They are bicolor LEDs, so 2 back to back, depending on the polarity either the green or the red lights up (or other colors, there are other combos available now).
The same system would work with your wiring method, the LEDs would just go in series with the line leading from the SPDT toggles to the Tortoise motor. They key is that the Torise motor draws less current than the maximum allowed for LEDs, so you cna place LEDs in series witht he motor wires and not need any resistors. Makes for simple panel indicators or you can disguise the LED as switch lanterns and put one right at the turnout. Plus it means both sets of contacts on the Tortoise are still available for other things. Downside is it reduces the voltage to the Tortoise (not always a bad thing), and the LEDs light up dim while the Tortoise is moving and then brighten when it stalls - also not always a bad thing.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
If the Tortoise moves, then the circuit is OK. You showed two LEDs back to back, so only one is lit, thus you only have one LED in the circuit, the other is, as far as the circuit is concerned, not even there. Unless of course you have two LEDs lit.
LION DOES NOT DO THINGS THAT WAY.
LION has a HARD GROUND common running around the layout. One leg of turttle is soldered to the ground. Him cannont get away from the LION!
LION uses SPDT switches, one side of switch is -12vdc (Normal Position) or +12vdc (Reversed Position). The switch common is what I call the "stingger". It drives the terripin back and forth, it also will enervate any number of LEDS, relays and other appliences providing indicaation, signalling, and signal and track logic.
And LION only needs to run one wire to the hard-shelled slow-poke. On Layout of LION, with hundreds of wires, saving costs on wiring is a very big deal. ONE wire per turnout is enough. (After all, each station platform requires FIVE wires for the block signals and analog automation used by said LION. And him has lots of stations.
ROAR
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
There are two LEDs in the circuit? The ~4V drop would be about right then, it's about 2.1V per LED for an ordinary colored LED. The Tortoise will be slow, but should be a lot quieter running on 8V. I would not go to a 16V wall wart - possibly a 14V one would be fine. 8-10 volts is kind of a sweet spot for a Tortoise where it still has enough power to hold the points but is much quieter than when using a full 12V. Just be sure that if you add more Tortoises, you install 2 LEDs with each of those as well, as 14V and 16V exceed the Tortoise rating.
The only other thing you can do is wire them to the contacts on the Tortoise, using a seperate power supply and resistors, so there is nothing between the toggle switch and the Tortoise motor connections. But this means a lot more wiring and complexity.
I was messing around with a test circuit tonight and confirmed that the LEDs are sucking 4 volts from the motor. I'm using a 12v wall wart. Without the LEDs in the circuit, I measures a full 12 volts going to the motor. With the LEDs, it dropped down to around 8v. Not sure if there's any way to rewire it a bit to get more volts to the motor. I don't mind sacrificing LED brightness if I have to.
I suppose the alternative is to get a 16v wall wart? Any harm in doing that?
Thanks for the reply. If I did want to get more power to the motor, how could I go about doing this? Would I have to use more than 12v to start with? With 12v, 2 leds, and a motor, is this the most power I could get out of it?
I played around with this a bunch back when I got started. The less volts that the Tortoise sees the slower it will go, so adding an LED will slow it down a bit. But as long as the Tortoise goes to the end of the stroke and stays there it dosn't really matter. For turnouts that I can't see very easily I put two bipolar LEDs in series to the Tortoise (one at the panel and one at the turnout) and and they still work just fine.
You won't see any difference in the speed as you add tortoises. Since they will all be wired in parallel you will get the same voltage to all of them, and they will all run at the same speed as the first. And they pull very little power so there is no problem putting a bunch of them on the same power supply.
Huntington Junction - Freelance based on the B&O and C&O in coal country before the merger... doing it my way. Now working on phase 3. - Walt
For photos and more: http://www.wkhobbies.com/model-railroad/
Bumping this up 8 months since my last post. I haven't been able to work on my layout for the last few months, but want to get back into it again.
Can anyone help me with this last question? The bipolar led setup is working good for me now, but it seems the motors aren't getting enough juice. When I tested everything at my workbench, without the LEDs, the motor went nice and fast. Now, with the LEDs in the circuit, the thing is slow as...a tortoise. I measured the voltage at the motor, and it's around 8v. I'm using a 12v wall wart. Should the motor have more voltage? What can I do differently?
I'm also concerned of what will happen when I start connecting more motors to the circuit. Any help would be greatly appreciated!
H
Hey guys - I have a follow up to this post/question. I have wired up my first turnout using the diagram provided here. It works great. One thing though - I feel like not enough power is getting to the tortoise for some reason. When I was playing around with the LEDs, the motor moved pretty fast, and had a lot of force on it - to the point where I couldn't even move it manually if the motor was powered.
Once I got the LEDs in the circuit, it moves much slower and doesn't seem to have as much force as before. This is with only one motor in the circuit too.
Should I change something so that I get more power to the motors? I'd say it takes a good 2 seconds for the switch to get completely thrown. Is this normal? I am using a 12v power supply.
Thanks!
Amazing, thats exactly what I needed. I knew it had to exist but wasn't able to find it. Just ordered one to check it out.
Try Miller Engineering #4805 Distribution Block. The pic comes from M.B. Klein's "Model train Stuff" website.
Dante
Sorry-couldn't post the pic, but here's the link:
http://www.modeltrainstuff.com/Miller-Engineering-Power-Distribution-Board-p/mil-4805.htm
You can also get longer jumpers. For example, Radio Shack has 8 position jumpers. You can stack them for longer runs.
Joe
To turn 2-row barrier strips into bus connectors (one for positive DC, another for negative) for my DPDTs in my control panel, I used these. So a 2 row, 8 column barrier strip becomes a bus for 16 connections. You could use a piece of thin wire wrapped across one row instead.
http://www.allelectronics.com/make-a-store/item/jmp-24/jumper-for-ts-200-barrier-strips/1.html
Paul
Modeling HO with a transition era UP bent
Thanks Randy. I guess my question is actually about what you use for that bus and how you connect all the other wires to it. For my dcc bus I'm using scotchlok connectors. I can't see attaching 20 of those inside the control panel. I thought they made terminal strips that act like a bus but can't seem to find that - maybe because I don't know what they're called. Was considering taking a strip of metal and putting screws through it every few inches then attacking the wires to those.
Is there some kind of product that accomplishes this?
Run a bus line from the power supply along the bottom of your control panel, and have all the wires to the switch motors exit at the top. Or vice-versa. Drop two wires from the toggle to the bus for the input side of the circuit. This will keep the input wires and the output to the switch motors seperated and looking neat. Tag the wires to the switch motors with labels, and cable them together with velcro wire ties (not the plastic kind - you generally have to cut those off and use a new one if you need to change anything. The velcro ones, if you add another wire, you just open up and re-wrap). There are also anchors that you can screw into the back of the panel to hold these in place, so there is a neat line growing ever thicker going across the back of the panel, and you have only one bundle of wires going out to the layout. This is why you need labels, , or alternating wire colors, and the velcro, so you can hook up one at a time but in the end have everything cabled together looking neat. If your panel swings up or down, or swings to the side, then the wire needs to exit near the hinge and have enough slack so that you can open the panel fully.
I got it now. Just ordered a power supply, and a few LEDs and switches to experiment a bit.
On last question on this topic - how do you guys distribute the power from a power supply like this? Seems my power supply, and all of the wiring to and from it and the toggle switches will all be located mostly inside my control panel. To avoid a mess of wires, I was thinking of wiring the power supply to some sort of distribution block, and then attaching all the wires from the switches to the block - either by screwing in, with spade connectors, etc.
I can't seem to find a block or strip that would allow me to do this? Most of the ones I see are barrier strips, that isolate each connection from the next. Do I need to use one of these with tons of jumpers, or is there a better solution? I will have about 15-20 turnouts, so it will be a lot of wires inside that control panel and I'm trying to figure out the best way to keep it neat and tidy.
Thanks again for all the help.
Wires like Mr Beasley's diagram? yes, 2 wires to each switch machine - they can be pairs out of phone or netwrok cables, the current is very low. No central bus other than inside your control panel to provide the inputs to each toggle switch.
No resistors needed. Things in series share current. The Tortoise motor is 15-18ma, thus LEDs wired like that also get 15-18ma. Which is well within the safe range for the LEDs.
Ok, so if I wire it in this way, I won't really have a central DC bus running through the layout, right? Each motor would just have it's own set of two wires running back to the panel area? I was thinking that there would be a central DC bus that each motor assembly would tap in to, but it makes sense that at least some wiring would have to go back to the panel, per switch.
And for the LEDs, do I need any resistors in this configuraiton? I can never get that straight. Should have paid more attention in my engineering class.
Thanks again,
Wayne
Yes, this diagram does use 2 LEDs, but you can simplify it with just 1 LED in the same place if you prefer.
If you're going to have a central panel, they you will need just 2 wires running from the panel to each Tortoise machine. In the diagram, the power supply, DPDT toggle and LED or LEDs would be at the panel, and only the 2 wires need to run to the Tortoise from the panel.
If you are planning to power the frog from the Tortoise, that can be done locally using feeders from your track bus and a single wire from the Tortoise to the frog.
It takes an iron man to play with a toy iron horse.
MisterBeasley - The diagram is extremely helpful. I just have two questions about it. Seems I need things spelled out exactly for me. :0
You said that when the polarity of the switch changes, the bi-color LED will change. If I use a 2-pin bi-color LED, what do both pins get attached to? In the above diagram it looks like there are 2 LEDs which I guess is slightly different.
My second question - If I wire it as above, would I have one DC bus running through the layout? I plan on having a central control panel that houses all the LEDs and toggle switches - and I imagine the power supply will be in there too. How can I set this up with the least amount of wiring? I'm trying to avoid a situation where I have 4 or 5 wires going back and forth to the panel for each turnout. I was imagining having one DC bus running through the layout, and then having each turnout wiring assembly tap into it - but I'm not sure how the toggles and LEDs come into play then.
H, A sketch of what's working well for me, taken from the Tortoise Instruction sheet, but powering switch machines only. The single red/green bi-polar LED saved panel space, no resistor needed, torti takes care of that. SPDT toggles and buss simplifies wiring too.
Of course there is the cost of two power sources, think I paid about $15 each from All Electronics. I've shorted the circuit briefly a couple times, lucky no harm done, but maybe I should think about fuses.
I also have all my layout power hooked to a master wall switch, when train time is over I kill the switch, piece of mind thing.
Regards, Peter
Here's one, 12V, 2amp, and it's regulated - so it puts out 12V (or at least really close) over the whole laod range
http://www.amazon.com/Power-Adapter-2-1mm-Regulated-Supply/dp/B00DGG7E36/ref=pd_sim_sbs_e_5?ie=UTF8&refRID=1WG2AFV7MW9D3X694676
and it's cheap. Plenty of power for 20-30 Tortoises and lots of LEDs to light up buildings and streetlights.
Tortoise plus the series LEDs draw no more power than the Tortoise alone - 15-18ma.
Since wall wart power supplies like this typically have a fusible link inside to keep from burining down your house - if you short the output, that's usually it for the power supply and you have to get a new one. So what you should do with something like this is add some fuses before the Tortoises and the building lights. That way if you short something, or attach too many structure lights, the fuse will blow and not the power supply. I'd make two circuits, keep it simple, each with a 1 amp fuse. One feeds the Tortoises, one feeds the other lights.
Tortoise runs on DC. LION prefers to use them with a common ground and then use a SPDT toggle to select between (+vdc) and (-vdc). You only need ONE wire to each turnout that way (and one ground bus around the layout.)
Best Advice: Throw out the instructions that come with the tortoise, and use my instructions...
The model is Powertech II - Locomotion 2500. I don't think it has any control over the pulse.
Can someone recommend a good power supply for what I'm doing? Would need something that can power 20-30 tortoises and accompanying LEDs. If I have other accesories in the future, like lit structures, etc, would be nice to use the same supply as well. Thanks for all the help everyone.
H, My MRC powerpack is an old Railmaster 2400 with a pulse power switch. Just for grins I hooked it up to a Tortoise mach a bit ago.
Randy is correct about the cause of the buzzing being the pulse power, the Torti buzz is only with the pulse power switch on, buzz stops with pulse power switch off.
good luck and regards, Peter
The buzz is probably because the variable DC has pulse power - what model MRC power pack do you have? If it has a pulse power switch, make sure it's off. If it is of the automatic pulse type, there's not much you can do. A 4700uF 35V capacitor would probably smooth the pulses out - however two things - electrolytic capacitors are polarity sensitive and will can literally explode if run backwards, so check the polarity and also never touch the direction switch after it's hooked up. And applying filtering will raise the voltage a bit, so check the voltage you are getting after connecting a capacitor. You might have to turn the speed knob down a little.
Probably easier to just go get a 9V or 12V (12V if you are going to add the indicator LEDs) DC wall wart. A 1 amp one can run over 60 Tortoises. Or you cna get some inexpensive 1N4001 diodes and wire a string of them in series. Each one drops .7 volts. Connect to the 20V DV fixed terminals on the pack. Of course, this needs a string of 12 of them to get down to 12V - again, the simple DC wall wart is the easiest option.
Peter - I noticed a buzz as well. That was going to be one of my follow up questions. This is my first time working with these motors, wasn't sure if this was normal or not. What causes that exactly?
The fixed DC terminals on the MRC power packs are for hooking up one of their cab controls - which are the throttle and direction switch part of the power pack without the AC line voltage transformer. They take a fixed DC input and produce variable DC that can be used with cab control wiring to run a second train. The AC side is for powering twin coil switch machines and runnign things like structure lights, since light bulbs work fine on AC or DC.
If you go the route of adding series LEDs with the Tortoise motors for indications, you will reduce the voltage to the Tortoise motor by the LED voltage - for red and green this is about 2.7 volts. This is actually good - while the specs on the Tortoise say 12 volts, the sweet spot is really around 8-9 volts, they run quite a bit quieter at the lower voltage, yet still have plenty of power to move the points. So starting with 12 volts, and adding series LEDs to indicate position, leave the Tortoise with just over 9 volts, so you get indicator lights AND a better runnign Tortoise.
Yes, Elmer's picture is perfect. I'll link it in for everyone.
This shows a pair of 2-lead LEDs. They can be either single-color, in which case one will light for one direction and the other will light for the other direction, or they can be bi-polar, and there will be one green and one red, both always lit but with the colors changing with the direction of the turnout.
You can use the variable DC. I would suggest building a shelf beneath your layout for it, so the variable knob is not easily accessible. I prefer a sligthly lower voltage for my Tortoise machines, more like 8 or 9 volts, because it slows down the motion of the points.
The auxiliary contacts on the Tortoise are set up as two single-pole, double-throw (SPDT) toggles. This is the diagram from the Tortoise instructions, for reference:
These SPDT toggles are completely independent of the drive power on terminals 1 and 8. For powering frogs, connect a green wire (because use of consistent wiring color codes is a good idea, and frogs are green) to the center post of one SPDT (posts 4 or 5) and then a pair of track feeder wires from your bus to posts 2&3 or 7&8. I use a meter to get the pairing right, or you can clip them together and run an engine over the powered frog. If it shorts, reverse the feeders.
I did a test hook up with an old MRC Tech2 Railpower transformer to power Tortoises. Connected the Torti to the Variable DC and turned the throttle up to a measured 9 volts of output. It operated the Torti okay, but with the switch mach. emmitting a continous and much irritating buzz.
Went with Torti instruction sheet and used method 2, Bi-Polar DC with SPDT toggle switches and two 12vDC 3A desktop switching power Supply. Driving 24 torti, works great and no buzz.
regards, Peter