North End
Beneath Newington Causeway
Posts: 1,769
|
Post by North End on Jul 6, 2018 19:31:41 GMT
Thanks for that, PicNT. It just shows how unreliable your (or rather my) memory can be. I had muddled up the trainee with the 2 yr driver. So all my comments about poor training letting a new driver think using anything other than a signal as a clear to start are null and void. I see what you mean about the unprofessional attitude, but I think that was almost certainly to do with being completely gutted about her error. It came across as if she didn't think it was too much of a problem, but, in reality, I suspect that was more her trying to convince herself that she wasn't as much of an idiot as she no doubt felt. I noted the supervisor saying that some drivers had seen that video 'half a dozen times'. I bet there isn’t a driver on the combine who hasn’t at some time gone to press the door buttons when they’ve heard the sound of points - indeed money has been spent silencing points at one or more locations so it’s clearly a risk taken seriously. No matter how hard one tries, sometimes one just naturally goes onto autopilot. This is where the value of routines comes in - if your autopilot routine means you check the signal again before moving off then it shouldn’t lead to a SPAD. Old-school drivers tend to find thisncomes more naturally - it’s said that when driving with a guard it was absolutely vital to re-check the starter before moving as it was not uncommon to get the bell on a red signal with certain guards!
|
|
rincew1nd
Administrator
Junior Under-wizzard of quiz
Posts: 10,235
|
Post by rincew1nd on Jul 6, 2018 20:16:00 GMT
On the mainline, the route indicator lights before the signal clears. I've always assumed this is deliberate, as if it happened the other way round a driver might respond to a clear signal apparently for the straight ahead route, only for the "feathers" to appear a moment later indicating you are routed over a diverging route - which may have a lower speed limit, or not be cleared for whatever it is you are driving, or simply not be where your passengers are expecting you to take them. The aspect won't change from stop to proceed until it is proved that the feathers are lit. This is to prevent the signal showing an incorrect indication. In a similar way on LU the green aspect will illuminate when the line is clear, then the trainstop will lower, then the red aspect will extinguish.
|
|
|
Post by superteacher on Jul 6, 2018 23:12:54 GMT
Anyway back on topic please. This thread is interesting but seems to be going in different directions. I may do a thread split tomorrow if I’m brave enough. But for now can we stick to doors and departure, thanks.
|
|
|
Post by banana99 on Jul 7, 2018 0:32:40 GMT
On the mainline, the route indicator lights before the signal clears. I've always assumed this is deliberate, as if it happened the other way round a driver might respond to a clear signal apparently for the straight ahead route, only for the "feathers" to appear a moment later indicating you are routed over a diverging route - which may have a lower speed limit, or not be cleared for whatever it is you are driving, or simply not be where your passengers are expecting you to take them. No. It's just a quirk of how the relays are wired.
|
|
|
Post by banana99 on Jul 7, 2018 0:33:49 GMT
I've always assumed this is deliberate, as if it happened the other way round a driver might respond to a clear signal apparently for the straight ahead route, only for the "feathers" to appear a moment later indicating you are routed over a diverging route - which may have a lower speed limit, or not be cleared for whatever it is you are driving, or simply not be where your passengers are expecting you to take them. The aspect won't change from stop to proceed until it is proved that the feathers are lit. This is to prevent the signal showing an incorrect indication. In a similar way on LU the green aspect will illuminate when the line is clear, then the trainstop will lower, then the red aspect will extinguish. Ummmm, not sure this is entirely correct, or if it is, not sure if it is entirely deliberate
|
|
rincew1nd
Administrator
Junior Under-wizzard of quiz
Posts: 10,235
|
Post by rincew1nd on Jul 7, 2018 7:11:01 GMT
The aspect won't change from stop to proceed until it is proved that the feathers are lit. This is to prevent the signal showing an incorrect indication. In a similar way on LU the green aspect will illuminate when the line is clear, then the trainstop will lower, then the red aspect will extinguish. Ummmm, not sure this is entirely correct, or if it is, not sure if it is entirely deliberate Which bit do you believe to be incorrect?
|
|
|
Post by 100andthirty on Jul 7, 2018 7:41:21 GMT
Ummmm, not sure this is entirely correct, or if it is, not sure if it is entirely deliberate Which bit do you believe to be incorrect? what banana99 said is deliberate. It was a straightforward way to indicate a train stop lowering fault, otherwise there would have been no need to interlock the red aspect with the train stop.
|
|
|
Post by banana99 on Jul 8, 2018 1:20:26 GMT
Ummmm, not sure this is entirely correct, or if it is, not sure if it is entirely deliberate Which bit do you believe to be incorrect? That on the mainline (BR/NR) that the junction indicator lights appear materially (i.e. perceptible to a human) before the proceed aspect is displayed.
|
|
rincew1nd
Administrator
Junior Under-wizzard of quiz
Posts: 10,235
|
Post by rincew1nd on Jul 8, 2018 1:32:57 GMT
It is less noticeable now that LED feathers are being fitted, but if you find a signal head that still has incandescent lamps, it's really obvious that the feathers light first.
|
|
Chris M
Global Moderator
Forum Quizmaster
Always happy to receive quiz ideas and pictures by email or PM
Posts: 19,412
|
Post by Chris M on Jul 8, 2018 1:36:21 GMT
In my (limited) experience of watching mainline signals change to display junction indicator lights, there is not normally a perceptible delay between the indicator lights and the proceed signal, but there was definitely a gap of multiple seconds on the occasion I reference above. I believe we have at least a couple of mainline drivers on this forum who will have seen far more signals change than I have.
Edit: I can't remember exactly when the incident I reference happened, but it was certainly in the era of incandescent signals - I'd hazard a guess of circa 2004.
|
|
|
Post by goldenarrow on Nov 11, 2018 16:26:10 GMT
I'd meant to plug this a while back but never got round to it, I have seen on a few occasions if trains are being regulated at South Harrow during the winter months either due to gaps or timetabled dwells, certain drivers will use selective door close until their allotted departure time. Until then I hadn't realised that feature was still used. The video has captured this in action at Acton Town.
|
|
|
Post by superteacher on Nov 11, 2018 21:21:48 GMT
Haven’t seen that used in years!
|
|
|
Post by PiccNT on Nov 12, 2018 1:54:35 GMT
I used that last winter when really cold. We are instructed to fully open the doors before closing them if we use the selective function.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 12, 2018 19:10:31 GMT
In my (limited) experience of watching mainline signals change to display junction indicator lights, there is not normally a perceptible delay between the indicator lights and the proceed signal, but there was definitely a gap of multiple seconds on the occasion I reference above. I believe we have at least a couple of mainline drivers on this forum who will have seen far more signals change than I have. Edit: I can't remember exactly when the incident I reference happened, but it was certainly in the era of incandescent signals - I'd hazard a guess of circa 2004. There is a checking relay which needs to operate once the route lights light up as a certain number of filaments need to light before the signal shows a proceed aspect. A common failure mode is you have a stop aspect but the route lights lit this is where the checking relay fails due to not enough filaments / enough current draw
|
|
Tom
Administrator
Signalfel?
Posts: 4,100
|
Post by Tom on Nov 12, 2018 22:39:10 GMT
On the main line the delay can often be longer depending on the technology in use, Solid State Interlockings are generally slower to respond than relay-based ones.
|
|
Chris M
Global Moderator
Forum Quizmaster
Always happy to receive quiz ideas and pictures by email or PM
Posts: 19,412
|
Post by Chris M on Nov 12, 2018 23:06:27 GMT
I suspect that on this occasion the speed was a result of a human having to perform two (or more) consecutive actions in sequence.
|
|