I'm having a problem. I'm trying to convert a lionel 6-38511 F7 to LEDs, specifically the number boards and cab light (which are connected to track power) everything else is already LEDs. I wired the lights in but only one lights up. Any ideas?
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Try switching the wires on the one that's not lighting.
The output is half-wave DC in command mode, so Lenny is correct, one is reversed in polarity.
FWIW, you only need one resistor, put a 330 ohm resistor in series with one of the leads before the split.
gunrunnerjohn posted:The output is half-wave DC in command mode, so Lenny is correct, one is reversed in polarity.
FWIW, you only need one resistor, put a 330 ohm resistor in series with one of the leads before the split.
Alright. I'll fix them. Thanks!
I think I'm overthinking this. I reversed the polarity and used only one resistor but the other light still doesn't light up.
How did you reverse the polarity? Did you switch the two wires on the unlit LED
romiller49 posted:How did you reverse the polarity? Did you switch the two wires on the unlit LED
Yes.
Could the LED simply be bad? Are they different types of LEDs?
gunrunnerjohn posted:Could the LED simply be bad? Are they different types of LEDs?
It could be. I got a pack of 100 LEDs on amazon, which is what I was using for this test.
I suggest starting with two new LED's, wire them in parallel with + to + and - to -. Put the resistor in series with one of the leads. The + side connects to frame ground for TMCC locomotives, and the - side connects to the lighting output. Also, if this is not an ERR equipped locomotive, you'll need a .01uf capacitor across the light output from the TMCC board to trigger the triac for the lighting.
gunrunnerjohn posted:I suggest starting with two new LED's, wire them in parallel with + to + and - to -. Put the resistor in series with one of the leads. The + side connects to frame ground for TMCC locomotives, and the - side connects to the lighting output. Also, if this is not an ERR equipped locomotive, you'll need a .01uf capacitor across the light output from the TMCC board to trigger the triac for the lighting.
Alright, I will do that. The engine I'm working with is a legacy 6-38511 F7 set. I'm starting with the non powered unit first.
Got it working
Does, anyone know if th number board lights ar connect d directed to AC power on the first run of sd70’ s. Two grain of wheat bulbs are connected independent to the lighting circuit board. I assume these are in parallel to track power.
What is the best game plan for number board leds. This is a legacy engine.
Trainlover9943 posted:Got it working
What was the solution?
shawn posted:Does, anyone know if th number board lights ar connect d directed to AC power on the first run of sd70’ s. Two grain of wheat bulbs are connected independent to the lighting circuit board. I assume these are in parallel to track power.
What is the best game plan for number board leds. This is a legacy engine.
I'd use two surface mount LED's in opposing polarity and a 470 (or larger) 1/4w resistor in series to track power. This will give you plenty of cool light that will have a wide angle for even lighting.
gunrunnerjohn posted:Trainlover9943 posted:Got it working
What was the solution?
I wired them the way you said in the above reply. I just have to take the LEDs to the engine now. Since the lights were bulbs (for the number boards and cab light, each is wired to track power) is there a positive or negative wire or just pick one and use it?
If these are coming from track power, then you can connect them either way, track power is full-wave AC.
gunrunnerjohn posted:If these are coming from track power, then you can connect them either way, track power is full-wave AC.
Alright sweet. I'll put it in and report back.
Trainlover9943 posted:gunrunnerjohn posted:If these are coming from track power, then you can connect them either way, track power is full-wave AC.
Alright sweet. I'll put it in and report back.
This seems to be the never ending project. There are four wires, hot and common to each bulb for the cab lights. I got my ohmmeter out and attached two wires together only to get continuity with both the hot and common connections(pick up roller and wheel tested). In addition, I separated each of the wires and tested and the same thing happened. The other pair of wires had no continuity on other of the two earlier tests. Not sure what to do now.
Maybe, the lights are wired in series via the board?
shawn posted:Maybe, the lights are wired in series via the board?
Maybe. I forgot that the cab lights are connected to the board for control via the remote. The number boards, which I'll work on next, are track powered.
Trainlover9943 posted:shawn posted:Maybe, the lights are wired in series via the board?
Maybe. I forgot that the cab lights are connected to the board for control via the remote. The number boards, which I'll work on next, are track powered.
Mine are connected to a pcb. But, they are still connected to track power via the harness.
The cab lights are connected to the "feature" output of the R4LC, so you'll want the negative to go to frame ground and the positive to go to the existing wire from the motherboard.
FWIW, the number 6-38511 doesn't map to any Lionel product.
gunrunnerjohn posted:The cab lights are connected to the "feature" output of the R4LC, so you'll want the negative to go to frame ground and the positive to go to the existing wire from the motherboard.
FWIW, the number 6-38511 doesn't map to any Lionel product.
My bad its 34511. How do I know which one (of the four wires) is the frame ground and the positive, use the ohmmeter?
Yes, the ground lead will obviously be connected to the wheels/frame. The lighting output will not be. 
The reason I was looking for the product number was to verify when it was made, the 2007 stuff still used the modular boards, so the cab lights were connected to the R4LC.
gunrunnerjohn posted:Yes, the ground lead will obviously be connected to the wheels/frame. The lighting output will not be.
The reason I was looking for the product number was to verify when it was made, the 2007 stuff still used the modular boards, so the cab lights were connected to the R4LC.
Ah alright. I found that both pairs of leads are connected to the board. Is that normal? One pair is connected to the ground pin, the other to the RL pin. The one that is connected to the RL pin is also connected to the 3rd and ground pins on the board.
Hard to say, without seeing the board and ringing it out, don't know what the other leads are connected to.
gunrunnerjohn posted:Hard to say, without seeing the board and ringing it out, don't know what the other leads are connected to.
Ah. I'll keep working on it, if I get it to work, I'll report back. Hopefully I'll get it going.
I know I have it wired correctly since I have continuity with the pins on the board and the respective pins on the R4LC. Just not sure why the lights don't work.
Did you add the .01 caps I mentioned?
gunrunnerjohn posted:Did you add the .01 caps I mentioned?
I need to order them. I will and report back when I do, you have a link to them?
Try lighting the lights with a 9V battery on your harness. If they don't light, reverse the connections. They should light on DC, if not there's something wrong right there.
gunrunnerjohn posted:Try lighting the lights with a 9V battery on your harness. If they don't light, reverse the connections. They should light on DC, if not there's something wrong right there.
Will do.
They work
In that case, I'd suspect the missing load caps are probably the issue. The triacs need either a resistive or capacitive load to trigger, the LED doesn't conduct any current until around 2.5 volts or so, so the triac doesn't see any load.
gunrunnerjohn posted:In that case, I'd suspect the missing load caps are probably the issue. The triacs need either a resistive or capacitive load to trigger, the LED doesn't conduct any current until around 2.5 volts or so, so the triac doesn't see any load.
Ah. So the .01 caps will fix the issue. I'll get to ordering them.
Well, they should if everything else is wired properly. Since the LED's work, they're not the problem.
gunrunnerjohn posted:Well, they should if everything else is wired properly. Since the LED's work, they're not the problem.
Cool. Yeah, the LEDs do in fact work which is half the battle.
Trainlover9943 posted:gunrunnerjohn posted:Did you add the .01 caps I mentioned?
I need to order them. I will and report back when I do, you have a link to them?
Trainlover9943 posted:gunrunnerjohn posted:In that case, I'd suspect the missing load caps are probably the issue. The triacs need either a resistive or capacitive load to trigger, the LED doesn't conduct any current until around 2.5 volts or so, so the triac doesn't see any load.
Ah. So the .01 caps will fix the issue. I'll get to ordering them.
What did you end up ordering? Or do you need assistance identifying a suitable part? These are 5 cent components so you'll pay way more for shipping! It can be overwhelming on eBay, Amazon, etc. if you search for ".01uF capacitor" as there are hundreds or thousands of choices!
stan2004 posted:Trainlover9943 posted:gunrunnerjohn posted:Did you add the .01 caps I mentioned?
I need to order them. I will and report back when I do, you have a link to them?
Trainlover9943 posted:gunrunnerjohn posted:In that case, I'd suspect the missing load caps are probably the issue. The triacs need either a resistive or capacitive load to trigger, the LED doesn't conduct any current until around 2.5 volts or so, so the triac doesn't see any load.
Ah. So the .01 caps will fix the issue. I'll get to ordering them.
What did you end up ordering? Or do you need assistance identifying a suitable part? These are 5 cent components so you'll pay way more for shipping! It can be overwhelming on eBay, Amazon, etc. if you search for ".01uF capacitor" as there are hundreds or thousands of choices!
I found them on a previous post of mine. These are the ones GRJ posted the link for. Will these work? https://www.digikey.com/produc.../BC2662CT-ND/2356876
10,000pf = .01uf
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