For my Allegheny & Cumberland layout, I’m planning on installing a few of the two light dwarf signals from NJ International. I already have in place block signals using the Atlas Signal System in certain areas, but for these dwarfs,they’re more for " show & effect ", rather than for operations. My question is … is there a quick & easy way to wire these, using a toggle to select which color LED that will be lit ? I already have some spdt toggles, so I’d have an on-off-on control of the signals, IF that would be the correct toggle for what I want. IF it is possible & I THINK I know how the wiring would be … how would it be wired just the same ?? Thanks for any help !
The signals on my layout are wired up as turnout position indicators - mostly on the frog end, and they show which path is selected. To do this, I use either a separate relay or a mechanical attachment to the switch machine. These are effectively Single-Pole, Double-Throw toggles.
I’m using dual-color red/green LEDs for my signals. Are yours dual-color LEDs like these, or separate bulbs for each color?
Well apparently this isn’t going to be as easy as I perhaps thought. I just recently ordered the signals, so I don’t have them yet & therefore I dunno if they’re dual or seperate bulbs. All of my turnouts are manuel, so that’s why I was thinking of possibly just wiring the signals along with its resistors & then to the toggle & there to the power source. I’m hoping there’s options because I don’t wanna mess with block detectors & the such for this project. The model # is the NJ International 2100 signals if that helps. By looking at the picture of it, it looks like it might be seperate since there are 3 wires comming from the housing.
well, just do like Mr. B, but conect the manual throw bar to a SPDT switch. so as you push/pull on the control arm, it moves the switch points as well as the signal switch to change the color of the lights.
Thanks for the replies guys, but still, that’s not what I’m looking for. These signals will be placed in my yard throats, so it’s possible to have all red… or green lights lit, depending on traffic. That’s why I want them to be wired independantly from the track. I just wanna make sure I don’t end up frying anything if I wire them the way I’m thinking I would.
I, and my prototype, use dwarfs as turnout direction indicators, so the 2 dwarfs controlling movement into the frog end of a turnout always have opposite indications depending on which way the points are thrown. Likewise, the dwarf at the point end will display more restrictive for the, “Reverse,” point setting, and less restrictive for the, “Normal,” point setting. All three dwarfs for a single turnout, and the turnout motor or ground throw, would operate together.
In model form, this can be done with one set of SPDT contacts on a switch machine, a separate SPDT switch or a SPDT switch mechanically connected to the ground throw. The disadvantage of a separate switch (not connected to the ground throw) is that there are two separate controls and one or the other could be overlooked - especially by a novice operator.
Personally, I use toggle switches at the fascia line, mechanically linked to the points, to control manually thrown turnouts and all associated electricals. Turnouts controlled from different places are fitted with 2-coil switch machines and signal circuits are routed through the switch machine contacts.
Chuck (modeling Central Japan in September, 1964 - with dwarfs within yard limits)
Wire the two LEDs in series Anode to cathode. The LEDs will have one lead in common. Use a split power supply. Ground goes to the two single leads. + and - to each end of the SPST switch. Center of switch through 1k nominal resistor to common LED connection.
Better solution is to use two resistors - one in series with each single LED lead. This will allow you to use different resistance values to adjust for similar brightness.
Adaptable to bi-color LEDs too.
Karl
Thanks again. I just found this diagram that shows what I want to do for the most part. It shows using a DPDT toggle, so I dunno if it has to be exaclty like that. Let’s pretend this has nothing to do with model railroading … just an attempt to light up a red or green LED using a toggle to select which color I choose …
In the end, it will be a simulation of block detection which would be less expensive & less of a hassle of wiring up normal signal controls. With that said, I’m looking for reasurrance I suppose that this would work for what I’m wanting to accomplish. For the signals I’ll be using, two resistors come with each signal. Any suggestions on this approach ?
2 LEDs (red and green), SPST, 9V power supply, 1K resistor. You may have to fool around with polarity to get the LEDs to light but it will work. Forgive the drawing, it’s late.
Thanks for the help, I really appreciate it. I am curious as to how we get a 9 volt supply. Also, why isn’t the long leg of the red connected to the short leg of the green ? Is that because it’s due to being a 9 v hook up ?
This is a prety good diagram of how to do it. Now to let this tshow which way the TO is thrown (what I was trying to explain before).
- Drill two holes in the throw of the switch (assuming it’s plastic)
- connect your pull rod to one hole, and the TO throwbar to the other hole (assuming of course, this is possible. I don’t know what your control mechanism looks like)
When you set the TO to the diverging route, you’ll throw the switch below your benchwork, and the lichts will change…
This is what had in mind… The Blue line is the pushrod to your fascia panel, and the red line is the turnout throwbar.
All you require is to turn on a LED when you toggle the SPST switch. You don’t really need all all the fancy criss-cross wiring to invert polarity. That is good if you are running a dual color LED . From what I see, you’re not, just the red and the green.
Use a 9V (wal-wart) power supply if you’re only doing this for a few LED. More LED’s, more amps.
I forget the long lead, short lead thing. Just try it, you can’t blow the LED as long as you put the resistor in the circuit.
Thanks again guys ! UpNorth, I like your diagram, yeah… just switching red & green lights is all I want to do. In due time I plan on quite a few perhaps, so I’ll use an extra MRC power pack for my DC power source. So I’ve learned something new, that’s cool. This weekend I’ll buy a few & play around with them !
Ok, one more question. Today I made a mock up using the diagram below. The only difference was that I used a 12v DC powerpack for power & I used a SPDT toggle that I already had. I want the on-off-on capability anyway. The lights worked like a charm. I stopped at Radio Shack yesterday & though they had sub miniature red bulbs, I had to buy a larger green bulb. Anyway, just as I somewhat expected, the resister became hot while having either bulb on using the 12v. I tried a 9v battery for the hell of it & that worked too, but the resister did not get hot. I figured it got hot the other way was due to more voltage for that one set of bulbs. I plan on having quite a few more signals hooked up once I implement this, & I’m thinking that will disperse the heat when I do that & things will be ok. Is my thinking correct ?