Original page created on 10/07/2012; updated on 15/12/2023..
What to automate?
Introduction
As I said elsewhere, I don’t have a layout, but only a removable circuit. It’s a dog bone layout, and therefore it has a false double track. It has also a turning loop and a bundle of lanes allowing storage of trains of up to 3 m long (nine modern coaches). The layout is about 21 m long.
My circuit works in digital. But I don’t see the advantage of controlling the turnouts or the signals in digital, except of course the wiring simplification. The decoders are expensive, and I want to be able to control the turnouts with each button, not with addresses typed on my remote control. Note that the digital control with buttons is possible, see for example Paco’s Official Web Site and its XbusTCO, but you have to put your hands in the sludge, as my father said…
Synoptic
Here is the synoptic of the storage area that I wanted to automate with regard to the routes. I want to be able to control a route, including the exit turnouts, because the Peco Electrofrog devices I have chosen are not trailable, under penalty of short circuit: their frog is fed according to the position of the blades. But I also want to be able to control each turnout individually.
We see that there are seven turnouts, marked A to G. Each position is marked by a LED, green in direct position, red in diverging position. Yellow LEDs grouped in series marked L1 to L7 materialize the tracks and are supposed to light up according to the requested route.
Routes
The train, marching left hand as it should be, comes from the bottom right by track 2. The normal route, which I have designated by VOIE 1, passes through track 1. The second route, VOIE 3, passes through track 3. The third route, VOIE 5, passes through track 5, you would have guessed. There is a BOUCLE (loop) route which allows a train to take the track 4, then the turning loop through the turnouts E, B, C and D. The train is thus in opposite direction on track 2. But one can also get this train arriving normally via track 2, then make it take the loop to bring it on track 4. The BOUCLE route also activates a rail polarity reversing relay. Finally, there is a route (a big word here) TIROIR which merely positions the turnout A on the track 4 and the turnout E on the dead-end track.
Note that I don’t have the ambition to make a flexible transit system, where it would be possible to program several successive routes which would gradually take place as and when required. For example, if a train A is expected Track 3, while another, B, is at departure on Track 5, we must request the route VOIE 3 to receive the train A, then, when it has arrived, ask for VOIE 5 for letting the train B go. Hence, the advantage of being able to individually control the turnouts. In the example I can ask for VOIE 3 and then put the turnout G in the diverging position to let the train B go while the train A is already engaged on Track 3. But we must not forget to put G in position for the departure of train A!
Note: if you think there is an error in the LEDs of the turnout G, think again. I was obliged to represent this turnout upside down to simplify the synoptic, but in fact it is a curved turnout, as elsewhere A and F.