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| Wrong signal aspects in the carmuirs area 04/04/2010 at 15:18 #1058 | |
sparplu
18 posts |
I don't know if this has been reported but CW13 becomes double yellow if the route is set up at CEJ3 before the train arrives at the signal. CEJ3 is not approach released green signal if the route is set up towards Falkirk the green signal is shown (and can been seen while the train is passing CW12) as soon as the route is available. GH4 is an approach released Junction signal for trains going down the branch to Fouldubs. Also at Garnqueen North Jct you get a single flashing yellow at CN354 for trains going towards Springburn. Also CN352 produces a double yellow for trains going towards Motherwell as MG906 protects acrossing and only get the green if Motherwell box have set the crossing up in time. These are all observations from what actually goes on as a driver over this area. Log in to reply |
| Wrong signal aspects in the carmuirs area 04/04/2010 at 15:18 #8170 | |
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sparplu
18 posts |
I don't know if this has been reported but CW13 becomes double yellow if the route is set up at CEJ3 before the train arrives at the signal. CEJ3 is not approach released green signal if the route is set up towards Falkirk the green signal is shown (and can been seen while the train is passing CW12) as soon as the route is available. GH4 is an approach released Junction signal for trains going down the branch to Fouldubs. Also at Garnqueen North Jct you get a single flashing yellow at CN354 for trains going towards Springburn. Also CN352 produces a double yellow for trains going towards Motherwell as MG906 protects acrossing and only get the green if Motherwell box have set the crossing up in time. These are all observations from what actually goes on as a driver over this area. Log in to reply |
| Wrong signal aspects in the carmuirs area 04/04/2010 at 20:04 #8181 | |
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bill_gensheet
1318 posts |
Many thanks for your notes, referred to sim author to check the plans for these functions. Please confirm for us what you see at CW13, as that appears to follow the plans at first inspection. We may not be able to sort out CN352 as it is out of area and may have to assume the Motherwell box is setting up the crossing. I don't think it is relevant to your specific comments, but do note that the sim is 'set' for 2006 and some alterations were going on around Larbert at the time. Bill Log in to reply |
| Wrong signal aspects in the carmuirs area 04/04/2010 at 20:28 #8182 | |
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sparplu
18 posts |
CW 13 is indeed a double yellow when the route is set up for CEJ3 showing a proceed aspect. This situation has been like this since i started driving the route from 2004 as these routes had no apparent influence on the Larbert resignalling work so the 2006 time line should still be current. Log in to reply |
| Wrong signal aspects in the carmuirs area 08/04/2010 at 22:29 #8295 | |
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Firefly
521 posts |
Sparplu This is interesting information. You're observations are at odds with the aspect sequence charts that we have for the area. CSCOT is attempting to simulate the area as it was in 2004 and the aspect sequence is correct for that time. I'm guessing that the reason that CEJ3 WAS approach controlled Y to G is because you are transitioning from 4 aspect CW13 to 3 aspect CEJ3 and signals to Grangemouth? That said it's not entirely necessary to worry about the transition as it's the diverging route. Perhaps the 3 aspect signals have been replace by 4 aspects since 2004? Perhaps the signalling sighting committee saw a risk that was reduced by making CEJ3 approach controlled from yellow and this was subsequently re-visited and changed? I'll keep looking at it to see if I can figure out what the designer was trying to achieve. All I can say is CEJ3 works exactly as the 2004 signalling design shows. FF Log in to reply |
| Wrong signal aspects in the carmuirs area 08/04/2010 at 22:40 #8296 | |
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bill_gensheet
1318 posts |
I must be missing something in what you are saying here, so forgive the step by step.. How soon can you see CW13/24 as YY after you pass CW12 at FY ? Do you see it change up ? Where in this sequence can you say the sim go wrong ? With a route set through Carmuirs East, the sim initially has CW13/24 at Y With track circuit 385 occupied CW13/24 remains at Y, this is a long TC of 945m and includes the 60mph speed limit change. As soon as track circuit 386 becomes occupied, then CW13/24 goes to YY. This TC is only 170m long, so that is going to be around 140m from the signal as some of the TC is past the signal. Image of TC385 & 386 at the instant of TC386 going occupied, train still 140m back from signal.  regards Bill Log in to reply |
| Wrong signal aspects in the carmuirs area 09/04/2010 at 12:47 #8309 | |
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clive
2738 posts |
Log in to reply |
| Wrong signal aspects in the carmuirs area 09/04/2010 at 12:54 #8311 | |
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Firefly
521 posts |
ok I've thought about this a little more. I'm no longer thinking that they've done it because of the 4 to 3 transition because as I said previously it doesn't matter at a junction signal. The standard states:- "Where the transition occurs at a 4-aspect junction signal and only the diverging route(s) incorporate the 4-aspect to 3-aspect transition, the junction signal shall display a green aspect when the next signal on the diverging route(s) is displaying a single yellow aspect as part of a 3-aspect sequence." But this is not the case at Carmuirs West because we know and Sparplu has confirmed that CW13 shows maximum YY when the route is set towards CEJ12. So they've done something bespoke for some reason or other. Having looked at Google Earth I can see that CEJ3 is in direct line of sight of CW12 and only 2000m away (as the crow flies). Given that CEJ3 is a Dorman LED head you could argue that there is a significant read-through risk because a driver could see CEJ3 at green. That would make sense, and would be an explanation as to why our plans show CEJ3 released from Yellow, however it doesn't explain why Sparplu can see it at Green from CW12. Sparplu, are you 100% sure that you see CEJ3 at Green and not Yellow? Still digging Log in to reply |
| Wrong signal aspects in the carmuirs area 09/04/2010 at 15:36 #8317 | |
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sparplu
18 posts |
Firefly said:You can definitley see CEJ3 as a Green as you can look across (from CW12 when you have the flashing yellows to give you an idea if your going to be stopped or not) if you are being stopped at CEJ3 you can see the red as clearly as youcan the green signal. The only time you encouter the single yellow signal is CEJ10 is showing a red aspect. CW13 signal i don't know when it comes off as double yellow due to the curvature of the track as you don't see this signal until you are near or at the AWS magnet. Log in to reply |
| Wrong signal aspects in the carmuirs area 09/04/2010 at 15:53 #8319 | |
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Firefly
521 posts |
thanks for the info sparplu I'm still struggling to work out why CW13 is held to a double yellow especially if CEJ3 is showing a Green. If I understand what you are saying correctly you could have greens all the way to Falkirk and still you'll get a double yellow on CW13? The YY on CW13 would be sensible if CEJ3 was held at Y to prevent the risk of read through from CW12. However since CEJ3 is free to clear whenever it likes holding CW13 at YY serves no purpose. Log in to reply |
| Wrong signal aspects in the carmuirs area 09/04/2010 at 18:55 #8326 | |
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sparplu
18 posts |
Firefly said:The signalling sequence if the road is set all the way to Falkirk from Greenhill lower is as follows GJ433 double yellow flashing, CW12 single yellow flashing, CW13 Double yellow, CEJ3 Green, CEJ 10 Green, GH6 Single Yellow, GH4 Red. The double yellow at CW13 may be like the signal at Law Jct where the driver gets a feather and double yellow for going to Wishaw but if you are sat in the loop you actually observe the signal going to green once the loco or first coach of unit has actually passed the signal so the driver never actually see the signal change to green even though the next signal is showing a green signal. It may have something to do with the diverging junctions rather than anything else. Log in to reply |
| Wrong signal aspects in the carmuirs area 10/04/2010 at 06:20 #8340 | |
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Firefly
521 posts |
sparplu said:The double yellow at CW13 may be like the signal at Law Jct where the driver gets a feather and double yellow for going to Wishaw but if you are sat in the loop you actually observe the signal going to green once the loco or first coach of unit has actually passed the signal so the driver never actually see the signal change to green even though the next signal is showing a green signal. It may have something to do with the diverging junctions rather than anything else.There's no signalling principles in existence that explain why CW13 should be held at YY when all signals in advance are at green. We never release aspects after a train has passed a signal as that would serve no purpose. I'm quite certain that in the case you describe above the signal at Law Jnc will be stepping up to green after the loco has passed because a signal in advance has stepped up an aspect. (This could either be because of approach control, a set of barriers ahead or if it's between 2 boxes because the next signalman doesn't pull off until the train has passed the Law Jnc signal. There's only a couple of explanations for CW13 being restricted to a YY. 1) They don't want you receiving an AWS bell. 2) The original design required CEJ3 App Controlled from Yellow so there was no need to allow the circuitry in CW13's location to be able to show a Green with Feather. It was therefore not wired. At some point along the way they decided the approach control on CEJ3 was no longer required and either forgot or more likely decided there was little point in re-wiring CW13's circuitry. 3) There is a fault and CW13 should be showing a Green (right side failure) 4) There is a fault and CEJ3 should still be approach released from Yellow as per our design.(wrong side failure) I think number 2 is the most likely scenario although 1 could have some merit. I have enough faith in my colleagues to be able to say that scenario 4 is very unlikely. FF I'm in no doubt that CEJ3 was held at yellow until the train was the berth track is the read-through risk. Log in to reply |
| Wrong signal aspects in the carmuirs area 10/04/2010 at 16:49 #8358 | |
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sparplu
18 posts |
There is no read thru risk associted with the signal due to the curvature of the line and not being able to see the signal until you hit the AWS magnet (roughly 200m). With regard to Law Jct this area is completely controlled by Motherwell box and there is no crossings involved this may however be the case of going from 4 aspect to 3 aspect signalling which causes the signal to be held at the double yellow even though the next signal is showing green. Log in to reply |
| Wrong signal aspects in the carmuirs area 10/04/2010 at 20:21 #8362 | |
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Firefly
521 posts |
I'm guessing that only people involved in these schemes will know the true answers. All I can say is both scenarios are non-standard. FF Log in to reply |
| Wrong signal aspects in the carmuirs area 25/02/2011 at 10:57 #13782 | |
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fruitnnut
5 posts |
HI There, Just to clarify the aspects at Garnqueen Jn. As I work in Motherwell SC, I can confirm that when the route is set towards Motherwell and MG906 which protects Heatherbell LC, is at Red, the next signal in rear which is MG908, a 3 aspect colour light distant would be single yellow, therefore CN352 would show a double yellow. In the sim CN352 shows a green which would only happen if Heatherbell LC was lowered an dcrossing clear. Hope this clears this up. Henry (fruitnnut) Log in to reply |
| Wrong signal aspects in the carmuirs area 25/02/2011 at 20:13 #13791 | |
Peter Bennet
5362 posts |
Thanks for that Heatherbell is not simulated within CSCOT so it's always assumed down and clear when a train is routed from CN352. I could perhaps fiddle around with a random timer or something. Peter I identify as half man half biscuit - crumbs! Log in to reply |
| Wrong signal aspects in the carmuirs area 26/02/2011 at 16:53 #13794 | |
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Peter Bennet
5362 posts |
Peter Bennet said:Thanks for that Heatherbell is not simulated within CSCOT so it's always assumed down and clear when a train is routed from CN352. I could perhaps fiddle around with a random timer or something.Have inserted a 60-90 second delay in MG906 clearing, triggered by setting the "A" route from CN352, so you get a YY for a short period of time. Still not strictly correct as it could be that the crossing is down for a Down train already but short of simulating the whole crossing ( which imports some difficulties of its own) that's probably the best compromise. Peter I identify as half man half biscuit - crumbs! Log in to reply |