I have completed handlaying a 90 degree crossing. I am looking to power both routes, with DCC. Besides the obvious cuts between the rails, what other gaps need to be cut? I have filled the flangeways with solder and cut them down with a saw to make a "casting" for the diamond => the guardrails are also hot. There are no PC board ties involved in this crossing.
What electronics will I need to make both routes live (I assume at least one autoreverser or frog juicer, if not more)?
You need to make sure that a wheel cannnot make contact with two rails of different phase at any time. Your "standard" gaps should take care of that but be careful with those hot guard rails and metal diamond.
As far as any extra electronics... none should be required. Of course that depends on where the track goes after the crossing. Assuming a figure 8 type plan, no extra electronics will be needed.
Martin Myers
Not that Martin requires affirmation (he's very savvy with DCC and other stuff...), but that's the way I see it as well. Depending on how wide your metal tires are, if any of them manage to bridge two hot rails across any one gap, you'll get at least a temporary spark/hesitation if the base short circuitry doesn't react first and cut power to your rails entirely. Normally, a crossing doesn't need anything more than what I hope you mean when you say the obvious gaps.
selectorNormally, a crossing doesn't need anything more than what I hope you mean when you say the obvious gaps.
The only gaps I have cut are between the rails (4 gaps). I have provided a crude sketch below. I guess my specific question is should I gap 2 corners (Frogs?) or all 4? Yes I am using +/- but the concept (not creating a short) should be the same across all types (DC/AC/DCC) of power. I figured +/- would be universally recognizable.
BMMECNYCWhat electronics will I need to make both routes live (I assume at least one autoreverser or frog juicer, if not more)?
have you seen this page:
http://www.dccwiki.com/Wiring_Crossings#Dead_Frog_Diamond_Crossing
greg - Philadelphia & Reading / Reading
gregc BMMECNYC What electronics will I need to make both routes live (I assume at least one autoreverser or frog juicer, if not more)? have you seen this page: http://www.dccwiki.com/Wiring_Crossings#Dead_Frog_Diamond_Crossing
BMMECNYC What electronics will I need to make both routes live (I assume at least one autoreverser or frog juicer, if not more)?
No. But that should be helpful. From what I gather I need only to gap 2 of the frogs (on opposite corners) and either provide an autoreverser or 2 frog juicers. The other two frogs can be hard wired. I already have an AR1 available to me so I will likely attempt to make use of that.
You need at least 4 more gaps in the rails on the outside of nthe crossing. The track running up and down in your drawing must have one rail positive and one negative for a train to run. They must also match across the crossing. Still no auto reverser is needed and it wouldn't fix the problem either.
i'm no expert, but is looks like only two of the frogs/corners require reversing. Each would need (2) gaps on the rails leading to the crossing, as well as (2) gaps inside the crossing
| | | | | | | | + + + - _+_| |_+_ _+_| |_-_ _-__ __-_ _+__ __-_ | | | | - - + - | | | |
mfm37 You need at least 4 more gaps in the rails on the outside of nthe crossing. The track running up and down in your drawing must have one rail positive and one negative for a train to run. They must also match across the crossing. Still no auto reverser is needed and it wouldn't fix the problem either. Martin Myers
Martin,
I never had any intention to wire the crossing per the first drawing. I was illustrating the problem I had (the entire crossing is metal), with no plastic parts in it at all. My intention is to have all parts live at all times. In order to do this my understanding was that I needed some sort of reversing circuit (or switch I guess would work as well).
I modified drawing to show where I think the AR connections should be. Edit: Corrected draw to show correct wiring. Martin Please explain why you think this will work with no AutoReverser/frog juicer, and why you dont think either of those items will make this work.
Makes sense now. Autoreverser should connect to the red and blue sections. One output wire to each. That should allow a train using either route to go through.
mfm37Makes sense now. Autoreverser should connect to the red and blue sections. One output wire to each. That should allow a train using either route to go through.
I don't understand and I was hoping someone knowledgeable than me would respond to the auto reverser question. The AR both detects and reverses, would it detect if connected to the red and blue?
Henry
COB Potomac & Northern
Shenandoah Valley
the AR supplies current to the red and blue frogs. As a train enters the crossing, a metal wheel will bridge one of the gaps and creates a short. The AR will detect excessive current flowing through the connection to the frog. It then momentarily drops power, reverses the polarity to the frogs and restores power which should be cleared.
Thanks Greg