Automatic Turnout Operation : LUSENET : Wiring for DCC : One Thread

I haven't seen it anywhere, but has there been a design for Automatic Turnout Operation. By this I mean a system where the turnout throws when a train approaches from either of the frog end tracks. It would need to use occupancy detection and then operation of the turnout. In my layout there are a number of turnouts only approached from the frog end, so there is no need for operator control. It would avoid derailments.

-- Eric Dickens (, December 31, 2003


Yes. See recent answer regarding automatic turnouts for reversing loop. I've not seen any commercial products to do this but I have it working with both Tortoise slow motion and Atlas dual coil switch machines on my HO scale home layout.

-- Don Vollrath (, December 31, 2003.

I have posted a file in the Yahoo mrrelectronics forum regarding this topic.

-- Don Vollrath (, January 05, 2004.

Thanks for that. But if I use a computer to automate the layout, then it may be easier and cheaper to use block occupancy detection and accessory decoders.

There is another problem with DCC and that is, what happens if a train approaches the other arm of the turnout before the first train has finished crossing? Some form of interlock to stop the second train needs to be incorporated.

-- Eric Dickens (, January 06, 2004.

Yep. Two trains at the same place at the same time are always a problem. You didn't say anything in your original inquiry about interlocking. Making a train that is too long run around a reversing loop that is too short can cause a loco to crash into its own caboose. Making it fully fool-proof, even with real engineers driving the trains, is not necessarily simple or easy. At least DCC has an E-Stop button.

-- Don Vollrath (, January 08, 2004.

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