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| Absolute block signal lamp out bug 27/04/2023 at 11:52 #151526 | |
Robyn
74 posts |
I've just had a lamp out on Helsbys UP distant signal and that for.. 'reasons'.. has caused Frodsham to throw his UP section signal back w/out input from myself. That ain't how distant signals work chief. I'm running the user-made 1977 timetable in the 2018 era. Screenshot attached Could this be looked into, ta'  Post has attachments. Log in to view them. 7-5-5, closing of comment Log in to reply |
| Absolute block signal lamp out bug 27/04/2023 at 13:30 #151530 | |
flabberdacks
636 posts 
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The route is still set, so I'm not sure the bobby has 'thrown back' per se. There may be a lamp proving requirement at play - can't get a proceed aspect if the next distant isn't lit. I can see the risk they're trying to protect, if it's true. Log in to reply |
| Absolute block signal lamp out bug 27/04/2023 at 13:30 #151531 | |
TUT
532 posts |
RobJ in post 151526 said:That ain't how distant signals work chief.Well I mean it is insofar as: Quote: A train may approach a defective distant signal if it has been placed to, and kept at, caution and you are sure the correct aspect or indication is showing.Not the case Quote: You may also allow a train to approach a defective signal if you have made sure the correct proceed aspect or indication is being shown, it will not cause the driver to see an incorrect sequence and one of the following applies.Note the case "If none of the above apply" (they don't) "you must not allow a train to approach a defective signal until the driver has been told about the defect" (they haven't been told) and one of the following applies: "the train has been accepted by the next signal box" (it has). Now if I were to lose the lamp in a distant with a train accepted and the distant off what I would do is immediately replace it to on and see if I could get it to show caution. If it could not show any aspect whether it's worth contacting the box in rear and getting them to slam signals back is I suppose debatable but in this case it seems unnecessary. An urgent call to the driver on the GSM-R radio or getting signals put back might be warranted if the train was turning out at the junction or you risk the driver hitting the points too fast as they had no cautionary aspect. But in your case probably not necessary and you're right the lamp failure won't throw back a signal that's been pulled off automatically. However the DNC controls should prevent you from giving a line clear which will hold the section signal at danger for all subsequent trains, so it's a pretty reasonable compromise imho. Log in to reply |
| Absolute block signal lamp out question 27/04/2023 at 14:29 #151533 | |
headshot119
4869 posts |
You need to remember that SimSig was born primarily as an IECC simulator, we've stretched the specifications over the years to simulate mechanical signalling, absolute block, electric token block, NSTR, and various other things, we even stretched things to simulate signalling in an entirely different continent. For a bit more of an explanation of why this happens. In the data we're looking at a controlled signal, in this case FJ4, we setup the route between there and HY2, we need to add HY1 in for aspect sequencing purposes as it lies between FJ4 and HY2; this doesn't matter so much in this case as FJ4 is a two aspect signal and will always go to green and doesn't really care if HY1 is at yellow or green however next door at Norton the section signal NN3 is a four aspect so needs to know about Frodshams distant (In the older era). SimSigs core behaviour is if the exit signal at the end of the route, or any signal adding for aspect sequencing loses lamp proving, the entry signal in the route will revert. As TUT has touched on, in terms of absolute block, this gives a nice compromise to simulate the HN/DN controls, as it'll prevent you clearing the section signal. On an aside though, I know at least one box where the distant going dark next door reverts a signal, then again there's various other quirks that go on with it, so I won't say with conviction that was the original intention. "Passengers for New Lane, should be seated in the rear coach of the train " - Opinions are my own and not those of my employer Log in to reply |
| Absolute block signal lamp out question 27/04/2023 at 14:29 #151534 | |
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Robyn
74 posts |
flabberdacks in post 151530 said:The route is still set, so I'm not sure the bobby has 'thrown back' per se.He has thrown back, there were greens all the way to Mickle Trafford, Helsby went to pull off his distant to find it not proving OFF, yet that has somehow caused Frodsham to throw back his section signal to ON. (The route being 'set' is irrelevant because it was never cancelled by the player therefore it would still be 'set' ) In normal colour light TCB signalling an unlit aspect will always show red the block before, which is what it looks like has happened here. But because this is AB signalling that shouldn't happen. The distant being off has no baring whatsoever on what the box in rear does with his section signal. Frodsham got his LNC release, and pulled off. 7-5-5, closing of comment Last edited: 27/04/2023 at 14:31 by Robyn Reason: None given Log in to reply |
| Absolute block signal lamp out question 27/04/2023 at 14:40 #151535 | |
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flabberdacks
636 posts
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My interpretation of 'throwing back' is a route cancel, just so we're on the same page. A deliberate act by the signaller to return a signal to danger. As the signal stem is still white, the route isn't cancelled, the levers are all still pulled, but the stick won't come off because of (what looks to be) a lamp proving requirement. That's all. Log in to reply |
| Absolute block signal lamp out question 27/04/2023 at 15:07 #151537 | |
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TUT
532 posts |
flabberdacks in post 151535 said:My interpretation of 'throwing back' is a route cancel, just so we're on the same page. A deliberate act by the signaller to return a signal to danger.What RobJ is saying is that FJ4 was pulled, the signal did come off, but then when the distant at Helsby failed it returned to danger. This, he's right, isn't going to happen with a semaphore (which FJ4 was) and I don't think would generally happen with a colour light (which FJ4 is now) but I suppose it could be made to and headshot mentions a place where that does happen. But it would be unusual for FJ4 to be reverted in that way automatically, it would have to be replaced by the signaller, which is what SimSig has done, which arguably it shouldn't have. But as I say I think it's okay honestly, you shouldn't be able to give a line clear in that situation and the situation might very well warrant telling the driver of an approaching train as I say. If, depending on the fault, the block controls allow a line clear to be given drivers are still gonna have to be stopped and told at the section signal. There used to be a bell code 8-2 for use where there were no comms between boxes, but sadly they took that off us a few years back, which is a shame. Log in to reply |
| Absolute block signal lamp out question 27/04/2023 at 15:43 #151540 | |
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flabberdacks
636 posts
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Ah, thanks for the clarification. I'm just looking at the screenshot and seeing a colour light signal, didn't know it was semaphore.
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| Absolute block signal lamp out question 28/04/2023 at 20:55 #151580 | |
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Robyn
74 posts |
flabberdacks in post 151540 said:Ah, thanks for the clarification. I'm just looking at the screenshot and seeing a colour light signal, didn't know it was semaphore. That happens quite a lot in sims, sems represented as CLs, Shrewsbury is another example. 7-5-5, closing of comment Log in to reply |