class411
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Post by class411 on May 31, 2018 16:18:42 GMT
I do know that they reverse escalator direction, frequently at weekends, in order to balance out wear, . It's not going to be very effective if you compare five heavily loaded days with two lightly loaded ones, but as Tesco tell us: Every little bit helps.
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class411
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Post by class411 on May 31, 2018 16:16:55 GMT
I wonder if escalators wear out quicker if they are predominantly fully loaded, half-loaded or unloaded? I've just spend a good half hour googling this question, and I've not found a definitive answer, but escalators that are built to carry more people and/or heavier loads are sturdier than those designed for lighter duties, and the trial to use cheaper, lighter escalators at Bank DLR was not a success (they had to be replaced after a significantly shorter service life than the Underground standard ones). Together these suggest that an fully loaded escalator would wear out quicker than an unloaded one. Where half-loading comes in to this I don't know. I found much uninformed speculation that escalators where people stand on one side only would wear out quicker (due to uneven wear) than ones where people stand on both, that people walking on escalators cause more wear than people standing on them, and that down escalators last longer than up escalators, but no confirmation of any of these f rom people who actually know what they are talking about. This is the thing. When I saw the question I speculated a lot but as I don't know for certain, and as some of these questions have counter-intuitive answers I refrained from posting. However, I think there are some things you can say that might help people form their own opinions: 1) Unless the mechanism is entirely frictionless (which it isn't), a more heavily loaded escalator will wear faster than a less heavily loaded one. So fully loaded will wear fastest, unloaded slowest, and half loaded somewhere in the middle. As far as I'm aware the relationship of force to wear by friction is linear, but I wouldn't bet money on it! 2) Unless the supporting mechanism involves a cantilever (which would be absurd unless you were going for some high art installation that would be wildly inappropriate in an underground station) the total wear will not be greater because of people standing (predominantly) on one side. However, the wear will be uneven, so the time between the whole thing having to be taken apart would be less, and as this is likely to be costlier than the worn parts, it should be a consideration, which makes reversing the escalator from time to time an attractive proposition if it is practical, taking into account other factors of passenger flow. 3) Up escalators will wear very slightly faster because they have to accelerate each person using them to the vertical speed of the unit. It's as if each person weighed a bit more for a second or two. However, the difference will be small compared to the overall wear. (Similarly, on a down escalator, each person will effectively weigh a little less as gravity will do the job of accelerating them to the downward speed of the unit. 4) People walking on the escalator is a very tricky one as their weight will momentarily increase each time the push down to step (obviously more so if they are going up), but they will be on the unit for a shorter period of time. As I said, these are just factors to consider - although I'm pretty confident that (1) is rock solid. For (2) to (4) all sorts of complexities could yield a counter intuitive result.
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class411
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Post by class411 on May 30, 2018 18:36:41 GMT
I can see problems here when they try and rosta White City drivers to do a shift on the Buenos Aires metro.
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Post by class411 on May 30, 2018 17:46:22 GMT
The new displays carry more information, but the display screens and consequently the font is too small and the locations of the signs are simply careless. It sometimes seems as if not one single iota of intelligence has been used in the placement of the describers. There are many stations where the describer is out of view for a lot of the length of the platform because they've plonked some other piece of platform ceiling furniture in the way, or placed the describer where it is blocked by some extant obstruction.
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Post by class411 on May 25, 2018 7:57:57 GMT
And two TD converter units TWO TD converter units, and they still couldn't get it right? I'm not even going to ask what a PIMS unit or TD converter are. Let's just say that for all the use they were, they might just as well have said the next train is arriving at Pims o'clock.
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Post by class411 on May 25, 2018 7:55:07 GMT
Couldn't have been thirty years - the station was only refurbished in the 1990s. From what I can remember (and DistrictSOM will no doubt correct me) the DMI at Hammersmith was driven off a PIMS unit which dated it to the mid-late 1990s? It may well have been updated, but they didn't actually make the data worse, it simply didn't improve. (I'm not even sure what, if anything, they had before the refurb.) I just know that since I started using the station in the late eighties there has always been a problem of a lack of useful information when there are delays on the district line - hence the problem is ~ 30 years old. It's particularly unfortunate at Hammersmith (and Baron's Court) as being aware that there is a long delay on the District can allow you to relatively easily use an alternative route and avoid missing connexions. And on a general point; why would a station refurbishment affect the accuracy of the train describers? Surely that is something that depends on the signalling, not the aesthetics of the environment.
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Post by class411 on May 21, 2018 18:50:52 GMT
You are not allowed to change the character of a listed building without appropriate consent. What constitutes a change in the character will depend on on the nature of the proposed works and the nature of the listing (what specifically is listed and why - for example the steps might be an integral part of the listing). Without knowing the details of either it is impossible to form an opinion about whether the ramp would be appropriate or not. Even they don't alter the character of the building, the council are correct to say that works cannot be done without prior approval - planning permission may also be needed. Disability discrimination requires that "reasonable" adjustments be made - adjustments that require changes to the character of a listed building are not normally going to be reasonable. I do actually know all this. I just find it rather sad that despite all the hyperbole about equal rights legislation and an inclusive society, the rights of the disabled take second place to aesthetic considerations regarding an area that is not even visible to the general public.
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Post by class411 on May 21, 2018 18:43:02 GMT
I arrived a Hammersmith District Line Eastbound, today, and discovered that the old single line train describer, that has been showing a vast quantity of spurious information for at least thirty years, has been replaced by a three line unit that actually seems to be providing accurate information. Admittedly a sample size of one is not much to go on, but it did say "Upminster 3 mins", which counted down until a train arrived in the specified time frame, a feat I have never seen before on that platform! I'm glad we can finally put that one to bed 411........ You're glad, I'm glad, and I'll bet a pound to a penny that the commuters who regularly use that platform are extremely glad - particularly if there are delays on the District, and they want to go further than Earl's Court.
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Post by class411 on May 21, 2018 17:28:11 GMT
I arrived a Hammersmith District Line Eastbound, today, and discovered that the old single line train describer, that has been showing a vast quantity of spurious information for at least thirty years, has been replaced by a three line unit that actually seems to be providing accurate information. Admittedly a sample size of one is not much to go on, but it did say "Upminster 3 mins", which counted down until a train arrived in the specified time frame, a feat I have never seen before on that platform!
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Post by class411 on May 21, 2018 17:22:21 GMT
Poe's law at work here. There are so many barmy things going on you never know. True story: One of my sister's hotels has a garden that is only accessible via a very steep set of steps. She decided to have a ramp put in so that less able guests could enjoy the garden. The ramp is installed and much appreciated. Then the local council steps in and tells her that as it's a Grade 1 listed building she can't add the ramp. Who knew that listed building legislation trumped disability discrimination legislation? I would have thought it was common knowledge that you can't make alternations to a Listed building without consent from the local council. Indeed it is, but in this case there was no change to the building; just the provision of a free standing facility to provide a means for disabled people to enjoy the same access as the able bodied.
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Post by class411 on Apr 26, 2018 16:30:23 GMT
Would there be an alternative power source in this eventuality? I’d be shocked if there wasn’t. Or not.
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Apr 26, 2018 16:28:16 GMT
Post by class411 on Apr 26, 2018 16:28:16 GMT
That's the difference between "new boys" and the old skool. We all know what notching up is. To open the deadman to first notch to jog the train then shut off immediately. This may be used by the motorman to either speed the guard up or to try to shift a sticky door. I doubt if the same could be done on modern stock, too many interlocks! I remember this quite vividly. As a kid coming back from my grans in Shephers Bush, when we changed at TCR for the Northern Line to Stockwell, the trains were heaving with soldiers and sailors. At Waterloo it took longer for them to all pile out and the motorman would 'notch up'The first time I witnessed it I thought the train was leaving with all the doors open! Often saw the guard use the 'speakerphone' to advise the motorman of the delay. I keep reading people talking about 'getting the pilot light' when the doors are closed, so how could the driver energise the motors when passenger doors were still open (to let the squaddies out)?
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Apr 26, 2018 16:26:50 GMT
Post by class411 on Apr 26, 2018 16:26:50 GMT
I've checked and 'notch-up' is not in the terminology list. Sounds intriguing, though. Assuming he's not going to actually move the train, the only think I can think of is momentarily applying power against the brakes, which seems hard to believe. Or is it a signalling term? That's the difference between "new boys" and the old skool. We all know what notching up is. To open the deadman to first notch to jog the train then shut off immediately. This may be used by the motorman to either speed the guard up or to try to shift a sticky door. I doubt if the same could be done on modern stock, too many interlocks! Well, in my case, it's noting to do with 'old school' because I'm not a train driver. Although when my love of the underground started I'm sure notching up was still a thing.
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Post by class411 on Apr 25, 2018 10:51:37 GMT
Is there a CrossRail / Elizabeth Line one yet? There's one kicking about taken on a works train showing a drivers eye view the tunnels from east of Woolwich through to west of Paddington. Lots of speeding up and editing and no proper soundtrack though. Nice clean tunnels, innit? On a serious note, are they going to keep that tunnel lighting on all the time during operating hours, or is it just for maintenance?
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Post by class411 on Apr 23, 2018 11:18:04 GMT
Interesting to note that people are wanting to board it at Earls Court. What was the purpose of the run? Trials for Dieselisation? We had that on Tyneside. Dieselisation of what? Has there ever been a case of an electrified line changing to diesel operation?
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Post by class411 on Apr 22, 2018 14:18:27 GMT
The management of the stations may have changed, but I understand the track and signalling is still NR's. There is precedent on the Wimbledon line, where the line itself is now owned by LUL, but still uses NR signalling. There was an oddity at East Putney whereby although the only trains that stopped there in passenger service were LU, it was an NR station, so you would see people smoking as underground trains pulled in which was odd. Presumably the same situation obtained at a few stations but was East Putney the only one where there was NO NR passenger activity?
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Post by class411 on Apr 21, 2018 9:57:00 GMT
This afternoon I caught an eastbound District line train from Kew Gardens. Shortly before it arrived the automated announcement was made, in the National Rail format, that "the next train is a London Underground service to Upminster, calling at Gunnersbury and Upminster". In reality it actually stopped at every station to at least Westminster (where I alighted). I presume the reason is that the National Rail database of stations doesn't know about all the intermediate LU-only stations (although it does seem to know about Turnham Green), but there really ought to be an alternative that doesn't involve misleading people about where a train will (not) call. Possibly teething problems? I've used Kew Gardens countless times, and I've never heard an announcement, so unless they are peak morning hours only, I'd guess this is a new system.
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Post by class411 on Apr 17, 2018 19:11:15 GMT
Women voting used to be sarcasm. I'm amazed that railway signalling has been allowed to fall so far behind in catering for this not-unusual disorder. No road traffic signal would ever be considered if it couldn't be understood clearly by a person with red/green deficiency. Let's face it; far stupider things have received the attention of the radically-conscious! Two words: Traffic Lights! Seriously, how does someone with no red/green differentiation deal with traffic lights at night?
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Post by class411 on Apr 17, 2018 18:03:31 GMT
Reading between the lines, I'm concluding that this is the first red/green deficient driver to be appointed under the disability discrimination act. Surely changes to the signalling ought to be made to accommodate this BEFORE such a person is placed in such a position. It's hardly fair otherwise. I’m assuming this is sarcasm? Poe's law at work here. There are so many barmy things going on you never know. True story: One of my sister's hotels has a garden that is only accessible via a very steep set of steps. She decided to have a ramp put in so that less able guests could enjoy the garden. The ramp is installed and much appreciated. Then the local council steps in and tells her that as it's a Grade 1 listed building she can't add the ramp. Who knew that listed building legislation trumped disability discrimination legislation?
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Post by class411 on Apr 17, 2018 16:31:55 GMT
Reading between the lines, I'm concluding that this is the first red/green deficient driver to be appointed under the disability discrimination act. Surely changes to the signalling ought to be made to accommodate this BEFORE such a person is placed in such a position. It's hardly fair otherwise. Is it really the case that discrimination law says that you have to employ someone who cannot, by the nature of the job, do the work safely? Does this mean that an airline must employ alcoholic pilots, provided they don't actually catch them trying to fly drunk? What about surgeons with acute Parkinson's disease? Epileptic high wire artists? I can well understand that the law insists you do not discriminate against someone who may need adaptations or feasible special considerations, but colour light signalling is pretty much fundamental to safe railway operation - even with ATO there are still times when the driver needs to be able to obey a red signal.
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Post by class411 on Apr 15, 2018 18:06:23 GMT
There's a goodeal(sic) to be said for that.
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Apr 15, 2018 8:27:13 GMT
Post by class411 on Apr 15, 2018 8:27:13 GMT
I always remember some drivers getting impatient with guards who took their time; they would "notch up" as a subtle hint to get a move on! I've checked and 'notch-up' is not in the terminology list. Sounds intriguing, though. Assuming he's not going to actually move the train, the only think I can think of is momentarily applying power against the brakes, which seems hard to believe. Or is it a signalling term?
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Post by class411 on Apr 15, 2018 8:21:25 GMT
How many amps are on LU I've heard in the past from one of the Tube documentaries that its 3000?. I'm afraid the question doesn't really make much sense, unless you mean very specifically: 'How many amps are available in on one section of track', and even there, the answer will be 'it varies'. I'll wait for an LU expert to give you a more detailed answer as I could only talk in generalities which might confuse the issue.
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Post by class411 on Apr 11, 2018 10:34:19 GMT
I'd forgotten about that. A bit poor that, as, looking at it, I was the one to mention RP.
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Post by class411 on Apr 11, 2018 9:17:39 GMT
How disappointing. I was hoping for something like Warrenby, on the Yorkshire coast, which in my youth had Plover Street, Teal St, Wild Duck Street and Decoy Street. Shades of Reggie Perrin.
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Post by class411 on Apr 10, 2018 17:51:20 GMT
33 1/3hz tracks were always bad especially with 40uf in the circuit you certainly knew about it uf = microfarad You talkin abart yer gramaphone, grandad? Seriously, the 33 1/3 sort of implies a vinyl record and whilst most record players would certainly include caps, I can't quite make the connection between the rotation speed and an electric shock. ETA, Pot here - after complaining about kettle a couple of minutes ago, I've just done it myself: 'caps' = capacitors. High voltage ones can give you a nasty belt and really big low voltage ones (as used in mainframe computer power supplies could literally (and, yes, I do mean literally) melt a screwdriver shank.
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Post by class411 on Apr 10, 2018 17:46:26 GMT
Honestly - people are not going to use a train because of the quality of the seats? I think the original comment was made in respect of IEPs, where driving is perhaps more of an option than it is for commuting. The added hassle of getting to Paddington/King's cross, plus possibly the need for a taxi at the other end, makes train less attractive anyway - poor seating may well be the last straw. What is an IEP? Checked the slang & abbreviations thread but it's not there. Even my mate google wasn't any help: Individual Education Programme? Internet Encyclopedia of Philosophy? Institutional Evaluation Programme?
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Post by class411 on Apr 10, 2018 7:52:55 GMT
Comfort is subjective. Always has been, always will be. I'm not a fan of deep sprung seats and find that many older seats cause me more problems than any modern seat. And that's coming from someone who has zero 'natural' cushioning... I find it depends on the length of journey. The seats on the old 4-SUB's were the most comfortable ever, if you were only using them for a few minutes. I hate to think what they'd do to your back if you were on them for an hour. The seats on the Electrostars (4 across versions) are superb, and remain comfortable for at least two hours. They are far more comfortable than any car seat in terms of having the ideal compromise between support and superficial comfort. I don't really pay much attention to seat comfort on underground trains but the S-Stock were no problem when I went from Ealing to Upminster.
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Post by class411 on Apr 8, 2018 14:23:55 GMT
Actually, the resistance between any two (external, skin covered) points of the human body is pretty much constant. This is because once the current is through the outer layer of the dermis it very quickly find some hot salty liquid (a.k.a. blood) that offers a very low resistance, and proceeds to flow along that. This is why you can kill yourself with a 9v battery if you connected one side to each arm through broken (and still bleeding) skin. Fortunately this is not something that's at all likely to happen by accident. And can we lay this "it's not the volts" myth to rest: The volts will kill you. Yes, you need enough current available (something that's not [or is] a problem with the mains, or a railway's traction supply), but you need the volts to drive it. So you actually need both the volts to drive the current and the available current, in order to do the damage. (The reason that people saying "it's the current that kills you" is annoying is that whilst in one sense it's a tautology, in another it's plain wrong, as having 1 billion amps available will do you no harm whatsoever if the available potential difference is only one volt.) And can you imagine the size of the cable? look at the size of cables on the National grid, then you'll realise why it runs at such high voltages of 400KV Well, you'd certainly need to reinforce the pylons. If I've got the calculation correct you'd need a conductor of ~150 2 metres cross section
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Post by class411 on Apr 8, 2018 14:16:52 GMT
having 1 billion amps available will do you no harm whatsoever if the available potential difference is only one volt.) Not sure what you mean by amps being "available". Sorry, I thought that was obvious. Any power source will only be able to supply a certain current (limited by, e.g. a fuse, or it's internal resistance). Thus 30 PP9's in series can't be used to satisfactorily power a 2kw electric fire, even for a few seconds. That seems to cover the bases. Indeed, but I meant 'available' in the sense that it could be supplied at all, not how long it could be supplied for. The billion amp figure was supposed to be hyperbolically illustrative, not a figure to be used in circuit calculations. Sorry, that's just plain wrong. Yes, the voltages are extremely high but the currents typically reach tens of thousands of amps.
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