Problems with ATLS Trigger


New member
Hi, I'm having a problem with the ATLS LCM Triggers see my setup below

when the train comes in from either direction (and either route) the crossing activates with trigger 1, ignores both triggers 2 and 3 and is disengaged with trigger 4


thanks - CG
Make sure they are all set for Advanced 4-Trigger mode. What I'm thinking is happening is 1 starts it and 2 would release it, were it not for the train then occupying 3 before 2 clears, thus still showing the crossing as "occupied" (as if the triggers were on a second track with a second train occupying) and then 4 finally clearing 3.
I agree with ctclark1, you should be better off by just deleting 2 and 3 triggers. so 1 would trigger and 4 would disengage or visa versa.
Not sure, then. I've set up over 120 ATLS crossings and linked intersections on three different routes in the last few years and never seen anything like that. Maybe something to do with overlapping radii on triggers 2 and 3? Beyond that I'm out of ideas.
it is worth noting that this controller also controls an intersection, see below
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Broken image, but I did notice the intersection in the original picture. Your crossings are fed by the special SPL phase, right? If so, I'm still kind of at a loss as to why this might be happening. If boat doesn't pop in here soon you might try PMing him, he'd have the best idea as to why this might be happening. I could write out how I might set the intersection up if I were doing it, but I'm not sure how you want the actual intersection to interact.
I think you may be getting confused. Front of train passes a trigger to activate and rear of train to reset. So train approaches T1 and activates, T2 ignored, Rear of train passes T3 and resets and T4 is ignored. The fact that 3 and 4 are fairly close together may look as if the reset is triggered on T4.The radius of 3 and 4 may overlap each other. I would put triggers 1 and 4 further away from the crossing and set T1 for priority 1 and 2 only so a train with priority 3 could use the branch line without triggering the crossing.
you were right stagecoach, I had the Triggers too close together so it lookt like it was 4 that was closing and not 3