I am running MTH DCS with the Z4000 transformer and a TIU, controlling the engine with the handheld. I am using Atlas track. I have 15 switches on the layout and they are all controlled with a tortoise. I am in the process of making a board to control the switches. The inner loop of my layout has a reversing loop on each end. I desire to make these reversing loops automatic, i.e. once the last car clears the switch, the switch will automatically throw so not to derail the train. I have done quite a bit of reading on different products out there but all seem to involve polarity switching, which I don't think I need. I envision needing 2 photocells, each on the track just after the switch, which are hooked up to a circuit. Once the train enters the reversing loop the first photocell goes dark as the engine and rest of the cars cover it. After the last car clears and the photocell sees light, the circuit tells the tortoise to move so the train doesn't derail. Can anyone shed some light on what product I could buy to do this? Any help is greatly appreciated as I have exhausted google trying to find someone with a similar setup. Thanks!
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Magnets and reed switches.
How would I wire that to a tortoise?
Why couldn't you use an insulated track section to set the switch as the train approaches ? It used to be built into Lionel postwar type switches.
Here's a nice solution. You can ignore the polarity part of the system if you're using 3-rail, but the turnout throwing portion is what you're looking for.
http://www.azatrax.com/reverse-loop-system-2.html
Matt,
That looks to be what I am looking for. I guess I can mess around with it as far as not hooking up the polarity switching. Thanks!
Tortoise can be made non-derailing if you can get a long enough insulated section to work with.
Sort of goes like this.... A relay is wired like an HO reversing switch (dpdt relay) which controls the tortoise ( connection 1&8), The insulated section controls the relay. . When the insulated section is unoccupied the switch is set normal for the straight, When the insulated section is occupied the dc reverses the relay contacts and the switch lines for the diverging route.
A train comes along at the switch point end and goes straight and then goes around the loop, enters the insulated section and the switch reverses. After the train has left the loop the switch returns to normal by itself.
You need a Bridge rectifier, a DC relay plus a long enough insulated section. I had one hook up at my other layout. worked pretty well. Downside, you can't leave cars on the insulated section else the switch reverses.
You do realize Tortoise switch machines are spring loaded points you don't have to switch them.At least that is they work for me.
I am a conventional operator. Here is how I would approach the problem. It assumes only 1 train is run on the loop and that the switch machine has an internal limit switch and can take continuous power. It uses a twin coiled latch relay and 3 insulated rails. Here is a suitable relay.
The relay throws the 2 machines wired in tandem. When the train is on the straight section (and crosses the outside insulated rail),the relay contacts throw the machines in the approach direction. When the train is on the reverse loop,the relay throws the machines in the opposite exit direction. The outside insulated rail sections need only be 1 section long. It is shown hooked to a Z4000 but could be used with any transformer with an accessory tap. The insulated rails have to be far enough away so they are not thrown when the train is on the turnout. The 10 volt accessory tap is run through a diode and provides half wave DC,charged to 14VDC peak by 2 capacitors,one to each coil. 220uf 35V should work. Click on photo to enlarge. From the description I surmise this is the layout with a reverse loop at each end.
The circuit would cost less than $10 to construct.
Dale H
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Gregg and Dale,
Thanks for the responses. I will have to give those suggestions some thought. May be a little beyond my abilities, haha.....
Assumption from post #1 is that this is Two Rail.
Mike,
I am using 3 rail atlas track. Sorry for any confusion.
The circuit I described previously could be used for 2 rail by adding reed switches and magnets.
Dale H
kevdd2,
You can use the Atlas non-derail circuit board 6924. Wire each switch motor that you want to use for controlling the reverse loop. The #6924 will throw the tortoise machines with no problem by using a section of insulated rail at each entrance to the switch. Just be sure to make the insulated rail section far enough ahead of the switch to allow it to operate fully before the train reaches it. If you visited the Atlas booth in York the display layout uses two of the #6924 circuit boards to control each of the two reverse loops. You can contact me at srhorvath@atlasrr.com and I will be happy to help you.
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Basic non-derail function would automatically move the switch, enhanced through the 6924 board that Steve mentioned. Click on the follow Atlas website links/wiring diagrams.
A lot of information on the Atlas site.
Typical non-derail with an ASC 3000 switch controller.
Typical non-derail with an MTH AIU.
Using Tortoise Switch machines with the Atlas Universal Switch Control Board (USCB).
Once you wire the first 6924 relay board the rest are easy.
Note that the 6924 relay board will control a cross-over pair of switches.
As Clem mentioned the Atlas switches are also spring loaded, non-derail, but on my original install they worked 95% of the time, still causing a few de-rails. Electric non-de-rail is the way to go, IMO. I've done some non-derail with Ross switches and DZ 1000 switch motors, again a plus to the operation. Ross also has the non-derail diagrams available with their switches.
These DZ 1000 switch motors/Ross switches are wired for automatic non-derail switching. Click on the triangle to access a Photobucket video. Rich Yoder GE 44 tonner that has been upgrade to ERR TMCC and sound.