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| Re: "Call-on set from signal in rear" message 29/11/2011 at 18:29 #24046 | |
jc92
3690 posts |
borough market junctions at york now isnt it? doesnt look that big so im suprised it was a two man job
"We don't stop camborne wednesdays" Log in to reply |
| Re: "Call-on set from signal in rear" message 29/11/2011 at 21:19 #24070 | |
mfcooper
707 posts |
" said:borough market junctions at york now isnt it? doesnt look that big so im suprised it was a two man job If you've ever been to London Bridge and seen the sheer number of trains over Borough Market Junction, then you might begin to understand why it was double manned! Regarding TORR in SimSig, there are many locations that SimSig simulates that do not have TORR. The option to have TOOR on should be included in a sim is up to the developer. There are arguments for true accuracy, and then there are arguments for "what would happen if the area were converted into an IECC?". And in real life there are many people covering an area like Bristol (which does not have TORR in the period simulated), but we may try and play the sim alone. This means an option for TORR allows for solo play, and whilst not being truly accurate is, I believe, an acceptable compromise. Log in to reply |
| Re: "Call-on set from signal in rear" message 29/11/2011 at 21:34 #24072 | |
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clive
2789 posts |
" said:I agree it would seem implausible for a signalling system to be able to tell whether joining is complete, indicating another compromise SimSig has to make with the real world.There is no compromise involved here. The signalling isn't looking at whether the trains are joining or even whether they are moving. All it does is looks at which track circuits are occupied and for how long. That's what happens in both real life and SimSig. Log in to reply |
| Re: "Call-on set from signal in rear" message 29/11/2011 at 21:43 #24074 | |
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clive
2789 posts |
" said:So you're saying there may be some sims lacking TORR? I haven't come across one yet, in fact, haven't even had to bother to look for it.Okay, here's the situation. Originally Geoff put TORR into the core code without the option of omitting it. At a later point he made it an option. In the real world, older panels didn't have TORR. The signallers had to cancel each route behind each train. BR were very nervous about a train being able to cancel a route, because they were concerned that track circuit faults could simulate a train and cause the route to be cancelled right in front of a train (or, even worse, as the train passed the signal so the driver didn't see it). Eventually a workable solution was found and was installed in some new panels (I think London Bridge was the first to get it). Because of the concern about wrong-side failures, there was always a disable switch in the signal box that meant TORR could be turned off if something went wrong. SSIs can make more checks, and so TORR is standard with them. I don't know if the SSI code has a disable feature. Older sims had TORR whether or not the real box had it. Cambridge and Peterborough are examples. The authors of newer sims have decided what to do. For example, Euston didn't have TORR, but I felt that it made the game more playable for a single user who wasn't an expert, so it's an option when you start the simuation. Log in to reply |
| Re: "Call-on set from signal in rear" message 29/11/2011 at 22:02 #24079 | |
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maxand
1637 posts |
Thanks Firefly for your reply and the great panel pics. I see what you mean about the set routes standing out. Also interesting that the berths (have to) occupy fixed positions on these boards and can't jump ahead of the train, as they can on computer screens! Thanks too for the 1994 BRB document on the TORR standard. Under Special Operating Conditions it does mention turning TORR off, for example when a train overshoots or breaks down just after passing a signal, stopping with its rear behind the signal, then has to set back (reverse). Under those conditions one wouldn't want TORR to operate until the train has moved forwards again and cleared the block entirely. But surely this is a case of switching TORR off locally rather than for the whole panel. In 6.6 it also states: Quote: TORR must be inhibited if a signal is set to work automatically. If automatic operation is cancelled and the route remains set, TORR shall operate for the next train movement. But this doesn't require switching TORR off manually. Khalid, if I appear to be contradicting myself it may be because veterans such as you have indeed accumulated so much experience that you find no difficulty with situations that leave me floundering. To paraphrase an old joke, there seems to be a right way, a wrong way and a railways way of doing things. The logic behind the last one may not be immediately apparent, but it's there all right and has a long history (thanks again Keith Barber). That's why I appreciate all you guys going out of your way to give me (and any other newbie who bothers to read through the forums) the benefit of your years of training. (Added) Clive, I see you posted while I was writing this. Agree that needing to switch off TORR manually in real life seems like the man with the red flag walking ahead of an early locomotive. I appreciate the brief history of TORR as used in SimSig. It all makes sense now. Last edited: 29/11/2011 at 22:13 by maxand Reason: corrected "overshooting a red signal" Log in to reply |
| Re: "Call-on set from signal in rear" message 29/11/2011 at 22:30 #24082 | |
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Firefly
521 posts |
Quote:Under Special Operating Conditions it does mention turning TORR off, for example when a train overshoots or breaks down just after passing a signal, stopping with its rear behind the signal, then has to set back (reverse).The Special Operating Conditions is talking about the design requirements of the system. What it is saying is that the interlocking must not release the route if a train has not completely passed the signal. It's not an operating instruction, it's a design specification for certain operating conditions. Log in to reply |
| Re: "Call-on set from signal in rear" message 29/11/2011 at 22:39 #24083 | |
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Firefly
521 posts |
Quote:Also interesting that the berths (have to) occupy fixed positions on these boards and can't jump ahead of the train, as they can on computer screens!On most panels (not some of the older ones!) every signal has a TD berth. As soon as the train passes the signal and occupies the replacement track circuit the TD will step (jump) into the next berth. Simsig simulations only usually have berths where they actually exist on the real panels. So no difference! FF Log in to reply |
| Re: "Call-on set from signal in rear" message 29/11/2011 at 22:39 #24084 | |
Peter Bennet
5402 posts |
" said:Thanks Firefly for your reply and the great panel pics. I see what you mean about the set routes standing out. Also interesting that the berths (have to) occupy fixed positions on these boards and can't jump ahead of the train, as they can on computer screens! No it's exactly the same, just the Berths in SimSig are generally not shown when not occupied (though they could be). " said: If you set a controlled signal to Auto then the route is recalled automatically- whether that's because TORR is swiched off or because the logic pulls the route then resets I don't know. Peter I identify as half man half biscuit - crumbs! Log in to reply |
| Re: "Call-on set from signal in rear" message 29/11/2011 at 22:55 #24087 | |
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clive
2789 posts |
" said:Also interesting that the berths (have to) occupy fixed positions on these boards and can't jump ahead of the train, as they can on computer screens!However, they're in fixed places on the screens. It's just that when they're empty they're shown as a piece of track. Quote: Under those conditions one wouldn't want TORR to operate until the train has moved forwards again and cleared the block entirely. But surely this is a case of switching TORR off locally rather than for the whole panel.It will be switching it off for a section of the panel. There isn't one "disable TORR" switch per signal; rather there will be one per area or even one for the whole signal box. Quote: Quote:No, that's a circuit design requirement.TORR must be inhibited if a signal is set to work automatically. If automatic operation is cancelled and the route remains set, TORR shall operate for the next train movement. Log in to reply |
| Re: "Call-on set from signal in rear" message 29/11/2011 at 22:58 #24088 | |
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Firefly
521 posts |
Quote:If you set a controlled signal to Auto then the route is recalled automatically- whether that's because TORR is swiched off or because the logic pulls the route then resets I don't know.A logic requirement of TORR is that the signal must be "disengaged" and "free of approach locking" If a signal is selected to auto the system prevents it disengaging. Therefore, if it's not disengaged it can't TORR FF Log in to reply |