Inconsistent operation of multiple track ATLS grade xings


Hello all,

I have been installing grade crossing signals utilizing the ATLS system on a certain route, and I've noticed some glitchy and inconsistent operation when more than one track is involved. Most of the route is double-track main, thus a majority of the crossings are double track, some three or four with sidings involved. When doing a trial run tonight, about half of the crossings are not working as expected. I have them all set up on 4 trigger mode. Some do not activate until the train reaches the "island" circuit (trigger directly adjacent to the road for 4 trigger setup), thus ignoring the "activation" trigger. Some activate as expected, but clear as soon as the end of the train reaches the same activation trigger, with the train still fouling the crossing.

At least one activated and cleared as expected, but re-activated as the train cleared the activation trigger in the opposite direction. With 2 or 3 tracks, this involves 8 or 12 triggers, respectively. I have checked to verify that they are set to the proper channel. There was no stopping or backing up involved; I kept the train at track speed. I do have the activation triggers set to ignore train priority 3, so I can roll up close to crossings without activating during switching. I was running in priority 1 for the trial run.

Anybody have any ideas as to what might be causing this? It obviously has to do with having multiple track crossings, as it never does this to me with single track. Most of my triggers were set for 30-40 MPH running, and my activation triggers were placed roughly 1500 feet from the crossings, with island triggers directly at the edges of the roads. Any insight is appreciated.
This can happen even if you have a lot of experience with ATLS. Check every trigger is set the same, not just the channel (it only needs one to be different to cause a problem) and make sure that the train does not exceed passing 4 triggers. I am guessing you have placed some triggers after a junction and the radius of the trigger is seeing the train before the junction is set for the right direction. If this is the case, when the junction changes, the trigger on that track is seeing the train as well and the ATLS is counting this as the first trigger. Make sure the trigger is far enough past the junction with a smaller radius so as not to see the train before it reaches the junction.
Thanks for the reply. This issue is not related to multiple tracks as I had thought... I have now seen this happening on single track with absolutely no switches or other tracks nearby. I have checked to ensure that all triggers are set the same, which they are. I'm curious, what exactly do you mean by making sure the train does not exceed passing 4 triggers? There are some crossings that are extremely close to each other, with long trains occupying both at once, that is 8 triggers, sometimes even more with multiple crossings in succession. Example diagram below, red X's indicate crossings and yellow lines indicate triggers...


After some more checking, I have pinpointed two different behaviors... Crossings will either deactivate as the rear of the train clears the first trigger, with the train still occupying the crossing, or they will simply not deactivate at all. Is it possible that the triggers are conflicting with each other, even though they are on separate and unique channels?
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You might be right. They could be overlapping and getting confused as the train triggers one then the other like at the deactivate #1 activate #2 combo.

I will do some more troubleshooting tomorrow and post back... will try a few things to see if I can get to the bottom of it.
Hi D0g,

Triggers on different channels should not conflict. You say you have double checked the channel and mode of each trigger.....

Do you have the latest versions of the Trigger and Controller? Sometimes Trainz can send extra, spurious 'Enter' messages which confuse things. The latest ATLS versions try to catch that but you may have found a situation where there is a problem.
As I mentioned in my PM, if you would like to e-mail a cdp of your route and session, I will take a look.

Don't know how close each crossing is to each other in order to work out how close the triggers are between them. When I said max 4 triggers, this refers to the max number of triggers to pass on a single channel. Channels wont conflict with each other and the triggers can overlap each other C1,C1,C1,C2,C1,C2,C2,C2. One other thought is that when you placed the triggers on the crossings (depending on the crossings used) you may have a trigger placed on an incorrect track if you use a grade crossing other than an ATLS one. This means the train passes an incorrect number of triggers. If using a non ATLS crossing raise the track over the crossing to see if the triggers move with the track, if not the trigger is on the grade crossing track and not on the actual track the train is on.
Hi D0g,

As I mentioned in my PM, if you would like to e-mail a cdp of your route and session, I will take a look.


The route, Donner Pass, is payware, so unfortunately I don't think I can do that. I have tried to create a small route with some duplicates of issue crossings I have encountered, but for the life of me I cannot duplicate the issues outside of Donner. I will make sure the latest versions of trigger and controller are installed...

Thanks, all, for the replies.
Okay... I downloaded the latest versions of the assets. I had versions 2.5 instead of 2.6. I am not having the issues as before, they appear to have been fixed with this update.

The only side-effect now is that some crossings are clearing a little soon, while the train is still in the "island" circuit between the two clearing triggers. I'm assuming the incorrect trigger (2nd in sequence instead of 3rd) is clearing? Pic below shows this in action... Notice the rear of the boxcar is still in the crossing, yet the gates are a little above horizontal and have started rising. I have the triggers placed directly behind the crossing signal towers.

This is not a huge deal, though. Certainly better than it was before. Thanks, everyone, for the help! :)
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That's good news. :)

You might be able to adjust the timing of the gates which will help with your problem.

Set the triggers radius to 1.00 m. They default to 20 meters, should fix the early gate up situation.
This would make the gates open even earlier. The first trigger activates the gates when the engine arrives in the radius and the third deactivates when the last wagon has passed the radius. second and fourth don't react.