8 lines. It would come direct from your power source on the top of your drawing, independent of your Tortoise activate toggle/push button/decoder/etc.
 
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I only meant that I was ignoring current in that I didn't pay attention to whether or not I attached the appropriate 12VDC terminal to the Cathode in my diagram, but I think I did just by luck. ;)
 


Well, that was dumb on my part :rolleyes: No potential difference there! Thanks!! I had never thought through the other 6 pins of the Tortoise ... just ASSumed they were strictly for frogs and signaling, not really paying attention to the fact that they're just switches with leads.
 
Ian are you running DCC on the layout?
If so I highly (very highly) recomend picking up an NCE "switch 8" to power the tortoises.
You can throw turnouts from anywhere from the throttle and the bicolor LED's just wire in line with the switch power, no resistor needed.
One LED will show red or green and two wired opposite of each other on the same line will show red and green on either track.
Not sure I explained that right but here's how mine looked back when I started:
http://www.youtube.com/watch?v=8fIuKSpuJ2c
 
I am running DCC, NCE's product nonetheless. Those Switch 8's look quite nice...but I'd need 3 of them at $60 a pop. Let's see if I can work on the financial manager ;)
 
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