TRAIN SLOW DOWN ?

CHIP2

New member
Hi ALL
Can some one tell why all my loco,s slow down at one point in my layout i have all the signals in & speed signs set at 100kph
for now just to get it going & i,ll change them speed when i get it working ok . I m just running one train for now & try & fix it.
Iv made layout before but it has not done this before & i can,t seem to work it out if anybody would like to chat with me on
skype would help a lot & is name on that is chip2toke if you need any more info. from me i can send it thanks a lot guys .


DAVE in AUST. THANKS AGAIN
 
I don't do Skype, but I have a couple of questions. How much does it slow down and for how long? Is this an AI train or are you driving? I have noticed (though I've never really tested it) that an AI train sometimes seems to slow down after a "Navigate/Drive Via" command. It doesn't actually stop, but seems to coast as if it went from drive to neutral. I "think" this is because AI trying to verify that all the junctions are set correctly, no other trains are on the track, etc. before it executes the next command. As I said, I've never really tested this and if I'm wrong I hope someone with more understanding will correct me.
 
I don't do Skype, but I have a couple of questions. How much does it slow down and for how long? Is this an AI train or are you driving? I have noticed (though I've never really tested it) that an AI train sometimes seems to slow down after a "Navigate/Drive Via" command. It doesn't actually stop, but seems to coast as if it went from drive to neutral. I "think" this is because AI trying to verify that all the junctions are set correctly, no other trains are on the track, etc. before it executes the next command. As I said, I've never really tested this and if I'm wrong I hope someone with more understanding will correct me.

Rick,

Your observation is correct. It's as though they've completed this task and are now loading the rest of them in.

CHIP,

There are some things to check.

1) The driver has his route set for him - the junction levers are set in his favor.
2) The route is properly signalled. If there are no signals, he'll only run at 64kph instead of 100kph by default.
3) If there are any slow points on his route, the driver will run at his slowest speed the whole length even if the slow point is 3km away.
4) Check your signalling. You need to have advanced warning or permissive signals before junctions with single track. If not the driver will drive at a slower speed for that signal.
John
 
So, in your point 3, why the train has to slow 3 Km ahead? I have the same problem, and it has been mentioned here several times. A bug?, and if so, will it be noted and fixed in the next SP-1...?
 
Some of this is actually related to the acceleration/decceleration of the train. A train with poor braking/decceleration will usually slow earlier (it may be the other way round though)

Also, if you're using Navigate To Trackmark, try using Navigate Via Trackmark instead.

Shane
 
Hi

I have just had a similar problem when creating a session on the GCR v2 route. When using a Navigate via command, all northbound trains would slow down to less than 10 mph through Ruddington station even though all junctions and signals were set in their favour. I tried various ideas without success until I used a path set rule to set a path through the station coupled with an autodrive command which seems to have solved the problem. Despite spending a significant amount of time on this issue I have no idea why Navigate via refused to work correctly. Perhaps the OP could try a using a setpath rule to see if it helps him with the problem?

Regards

Brian
 
Brian,

Are you using CAB mode? The drivers will slow down when they go through a station while in CAB mode. This doesn't happen with DCC mode. I'm not sure if it's a bug where the station scripts have taken control over the consist.

John
 
Hi

I have just had a similar problem when creating a session on the GCR v2 route. When using a Navigate via command, all northbound trains would slow down to less than 10 mph through Ruddington station even though all junctions and signals were set in their favour. I tried various ideas without success until I used a path set rule to set a path through the station coupled with an autodrive command which seems to have solved the problem. Despite spending a significant amount of time on this issue I have no idea why Navigate via refused to work correctly. Perhaps the OP could try a using a setpath rule to see if it helps him with the problem?

Regards

Brian

In my experience this behaviour is caused by an object of "kind buidable" situated between the train, and the drive-via trackmark. It appears to be caused by a flaw in the "drive via" code, as if the code cannot see beyond the object until it passes it. This can be tested by using a "drive to trackmark" command instead. If the trackmark is located far enough ahead of the buildable object, no slowing down will happen. These "buildable" objects include things like stations, AJS junctions and industries.
I have compared the codes for both commands, but I cannot find any significant differences except for the built in library functions they call.
Andyz
 
Hi John and Andyz

My interest is in railway operations so I never drive trains myself but use all AI trains. The stations on this route aren't interactive but there are some AJS junctions on it, including at Ruddington. I tried various things including adding new trackmarks in different places and moving existing trackmarks about but the only thing that worked was to resort to path setting. I would have to agree with you that there appears to be an issue with the Navigate via command.

Regards

Brian
 
From my experience the most common reasons for AI driver to run train at a lower speed than allowed are:

1/ The next signal is showing red. The driver will usually drive at half of speed allowed or 20 mph, whichever is greater. It does not matter how far the next signal is located. If it is located in distance of 10 miles, the train will drive slowly for the entire length. Remedy: If signals are located far away, use a distant signal 1/2 mile or 5/8 mile before the main signal (depending on the breaking distance). At an exit from a station with many turnouts, place an extra signal on the main line, some 1/2 mile after the last turnout. This signal, together with the following distant signal are likely to make your trains drive at the maximum speed permissible.

2/ The AI driver sometimes "sees" a speed limit sign ahead and they will slow down to make sure that they pass the signal with the right speed. This usually isn't a problem, except when driving on a high speed line (100 mph or faster). I found that in such condition AI driver cannot calculate the correct moment when to break and precautionary it drives slowly for miles. I don't know how to fix this problem other than redesign the track layout or lower the speed limit.

3/ Some platforms cause AI driver to slow down, but for a short time only.

4/ If you save driver session while AI train is picking up or setting down passengers, it is likely that after loading this session the train will drive at very low speed (20 mph I think). The solution is to drive the train manually to the nearest portal (if there is any) from which AI driver should be able to return with the normal speed.
 
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