RMweb Premium NWJ Posted May 30, 2015 RMweb Premium Share Posted May 30, 2015 Hopefully somebody can help to resolve this problem. Those who follow the Layout Topics closely my know that I am working on Halberford which is very much based on Totnes, albeit a little compressed. Looking at the SB diagram and locking tables (attached), I have worked out most of the moves that can be made, but there are a couple of queries I have over the operation. with reference to the highlighted disc signal. The first one I think I have resolved, and that is linked to 44, 49 & 50. 44 is for the two goods shed roads. 49 is Down Platform to Down Main and 50 is Down Platform to Up Main. Looking at Totnes, the Down line would presumably be used for accessing the Quay branch, working wrong line to signal 88, or to the Down Goods Loop, but would it be likely to use 49 for a train leaving the Down Platform to access the Up Main via the crossover (57)? If this is the case, why is the move also duplicated using 50? My second query is regarding a similar duplication linked with 66, 69 & 67. 66 is Up Main to Up Platform, 67 is Up Main to Down Main and I believe 69 is Up Main to Down Platform, using the crossover (53). If this is so, why again is there the duplication and why would there not be any access to the Up Platform Loop? Many Thanks Neil Link to post Share on other sites More sharing options...
RMweb Premium Grovenor Posted May 31, 2015 RMweb Premium Share Posted May 31, 2015 My second query is regarding a similar duplication linked with 66, 69 & 67. 66 is Up Main to Up Platform, 67 is Up Main to Down Main and I believe 69 is Up Main to Down Platform, using the crossover (53). If this is so, why again is there the duplication and why would there not be any access to the Up Platform Loop? Access to the Up platform is via signal 66. Stacked discs are arranged that the top disc reads to the leftmost route, and so on until the bottom disc leads to the rightmost route. Alternative routes are provided to give some flexibility, eg when using 67 you may have a train standing at 105 and thus need to use 69 instead, or a train standing at 4 when you would have to use 67. Regards Keith Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted May 31, 2015 RMweb Gold Share Posted May 31, 2015 All very simple really but it has to be studied in the context of the history of the place. If you look carefully at the part of the diagram you have show you will see there is a Facing Point Lock (FPL) on the B (Up Main) end of 56 crossover - so obviously it was there to allow a passenger train to run from the UP Main, in the wrong direction, towards the Down side; this crossover was no doubt provided to allow running movements from the Up Main to the Downside when Ashburton Jcn signalbox was closed. Plus it also created a mainlines trailing crossover at the east end which had not existed previously - so actually there was no direct duplication of facilities but simply an additional route created between the Down Platform line and the Up Main. Meanwhile the provision of disc 66 provided a signalled route at the east end to cross the stock of an arriving Ashburton branch train to access the Up platform - probably putting right what had previously been an unsignalled move. As Grovenor has already point out dis 66 read to the Up platform - fully confirmed by the locking chart which shows it led by 55. Link to post Share on other sites More sharing options...
RMweb Premium Grovenor Posted May 31, 2015 RMweb Premium Share Posted May 31, 2015 f you look carefully at the part of the diagram you have show you will see there is a Facing Point Lock (FPL) on the B (Up Main) end of 56 crossover - Pity the diagram is incomplete and does not show signals 106 and 107 that are released by that fpl. Keith Link to post Share on other sites More sharing options...
RMweb Premium NWJ Posted May 31, 2015 Author RMweb Premium Share Posted May 31, 2015 Many thanks to you both, Keith and Mike, for resolving this for me. Link to post Share on other sites More sharing options...
RMweb Premium NWJ Posted June 1, 2015 Author RMweb Premium Share Posted June 1, 2015 Further to your comments, Mike and Keith, I have attached the missing part of the diagram which includes 106 and 107, the home signals on the Ashburton Branch, so as you implied, Mike, this crossover was for access to the Down Line, replacing the original Ashburton Junction. According to the locking table, 106 is released by 58, 63 and 67 and 107 by 58 and 63. I presume that it is possible, looking at the table, to cross over to the down line from the up main or up loop from discs 70 or 71 using either crossover at 53 or 57? Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted June 1, 2015 RMweb Gold Share Posted June 1, 2015 Simple answer to the simple final question is 'yes' - if you look at the locking chart you will see there is a conditional (in brackets) release for 69 which allows that, there are also conditional releases on both 70 and 71, and some conditional locks. The locking on 107 is standard Reading locking which one of our Chief Dis always used to express as 'the Western locked two back' - meaning that two stop signals in rear of any points were locked (or in this case released) by them. In reality all this does as far as train arriving on the branch is concerned is to additionally enforce the Block Regulations by means of the interlocking as it makes t impossible for a train to approach signal 106 unless the road is set in advance of it. Link to post Share on other sites More sharing options...
RMweb Premium NWJ Posted June 1, 2015 Author RMweb Premium Share Posted June 1, 2015 Simple answer to the simple final question is 'yes' - if you look at the locking chart you will see there is a conditional (in brackets) release for 69 which allows that, there are also conditional releases on both 70 and 71, and some conditional locks. The locking on 107 is standard Reading locking which one of our Chief Dis always used to express as 'the Western locked two back' - meaning that two stop signals in rear of any points were locked (or in this case released) by them. In reality all this does as far as train arriving on the branch is concerned is to additionally enforce the Block Regulations by means of the interlocking as it makes t impossible for a train to approach signal 106 unless the road is set in advance of it. Thanks for confirming my thoughts, Mike, and the useful explanation regarding the locking on 107. Now the challenge is to get this all in place on Halberford... Link to post Share on other sites More sharing options...
brianusa Posted June 1, 2015 Share Posted June 1, 2015 Thanks for all this info; I'm always interested in signalling but sadly don't know much about it. Also I was never quite sure where the Quay branch left the main until recently so I appreciate this topic. Being of a certain age, I can remember the crossing in use on the main road! Brian. Link to post Share on other sites More sharing options...
RMweb Premium NWJ Posted July 20, 2015 Author RMweb Premium Share Posted July 20, 2015 Another query regarding Totnes with reference to the diagram provided by the Signalling Record Society of Totnes box in 1958 I am wondering about the B which is marked on signal 100, the Down Advanced Starter. A photo I have seen in one of my collection of books shows a freight waiting for a banking engine on the Down line approaching this signal, so would this be the stopping point for any train requiring banking up the banks towards Tigley and Rattery? This would then also explain the Calling On signals at 97 and 96, allowing the Banker forwards into this occupied section. Does anybody know whether Banking engines would have been attached in Totnes station? Thanks for the help, Neil Link to post Share on other sites More sharing options...
RailWest Posted July 20, 2015 Share Posted July 20, 2015 The 'B' on a signal post is simply the WR convention for marking the fact that the signal is electrically locked and 'release by the Block' - ie released by 'Line Clear' pegged up by the signalman at the far end of the block section. It is purely a marking on the signal-box diagram, not on the actual signal and nothing to do with bankers (engines or money-grabbers!). Link to post Share on other sites More sharing options...
RMweb Premium NWJ Posted July 20, 2015 Author RMweb Premium Share Posted July 20, 2015 Thank you, Chris. That's another puzzle resolved. Neil Link to post Share on other sites More sharing options...
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