Hello Secound post here. I have been getting back into trains, and I have a DCC question maybe some one here can answer. Is it possible to have a DCC add on or the like, to realistically control a grade crossing with a road? I know it would require detection. I have the flowing DCC items. Super Chief Extra. Se8c Pr3 I know I will either need to get a BDL168 Or pick up 2 BD4’s ( I’ll probably go with the BD4 seeing that I Already have a SE8c). Probably a few slomo Switch machines for the gates. Also Multiple tracks is a must. What else is needed to do this? Thanks Tom
I have thought about this a little but it will be a looooong time before I get to where you are. I would think you could isolate a block that has the grade crossing in the middle; you already listed the block detection boards you would need. I think you could take the inputs of the block detection boards and drive an output to the turnout (gate) motors and signals via something like an SE8C? Hmmmmmm... (scratches head) Jamie
A DS64 will drive the turnout motors for the gates and light crossbucks to. You'll need the detection boards. DS64 has sensor inputs built in.
The number of detectors needed will be dependent on the number of tracks and whether they will be operating omni-directional or bi-directional. For running in a single direction, each track will require one block detector across the strike in point and departure point of the crossing. If bi-directional, then three detectors per track, one for each strike in block either side of the crossing and one over the crossing itself. Then there's circuitry to determine which direction the train is travelling in so the opposite direction strike in block is ignored. The operation of the gates is straight forward, comparatively. Could be quite interesting sorting out the operation if bi-directional, though.
Given any thought to hooking up a computer to your layout? Altogether, it might end up being easier to use JMRI to program the behavior of the grade crossing than anything else, especially if you are going to have more than one. And then you can use it for other stuff on your layout too, such as signals. Just food for thought... Incidentally, you should be able to control both/all the gates for one crossing with one tortoise switch machine. Just a matter of creating the right lever system.
I would consider using Memory wire for slow realistic grade crossing animation. Also, check out Paco's site for cheap DIY decoders. http://www.tinet.cat/~fmco/home_en.htm
It sounds that you have everything you need to this point,but based on what you said you need a DS64 it has a grade crossing feature built into it by just reassigning the opt switches. I 'm not sure but you may be able to control up to 4 of them. ~AlanC.
This is another method. I personally use the signal animators and I am very pleased with them . Although not DCC controlled. Logic Rail Technologies home page
Dang I have been meaning to post to this thread for several days and keep forgetting. Anyway, in the issue of Model Railroad Planning 2010, Bill Darnaby has an article describing how he has implemented electronics for signaling, junctions and grade crossings. He has a great detailed example showing how to use three detection sections of a Digitrax BDL168 block detection board and outputs of a Digitrax DS64 stationary decoder to automatically control grade crossings. In his implementation, trains will trigger the crossing flashers as they approach the crossing but the flashers will turn off if the train does not reach the crossing during a predetermined time interval, say 20 seconds. The flashers will then turn on again if the train actually reaches the crossing. This is almost exactly how prototype grade crossing flashers work and is the method I am using for my first grade crossing that is currently uner construction. It seems costly to use three detection sections of a BDL168 to control a grade crossing, but the prototypical operation makes it worthwhile to me. I will post updates as I make progress, but it could be a while as I am waiting on decals so I can finish the road that the crossing flashers will be there to protect! Jamie
I certainly don't know how to do this, but I thought this Belmont Shore concept was a clever idea to make a road crossing with no gates. The scene is viewed form an aisle. When a train passes the crossing buck lights flash and the auto brake lights come on. The stopped auto lights are accomplished using fiber optics. Heck, you can probably used LEDs these days. Anyway, that saves the operation of crossing gates.
