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Our yard occupies an entire small former bedroom and consists of 7 concentric reverse loops. There are six sidings plus the main. On the inbound leg, the tortoise wiring is straight forward as each siding connects directly with the main. However, on the outbound leg, four sidings converge into two, the resulting two converge, and that track is joined by each of the remaining two sidings before rejoining the main. My plan is to be able to engage each siding with just a single toggle switch. In other words, with just a single toggle the appropriate (multiple) tortoises will be set. I have a design, but it's complicated. I'm thinking some of you must have done something similar and hopefully simpler. Thanks in advance for any and all advice.
 

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there are several approaches depending on whether you are using snap switches or tortoise like switch machines

an approach uses diodes to direct a pulse to snap switches. however this requires a more beefy supply since power is routed to multiple coils at the same time

for tortoise machines, latching relays can be selected using diodes to change polarity or route +/- 12V to the switch machines
 

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Discussion Starter #4
We use tortoise switches.
Yes, diodes are a must.
I was not aware you could run through a switch if the spring was weak enough. The spring bars we have are quite stout. Will need to get some new ones and try it. Thanks.
 

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a latching relay has two coils. Power is applied to a coil to switch it's state which it holds after power is dropped from the coil

momentary switches can be added for each track and diodes connected between that switch and the appropriate coil for each turnout that needs to be switched. there will be multiple diodes to each relay coil unless there is only one connection.

not the least expensive approach.

dpdt relays are need is a single 12V supply is used and polarity must be reversed. spdt if both +12 and -12V supplies are used and simply routed
 

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Tortoise powered turnout points are held in place
by the motor, not springs, so the trains can't push
the rails aside.

If it's not too late, you could change the turnouts to
twin coil motors and use the very simple and easy to operate
Diode Matrix system. You push a panel button in any yard track and all turnouts in the route are set. Requires only
a barrier strip terminal board and a few diodes.

It's going to be quite complex to have the same sort of
system using Tortoise motors due to the fact they use
reversing polarity DC voltage.

Don
 

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Simple control for multiple Tortoise motors

Our yard occupies an entire small former bedroom and consists of 7 concentric reverse loops. There are six sidings plus the main. On the inbound leg, the tortoise wiring is straight forward as each siding connects directly with the main. However, on the outbound leg, four sidings converge into two, the resulting two converge, and that track is joined by each of the remaining two sidings before rejoining the main. My plan is to be able to engage each siding with just a single toggle switch. In other words, with just a single toggle the appropriate (multiple) tortoises will be set. I have a design, but it's complicated. I'm thinking some of you must have done something similar and hopefully simpler. Thanks in advance for any and all advice.


gordo53;

I use a very simple system I found in Model Railroader Magazine. The article appeared in the November 2000 issue.It's titled "Route Control for slow-motion turnout motors" by David K. Smith. This system is bone simple analog, no computer chips at all. It uses a center-tapped transformer, a few diodes and resistors, two capacitors, and one rotary switch. That's it! The photo below shows my control panel for Cedar Falls, WA. The right-hand, orange, part controls the turnouts. The white part on the left only controls the lights and motorized doors of the engine house above the panel.
The single rotary switch is simply set for whatever track you want, and all the turnouts are automatically set for that track. You can enlarge the photo by clicking on it. Two clicks gives a detailed view.

You can probably order a back issue, or download the article, from Model Railroader for a fee. [email protected] Or (800)-533-6644. I would send you a copy of the article, but, the article is copyrighted, which, legally, makes it a federal crime for me to send you a copy, and anyone, including federal law enforcement, can look in on this forum. :eek:

good luck, have fun;

Traction Fan :smilie_daumenpos:

Cedar Falls control panel.JPG
 

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Tortoise powered turnout points are held in place by the motor, not springs, so the trains can't push the rails aside.
If you use a light enough spring wire, they will open as you go through, I've seen it first hand. We have also done the same with the NJI switch machines.
 

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You can use Digitrax DS64's and program the routes in them. It's designed to the use one push button to set a route. Like most Digitrax products they are a marvel of versatility hence have complicated manuals. If you want to involve a computer you can use JMRI to control routes. Of course if your good at programming an Arduino, you can roll your own controller! Note that in use the DS64 does not need Loconet, but to set up the route programming you will need a DCC connection. Nice thing about DS64's is that they can be set up to use their own power supply and not use up track power like switch-its.
 

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Discussion Starter #10
I emailed a request for a copy of the November 2000 article. Couldn't download it (unless I have a digital membership). Thanks for the tip.
 

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Thanks Greg. Being a relative newbie, I didn't know the term "yard ladder". One of the examples in that piece is just about an exact match to what I'm working on. Looks like a simpler solution than mine which is a very good thing. I'm using toggle switches instead of a rotary, but the logic is the same. I had to chuckle. I was a software developer for 20 years. The "truth" tables were not unfamiliar.
 

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Toggle vs. rotary

Thanks Greg. Being a relative newbie, I didn't know the term "yard ladder". One of the examples in that piece is just about an exact match to what I'm working on. Looks like a simpler solution than mine which is a very good thing. I'm using toggle switches instead of a rotary, but the logic is the same. I had to chuckle. I was a software developer for 20 years. The "truth" tables were not unfamiliar.


gordo53;

The circuit recommended by gregc sounds like the same one I suggested. I'm glad he could furnish you with more information.
Using that circuit, the higher positive, "overriding " voltage is supposed to be applied to only one route at a time. With the specified rotary switch, this happens Automatically, since the switch can only supply power to one of its terminals at a time. With a group of toggle switches though, it's quite possible to have more than one switch "on" at a time, which would apply the higher overriding voltage to two, or more, routes simultaneously, possibly telling one Tortoise motor and gear train to rotate both clockwise and counter-clockwise, at the same time. I don't know whether that would damage your expensive Tortoise machines, or not, But I recommend using the rotary switch as an extra safeguard.
Obviously, you would not likely select both track 'A',and track 'D', at the same time intentionally, but accidents do happen, and I've learned that Murphy's law is very true, and worth providing insurance against.
Spring-loaded, momentary, toggle switches would seem like a possible solution, except that while pushing one to the "on" position will cause the circuit to work normally, the second you let go of it, things will go back the way they were. The circuit only works by feeding that overriding voltage to one route's motors, and keeping it there constantly. The rotary switch does this automatically too.

Traction Fan :smilie_daumenpos:
 

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not sure what you're getting at above. this design depends on the rotary switch to select only a single route and maintain voltage
 

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Agreed

not sure what you're getting at above. this design depends on the rotary switch to select only a single route and maintain voltage
gregc;

I know. That is what I was getting at. The OP said he wanted to use (presumably several) toggle switches instead of the single rotary switch. That can work, but it has the built-in potential for having two toggles "on" simultaneously and possibly telling a Tortoise motor to run both forward and reverse at the same time. Using the rotary switch, as designed, eliminates this possibility. So I'm recommending that he use the circuit as designed, with a single rotary switch, not an array of toggle switches.

Traction Fan :smilie_daumenpos:
 

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Toggle switches

i missed this.

not sure how you can use toggle switches for route selection.
gregc;

Not that I advocate this, I do not. However it could be done. Think of how the rotary switch in the original circuit operates. There is one common terminal which has the voltage that is used to select the route on it. By rotating the knob attached to the rotary switch you connect that common terminal to one of several output terminals ranged around the fiberglass disc of the rotary switch. In short, you connect the voltage to one terminal and keep that voltage constantly on that same terminal to operate the circuit as designed.

Now think of a row of SPST (on-off type) toggle switches, built into a control panel, with each switch set into a line representing each of the yard tracks.
If we feed the operating voltage to all the "input" terminals of all the toggle switches, then we can flip one toggle switch to its "on" position and feed the voltage to the output terminal of that switch, and keep it there. Electrically, this does the same thing as the rotary switch. However, it is absolutely dependent on the human operator. He has to flip only one toggle switch "on" at a time, and always remember to switch that toggle switch "off" before selecting a different track, by turning that track's switch "on."

While this is quite doable, you can probably see the potential for human error inherent in this arrangement. By contrast, a rotary switch's mechanical layout prevents you from even being able to select two routes at once. It will only allow voltage to be connected to one route's output terminal at a time.

regards;

Traction Fan :smilie_daumenpos:
 

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However, it is absolutely dependent on the human operator.
guaranteed to fail



momentary buttons could be used (again assuming ???) only one button is pressed at a time, and held until all motors have completed travel. The tortoise switch machine are likely to hold the point in position.
 

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Agree and disagree

guaranteed to fail



momentary buttons could be used (again assuming ???) only one button is pressed at a time, and held until all motors have completed travel. The tortoise switch machine are likely to hold the point in position.


gregc;

I agree with the idea that humans can, and sooner or later will, fail.

I disagree with the momentary pushbutton idea though. Even if the operator pushed one button, and held it down, (unlikely, at least consistently, every time, forevermore.) The second he let go the overriding voltage would be cut off, and the constant, lower voltage would drive the Tortoise back the other way.

Traction Fan :smilie_daumenpos:
 
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