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| Carmuirs Triangle Bell Codes 03/08/2010 at 16:58 #10423 | |
Neil_Scott
4 posts |
From my understanding of the area the 'Train Approaching' bell code was never used, and I've never seen it used in any signalbox, apart from those that have level crossing boxes in the block section. The signalmen at Carmuirs East, Carmuirs West and Larbert North simply offered on the train when they were in a position to and sent TES as indicated in the rule book. I suspect, however, that Larbert Junction was able to offer on a train to the East/West before receiving TES from Larbert North and likewise from Larbert Junction to Larbert North due to the closeness of the boxes. Danny252 said: In last night's MP session, I started wondering about whether or not the boxes on and around the Carmuirs Triangle (assuming that's its name!) would use "Train Approaching" (1-2-1) bell codes, due to the fact that the boxes are very close to eachother. Whilst I've not found anything online, I've put together a spreadsheet of possible bell codes that, when used, would allow a train to pass through without being checked by either homes or distants, the obvious exceptions being junctions where signals have warner routes/holds. Hopefully this is relatively close to the real working, but without box instructions, I can't be sure! Also, the real working may well have checked trains, dependent on the line speeds. Log in to reply |
| Carmuirs Triangle Bell Codes 03/08/2010 at 17:07 #10425 | |
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Danny252
1461 posts |
Neil, Now that I have some more (practical!) signalling knowledge, I now appreciate that Train Approaching is indeed a fairly rare bell signal - the only use I've seen for it is as a warning that a non-stop express is approaching, at a set of signalboxes where it would be impossible to stop said non-stop due to the lack of braking distance. I've also come to the opinion that SimSig bell signals end up being slower and more delayed compared to the real thing - I guess it's in part due the lack of seeing trains go by, and TCs being a bit harder to judge Danny Log in to reply |
| Carmuirs Triangle Bell Codes 03/08/2010 at 18:10 #10430 | |
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Late Turn
699 posts |
'Train Approaching' was, from my observations, used regularly at Lincoln pre-resignalling; in that case, it presumably gave guidance to the Signalmen to avoid delaying road traffic on the busy crossings, as well as helping regulation at West Holmes. 'Train Approaching' would never, ever, be used to ensure that signals were cleared because of insufficient braking distance (after all, the chap receiving Train Approaching won't necessarily be in a position to immediately offer the train forward); either a slot on the distant at the box in rear (so both boxes need to pull off through before the rear distant will come off), or some form of special working that requires C to accept the train from B before the latter can accept it from A (the Western did that heavily - can't remember the bell signal though)
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| Carmuirs Triangle Bell Codes 03/08/2010 at 18:43 #10433 | |
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Danny252
1461 posts |
Sorry, I wasn't clear there. In my example, A receives (and accepts) an ILC for an Express Passenger Train not stopping at Station Z (controlled by Boxes B, C and D). B, C and D do not have distants far enough out (D's outermost distant is 560 yards from the Homes) for this Non-Stop train, and hence cannot accept it until the line is clear all the way to E. Train Approaching is sent from A and passed down to D, so that B-D can clear the route in preparation to accept the non-stop (bell code 3-3-3), and then when A sends the ILC to B, it must be accepted all the way to E before being let through. In the opposite direction, the same is true from D, where C, B and (I think) A must all accept. (If you're desperate, the boxes are Cowley Bridge Jn, Exeter East, Exeter Middle, Exeter West and City Basin Jn in order) Log in to reply |
| Carmuirs Triangle Bell Codes 03/08/2010 at 19:06 #10435 | |
DriverCurran
688 posts |
Late turn, Although not a GW man I do recall reading about the use of 2-2-2 and 2-2-2-2 (or something very similiar) this was used when boxes were very close together, however the exact methord of working I am not fully familiar with, but it was I understand to have something to do with Box A maintaining his distant at caution until all boxes in the group could accept the train. Paul You have to get a red before you can get any other colour Log in to reply |
| Carmuirs Triangle Bell Codes 03/08/2010 at 19:29 #10437 | |
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Neil_Scott
4 posts |
DriverCurran said:Late turn, Although not a GW man I do recall reading about the use of 2-2-2 and 2-2-2-2 (or something very similiar) this was used when boxes were very close together, however the exact methord of working I am not fully familiar with, but it was I understand to have something to do with Box A maintaining his distant at caution until all boxes in the group could accept the train.We use 2-2-2 at WTJ and WSH for permissive working and from Henwick to WSH as well. Log in to reply |
| Carmuirs Triangle Bell Codes 03/08/2010 at 20:40 #10443 | |
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Late Turn
699 posts |
Ever useful, the previous use of 2-2-2 is explained here (the current use at Worcester doesn't sound like it performs the same purpose at the old Western reg 4A described in that link). In summary, A must not clear his distant until the train (regardless of type, presumably) has been accepted normally by B; in turn, B must offer the train to C (and have it accepted) before he can accept it from A. If B isn't in a position to offer it forward immediately, he accepts it with 2-2-2 instead; A then maintains his distant signal at Caution. Danny, there's no provision in the current regs (ok, I have checked, and of course it's been removed from the Rule Book altogether now!) to send 1-2-1 before a train has been accepted; its intended use is exactly as described earlier, and it'll almost certainly be used for that purpose in at least one direction when Swithland Sidings box is commissioned on the GCR. I'm not doubting that it was used at Exeter, but what was the point? Surely if you're going to 'clear the way' for the express, you might as well just offer it forward and be done with it? Tom Log in to reply |
| Carmuirs Triangle Bell Codes 03/08/2010 at 20:53 #10444 | |
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Danny252
1461 posts |
Tom, It is/was (depends how you view the box simulations at Crewe!) fairly possible to have some fairly long shunts going on at Exeter, which block the clearing point for the Down Main. In addition, accepting a train from Exeter Central (Southern) would foul this. For example, a shunt may move ECS from the Goods Yard into Platform one, blocking the main. The pilot will then come off and wait on the main whilst the train engine moves across the whole junction as well. If the 3-3-3 came through and you were halfway through a shunt, it's possible you couldn't clear a route before the non-stop train was brought to a (possibly somewhat grinding) halt all the way back at Cowley Bridge - causing irate footplate crews, passengers and inspectors! However, by getting the 1-2-1, you know to clear the route before the 3-3-3 arrives, and have an idea of how long you have to do so. You also save actually blocking the main for too long a time - it might be possible to get a set of banking engines back down from Exeter Central before the 3-3-3, for example. Danny Log in to reply |
| Carmuirs Triangle Bell Codes 03/08/2010 at 20:58 #10445 | |
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Late Turn
699 posts |
Fair enough, I can see how it might be useful in that case, but I'm sure that's a very specific, and quite extensive, amendment (unique?) to the general principle of 1-2-1. Thanks for taking the time to explain though!
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| Carmuirs Triangle Bell Codes 03/08/2010 at 21:08 #10446 | |
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Danny252
1461 posts |
I'm starting to think 1-2-1 was a code put in almost solely for use in specific cases - I've yet to find any rule and regulation covering a generic use.
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| Carmuirs Triangle Bell Codes 03/08/2010 at 21:14 #10447 | |
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Adrian the Rock
111 posts |
Neil_Scott said:We use 2-2-2 at WTJ and WSH for permissive working and from Henwick to WSH as well. " said: Ever useful, the previous use of 2-2-2 is explained here (the current use at Worcester doesn't sound like it performs the same purpose at the old Western reg 4A described in that link). In summary, A must not clear his distant until the train (regardless of type, presumably) has been accepted normally by B; in turn, B must offer the train to C (and have it accepted) before he can accept it from A. If B isn't in a position to offer it forward immediately, he accepts it with 2-2-2 instead; A then maintains his distant signal at Caution. The original 2-2-2 - the famous "line clear to clearing point only" - is as described by Late Turn above. The current use of the same code at Worcester is indeed a recently introduced special bell signal to replace the old 3-5-5, which was no longer allowed in the updated December 2007 rulebook except in cases of SLW or T3 posessions. So the Worcester 2-2-2 could loosely be described as "line clear to clearing point - NOT"! BTW I didn't know this was also used between Henwick and WSH (as well as WTJ-WSH). One thing I am curious to know: how is Henwick required to signal a train accepted with 2-2-2 in this latest version of the rules/special box instructions? Log in to reply |
| Carmuirs Triangle Bell Codes 03/08/2010 at 21:25 #10448 | |
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Late Turn
699 posts |
The generic use of 1-2-1 is exactly as described in the Rule Book (until it was removed at least!) - generally sent upon receipt of TES from box in rear, unless SBSIs state otherwise. On the GCR for example, I'd envisage it being sent from Rothley to Swithland at some defined time - if the latter offers forward upon receipt of ILC, Quorn's clearing point will be tied up unnecessarily (especially as it's not easy for Rothley to judge when to offer the train to Swithland - there's no guaranteed means of receiving information of departures from Leicester, on the single line) ; if Swithland waits for TES from Rothley, the train will already be passing the distant.
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| Carmuirs Triangle Bell Codes 03/08/2010 at 21:29 #10449 | |
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Danny252
1461 posts |
But the rule doesn't actually state when it should be used - that's always noted in SBSIs, correct? Similar to Reg 5 Acceptances, which can only be used in normal situations when specially authorised, I guess.
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| Carmuirs Triangle Bell Codes 03/08/2010 at 21:36 #10450 | |
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Late Turn
699 posts |
Yes, quite right - it's my understanding that it was usually sent upon receipt of TES, though that didn't appear to be the case at Lincoln and I doubt it'll be the case on the GCR.
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