Uk 2 Aspect Repeater Signals And Aws

Consider the following scenario....

You are travelling along and you are about to come onto a section of track with 3 aspect signalling. Of course, the very first signal cannot have a red aspect as there is no advance warning of it being red and so you need some form of "distant".

I believe this is often done with a 2 aspect "distant", so you get:

Signal 1: 2A "distant" (YELLOW/GREEN)
Signal 2: 3A (RED/YELLOW/GREEN)
Signal 3: 3A (RED/YELLOW/GREEN)
Etc. Etc.

So, I've signalled this, and I always get incorrect AWS behaviour for Signal 1 in the case where Signal 3 is RED and thus, Signal 2 is YELLOW. Signal 1 correctly shows GREEN but the AWS caution is triggered, which I have to cancel to avoid an emergency application.

I think because this is because the AWS ramps look for the next "stop" signal ahead and behave accordingly. In this case the next stop signal is Signal 2 and it's showing caution so the AWS responds with a caution which is incorrect. Signal 1 is showing green and so the AWS ramp should give a clear bell.

Is there anyway of getting the correct behaviour here? (I've gotten the same behaviour with both UK Pro and JTMS signals....)

 

There is nothing wrong with the behaviour of the signals or the AWS
Did you put the correct ramp in the right position and was the track object facing the correct way?

 

How can you possibly say there's nothing wrong with it? It's clearly broken!

JTMS AWS Ramp, pointing towards;
JTMS Repeater B2A YG (Signal 1)
JTMS AWS Ramp, pointing towards;
JTMS B3A 1T (Signal 2)
JTMS AWS Ramp, pointing towards;
JTMS B3A 2T F1 (Signal 3)

All are laid out correctly, with arrows pointing the correct way.

The diverging route beyond signal 3 is set, and so the approach control is holding it at RED. Signal 2 is therefore correctly ay yellow, and Signal 1 is correctly showing green (since signal 2 is OFF). Thus the AWS ramp for signal 1 should give a bell for clear. It doesn't. It gives a warning.

This behaviour is incorrect

(Also incorrect is the complete lack of overlaps in train simulator. Then the approach control is incorrect too. It's usually done by time, not location - since the idea is to control the speed of the train. Usually the train has to occupy the berth track circuit for a given time before the signal is released).

 

Not correct - Signals routeing thru a Slower Speed Crossing did not clear until the train occupied the track circuit before the signal.
What we drivers used to call "Track Circuit Approach" .
I knew at signals where it Should clear as you approached as you went on to the next TC
It was irrespective of speed.

Signal 1 - the Distant - where is the Direction controller for the Magnet before, next to or after?

 

With respect to the marker for the AWS magnet. It doesn't matter whether you put it before, on top of or after the magnet (so long as it's the right side of signal 1), the behaviour is always WRONG.

https://sites.google.com/a/railsimd...l-scripting#TOC-Automatic-Warning-System-AWS-

So the question is, is it the AWS ramp that's buggy, or signal 1?

With respect to your other comments:

Of course it's possible to release a signal when it hits a given track circuit. The problem with that is that it doesn't give you very good approach control in terms of speed. An improvement on this that once the train hits a given track circuit some form of timer can be used to ensure the train is slowed before the signal is released. Approach control can be further improved by the use of ATP systems and speed approach control - on such systems the driver doesn't even need to be aware he's taking a diverging route (of course he may wish to know when he's been given the WRONG route). We engineers can employ all sorts of tricks to control what you drivers do!

It's very easy to make assumptions on how a system works. For example, consider these two approach release systems:

System A

Releases the junction signal as soon as train hits a given track circuit.

System B

Releases the junction signal as soon as train hits a given track circuit *and* a given period of time has elapsed since it entered the previous track circuit.

So long as a driver followed the signals correctly, he would be unable to tell the difference between the two, because his actions ensured that whether it was system A or system B, the signal would always release on hitting the given track circuit. The only way he'd be able to tell through his own actions would be to ignore the signal aspects. That could result in a derailment due to excessive speed through the junction - so it's not recommended behaviour.

Railways are safe because the engineered systems the drivers are immersed in make the driver (or the train autonomously) do the right thing. For safe railway operation you do not need a driver. But you do need engineers. (With apologies to people in the US where that statement may be confusing.... ;o))

 

Just to confirm, it's the JTMS 2A repeater that's the problem. I get the correct behaviour if I use the 2A repeater that comes with London - Gillingham (which I think is the UK Pro signals)......

So that's another bug found. Sigh.

PS I think the JTMS CL signals have the wrong shade for the GREEN aspects. It looks TOO green to me......

 

I have had problems in the past with Just Train Signals - and Yes, the Green is the wrong shade

 

Hmmmm. After a bit of playing, I got the broken AWS behaviour with the Pro 2A repeater. Replaced it with a JTMS 2A repeater and it works again! Looks like there's actually a bug in how they link together and possibly even the order in which you lay them.

(I've got a very simple test route with a bit of track, 1 junction and 3 signals so I can play around!)

 

"Signal 1 correctly shows GREEN but the AWS caution is triggered"

Ahhhh... Do you wish to report a "Right side failure???"

Eric