Diamond crossover rule help needed

Midland

Sphenodon Punctatus
I can find no readme or instructions or information on how to use this rule.

Any help at all would be very much appreciated.






Cheers

Nix
 
Screenshots would be the ideal way to answer this but as I have no way of posting images, I will attempt a text description :)

Simplest case scenario: two intersecting single line tracks (no junction between them).

Track 1: Designate this the North-South Track and place two signals on this track, one on each side of the diamond crossing. Both signals are facing traffic that will be approaching the intersection - i.e. they are placed "back-to-back" on opposite sides of the intersection. Each approach must be signalled even if no trains will be coming from one of the directions. Name one signal DmdNorth (short for "Diamond North") and the other DmdSouth. The exact names used are not critical but they will need names for the Diamond Rule. Invisible signals can be used.

Track 2: Designate this the East-West Track and place two signals on this track, one on each side of the diamond crossing facing the traffic that will be approaching the intersection. Name one signal DmdEast and the other DmdWest.

Add Diamond Crossover rule to your layout and Edit its properties as listed below.

Select The first available Diamond Crossing Signal Group - you can have up to 8 diamond crossing groups controlled by this rule - I do not know if you can add a second rule to control more!!!

Identify the north signal (DmdNorth in example above), the south signal (DmdSouth), the east signal (DmdEast) and the west signal (DmdWest)

The principle is essentially the same (but with more signals) for intersecting double lines and I have used it for double track junctions to provide protection for the two crossing tracks. Here one of the signals in each pair will be invisible signals.

The limitation of the rule is that only 8 diamond crossings can be created this way - until I started writing this post I had not thought to see if a second diamond rule could be added.

Peter Ware
 
Thanks Peter, believe it or not that is perfectly clear and understandable.

I can see why I was having problems.






Cheers

Nix
 
Okay, here are some pics to show how I have set it up and how it is operating (or not!) for me...



http://img148.imageshack.us/img148/2985/diamond1fj1.jpg

This is an American double line, right hand running, with a junction. North is to the top (where the SP Trainmaster is standing) and south is the bottom. To the south just out of the picture are the points for the junction. The north bound track has a signal to show a diverging or normal direction. I have placed an invisible signal (blue and grey) just onto the branching track and called it "east". There is another invisible signal facing the opposite direction just past the diamond called "west". On the southbound track on which the Trainmaster sits the signal directly in front of the Trainmaster is "north" and just past the diamond is an invisible signal facing the opposite direction called "south". As far as I can work out the four signals are set up in the manner required by the rule and are placed in group 1 in accordance with their names. So let's try it out...




http://img403.imageshack.us/img403/7125/diamond2wu9.jpg

Here X1780 sits before signal "north" and beyond that both points are normal; hence the green signal. In the distance you can see an approaching steam train which is schheduled to turn left at the junction and head across the bows of X1780.




http://img247.imageshack.us/img247/1089/diamond3vj5.jpg

The opposing train reaches its trackmark and the points reverse. Signal "north" in front of X1780 goes to red in accordance with the rule. Everything appears correct but do remember that the steam loco has not yet reached signal "east" which is an invisible signal.




http://img46.imageshack.us/img46/3023/diamond4wq4.jpg

Whoah! As the Big Boy straddles the crossover the rule seems to let go. X1780 gets a clear proceed on signal "north" and the original TRS problem is back in all its glory! What to do? What to do?







Cheers

Nix
 
Last edited by a moderator:
Nix
Search this forum for a thread called "Diamond Track Crossings", this may be of interest to you.
andyz
 
I had the same issue. What I finally did was use the "Junction Controller V2" found on the DL station.

Set a rule in the controller so that if the East junction is set for the diamond crossing, the West junction is set for the track not going thru the diamond. Then, set another rule so that when the West junction is set for the diamond, the East junction is not. This set up will not allow both junctions to be set for the tracks crossing the diamond at the same time.

In the case of your 3rd & 4th pics, the junction on the right would be set to the track going off to the right and keeping the signal in the forground at red. When, the steam train clears the left junction, the right junction can then be set for the track crossing the diamond (which will move the left junction to the track crosing the diamond), allowing a green signal to be displayed for the train in the forground.

By the way, my set up didn't use the invisible signals that yours did. However, I did use bi-directional signalling. See below:

J1 = East junction
J2 = West junction
S = signal
<, >, V = direction a signal faces.

PHP:
-------<S---J1----S>-------
-------<S--/--J2--S>-------
          /  /
         S  S
        V  V
       /  /
      /  /
 
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