A new signal to me.

[royaloak]

Another way of doing it - presumably because the limited platform length at Penzance means that the cab often has to be very close to the signal http://www.railsigns.uk/photos/p_clsig2/pic_mcus.jpg 

 

Linky no worky, its a railsigns security thing.

[royaloak]

Is that to justify the risk or the rules though, because on the face of it it sounds like the type of absurd over-the-top situation that makes me roll my eyes at them. I appreciate that I'm not the person on the ground going up ladders so there's probably all sorts of practical stuff that I'm unaware of, and a long history of people falling off signals and getting hurt or worse. There were some pretty tall semaphore signals back in the day that I wouldn't have liked to climb unprotected on a windy day but I don't think anyone's gone for 50' tall colour lights!

They are removing the handrails on the front of our 150/2s to comply with working at height regs, if we need a new wiper blade the unit has to go onto the depot and staging has to be used, so a 5 minute 'do it on the platform while the driver changes ends' job is now a train cancelled do it on the depot job!

 

I agree that risk should be minimised but you can never eradicate it completely and taking on the jobs we do we accept that there will be some risk while carrying out our normal duties and H&S should be making our jobs easier not harder through having to erect staging (I wonder what the risk analysis is for that compared to leaning across from a station platform?) but it is getting to the stage where H&S is preventing the job getting done and that cant be right.

[HillsideDepot]

Another way of doing it - presumably because the limited platform length at Penzance means that the cab often has to be very close to the signal http://www.railsigns.uk/photos/p_clsig2/pic_mcus.jpg 

 

 

 

Linky no worky, its a railsigns security thing.

 

Apologies for the non-working link - here is my picture of the signal, albeit not as clear as the one I'd tried to use.

[TheSignalEngineer]

I wasnt having a 'pop' at you, sorry if you thought I was (I would say I was having a 'vent' in your general direction   ) and as you are on this forum you obviously have an interest that goes beyond the day job!

 

But signals are close to my heart (because getting them wrong could have serious repercussions about my ability to pay my mortgage) and these things just dont appear to have had any thought about the 'end user' in their design, for example, on 4 aspect heads the 2 lens are so much closer together they can blend in from a distance and when you go from 3 to 4 aspects it can be difficult to see if that first 4 aspect head is single or double yellow, something that never* happened with proper signals because the 2 yellow aspects are further apart than their modern equivalent.

 

* you should never say never because there is always an exception!

Multi-aspect heads although looking quite simple were a very complex  design. Based on 200 years of science and 100 years of experience.

The lens system itself is based on the Fresnel Biprism as used in lighthouses to give a powerful narrow (4^o) light beam which is visible from a long distance.

The positioning of the lampholder is critical to giving the best light. This is set to the optimum position for the main filament of the two-filament bulb. Although the position of the auxiliary filament is only about 3mm different an experienced eye can tell the difference in the light output from a particular signal.

The black space between the lenses on a double yellow aspect should be twice the diameter of the lens. At this spacing the two aspects will not merge except at an extremely long range.

Contrary to popular belief there is no reflector inside. This is to prevent phantom aspects produced by an external light source passing in through the lens and being reflected back. 

In my opinion VMS have never been properly tested in a railway environment to the extent that new equipment was tested in the past. The principles come from the road environment when signalling is not treated as being safety critical. How many times have you driven down a motorway and seen message boards and speed sogns with corrupted characters and flashing lights with one or more missing?

[Reorte]

I agree that risk should be minimised but you can never eradicate it completely and taking on the jobs we do we accept that there will be some risk while carrying out our normal duties and H&S should be making our jobs easier not harder through having to erect staging (I wonder what the risk analysis is for that compared to leaning across from a station platform?) but it is getting to the stage where H&S is preventing the job getting done and that cant be right.

I suppose the response to that would be "why do you accept that there will be some risk?" (although zero risk is impossible if you're going to do a job). And it's easy to see why we've gone down the path we have - you don't have to go back that far to get to a time where really horrible accidents would often be viewed with a "well, it's a risky job" attitude, and that's not something I think that anyone wants to go back to. It does all feel like it's gone too far in the other direction though, although since my job just involves sitting in an office perhaps I really shouldn't comment at all, I'm not the one having (or not) to go up ladders.

[Reorte]

Contrary to popular belief there is no reflector inside. This is to prevent phantom aspects produced by an external light source passing in through the lens and being reflected back. 

In my opinion VMS have never been properly tested in a railway environment to the extent that new equipment was tested in the past. The principles come from the road environment when signalling is not treated as being safety critical. How many times have you driven down a motorway and seen message boards and speed sogns with corrupted characters and flashing lights with one or more missing?

And LED traffic lights with really bright, glaring green phases... Road signalling could do with being a bit more tested too.

[The Stationmaster]

They are removing the handrails on the front of our 150/2s to comply with working at height regs, if we need a new wiper blade the unit has to go onto the depot and staging has to be used, so a 5 minute 'do it on the platform while the driver changes ends' job is now a train cancelled do it on the depot job!

 

I agree that risk should be minimised but you can never eradicate it completely and taking on the jobs we do we accept that there will be some risk while carrying out our normal duties and H&S should be making our jobs easier not harder through having to erect staging (I wonder what the risk analysis is for that compared to leaning across from a station platform?) but it is getting to the stage where H&S is preventing the job getting done and that cant be right.

 

One tip - don't ever confuse 'H&S' with common sense and doing the job properly or safely and, most important of all do not confuse 'H&S' with legal trade inspired back covering.  A lot of what is written into some procedures and the way companies work owes more to the latter than it does to carefully considered safety aids.

[The Stationmaster]

I suppose the response to that would be "why do you accept that there will be some risk?" (although zero risk is impossible if you're going to do a job). And it's easy to see why we've gone down the path we have - you don't have to go back that far to get to a time where really horrible accidents would often be viewed with a "well, it's a risky job" attitude, and that's not something I think that anyone wants to go back to. It does all feel like it's gone too far in the other direction though, although since my job just involves sitting in an office perhaps I really shouldn't comment at all, I'm not the one having (or not) to go up ladders.

The design of railway signals should not involve any inherent sort of risk at all.  Luminosity and colour temperature used to have to comply with strict standards in BR days and new designs were subject to extensive testing - e.g. the first pattern of LED head (which in many respects became the Dorman design) was tested for several years before being approved for wider use (it was a 'live' test and I have pictures of the signal concerned). Similarly the peculiar 'Mickey Mouse' signals were also subject to long term testing (albeit not normally live) with one in place on the Down Relief between Ebbw Jc and Cardiff Pengam for a long time.  Also the first fibre optic stencil indicator was on trial, in a live situation, fora  good time before wider installation progressed.

 

The new 'ultra-bright' LED signals appear not to have undergone such rigorous testing having seemingly appeared in numbers from a standing start and with an over 'bright' yellow to boot plus poor visibility from various angles.

[royaloak]

One tip - don't ever confuse 'H&S' with common sense and doing the job properly or safely and, most important of all do not confuse 'H&S' with legal trade inspired back covering.  A lot of what is written into some procedures and the way companies work owes more to the latter than it does to carefully considered safety aids.

I could never, ever confuse H&S with common sense, I am old enough to remember when most people had common sense, but now it isnt so 'common'any more.

 

I reckon 90% of H&S is purely to avoid prosecutions and nothing to do with safety itself!

[royaloak]

Apologies for the non-working link - here is my picture of the signal, albeit not as clear as the one I'd tried to use.

20141011_133740small.jpg

Thats the signal I was thinking of, Penzance platform 4, there is a very real chance that if a HST runs down towards the blocks the rear cab (which would become the front cab on departure) would be beside the signal hence the pigs ears.

 

Please also note the 'hot strip' in the top left of the signal as a cure for us losing sight of the very directional beam of the signal, all this type of LEDs have this because of the (supposed) non issue of us losing sight of the main part of the signal as we approach them plus the fact that if we are getting that close to them at a low speed it is normally because they are red, notice how the main part of the signal is all but impossible to see but the photographer is far enough away to get a decent photo.

[TheSignalEngineer]

I remember being involved in some trials with Fibre optics for signals. We put a banner signal in at Smethwick Rolfe Street in the early days. To get the signal bright enough to be seen in daylight it completely dazzled drivers in the dark. Another problem was the lamp output. The colour temperature of the halogen lamps used varied greatly and through the optical system what should have appeared white could show anything from pink to pale green in some instances.

[Edwin_m]

Thats the signal I was thinking of, Penzance platform 4, there is a very real chance that if a HST runs down towards the blocks the rear cab (which would become the front cab on departure) would be beside the signal hence the pigs ears.

There's one at Nottingham (platform 2) where there is a full-size co-acting signal mounted at 90 degrees, presumably to be visible through the  cab side window on a platform where a 4-car unit only just fits.  I hope they found some way of dimming it as I imagine it would be blinding at that range if full brightness. 

 

Interesting to see "railway is ignoring safety issues" and "health and safety gone mad" posts here in the same topic...

[TheSignalEngineer]

Looking at the Railway Group Standard on the requirements for product design and assessment of lineside signals there is minute detail about the shape, size and colour of a semaphore signal arm or Stop board but I recon I could get through the colour light spec with something I knocked up in my shed as long as I sprayed the case with a matt black rattle can..

[TheSignalEngineer]

 

Interesting to see "railway is ignoring safety issues" and "health and safety gone mad" posts here in the same topic...

"Operational" and "Occupational" Safety are two totally different things.

[Horsetan]

And LED traffic lights with really bright, glaring green phases... Road signalling could do with being a bit more tested too.

 

I've got no problem with LED traffic signals - I rather like them, and have a Peek Elite LED head in my collection, plus a full set of Swarco-Futurit "Futur3" LED inserts.

 

The French cottoned onto using LEDs for traffic signals years before we did. They also used spiral neon / fluorescent tubes as inserts as well. The whole history of French traffic signal design is fascinating in itself - they raised it to an art form and their signal heads were frequently unlike any other.

[Reorte]

Interesting to see "railway is ignoring safety issues" and "health and safety gone mad" posts here in the same topic...

It's entirely possible to have both at the same time.

[Reorte]

I've got no problem with LED traffic signals - I rather like them, and have a Peek Elite LED head in my collection, plus a full set of Swarco-Futurit "Futur3" LED inserts.

 

The French cottoned onto using LEDs for traffic signals years before we did. They also used spiral neon / fluorescent tubes as inserts as well. The whole history of French traffic signal design is fascinating in itself - they raised it to an art form and their signal heads were frequently unlike any other.

There are some I pass every day that are pretty unpleasant in the dark because they're so bright when on green. I don't have any issues with the idea of using LEDs - indeed, in general LED lighting is one of a rather limited number of modern developments that I like, but like a lot of technology it's not always applied well.

[Grovenor]

The black space between the lenses on a double yellow aspect should be twice the diameter of the lens.

But never has been! There is just space for the green between the two yellows, so one lens diameter plus two of the intervals between lenses which I would place at approx 1.25 times the diameter of the lens. The intervals vary a little between designs but roughly 1 inch with lens diameter of 8 3/8".

Regards

[ejstubbs]

The French cottoned onto using LEDs for traffic signals years before we did. They also used spiral neon / fluorescent tubes as inserts as well. The whole history of French traffic signal design is fascinating in itself - they raised it to an art form and their signal heads were frequently unlike any other.

 

The French also had (and may still have - I don't know as I haven't driven in France for some years) small repeaters for the main signal head on the same post, for the benefit of vehicles drawn up at the stop line.  I assume that this is the same idea as the things being referred to as "pig's ears" on this thread, going from the discussion about the pic of the Penzance signal.

 

For traffic signals, the small repeaters avoid having to put a full-sized repeater signal on the other side of a junction, as is usually done in the UK.  The French approach has a number of potential benefits IMO:

• lower cost;
• deters jumping the lights/"amber gambling" & jay-walking, since people can't so easily see what aspect conflicting traffic is being shown;
• avoids the disruption/danger caused by the occasional c*ckw*mble who gets confused and stops at the repeater, blocking part of the junction!  And yes, I have seen this happen more than once, and my gosh is it frustrating...

As for brightness issues, one would think that something could be done to adjust the the LEDs' brightness using a light sensor.  I realise that these things aren't 100% reliable; I know that the "automatic" headlights on my car sometimes come on for no readily explicable reason, but I would have thought that it would be easier to get such a system 'tuned' appropriately in a fixed location where sunlight and shade angles and the like can be predicted fairly well.  I know that some traffic lights have to have special shades and/or baffles to deal with problems like this and I'd be surprised if the same wasn't true of railway signals.

[Horsetan]

The French also had (and may still have - I don't know as I haven't driven in France for some years) small repeaters for the main signal head on the same post, for the benefit of vehicles drawn up at the stop line.  I assume that this is the same idea as the things being referred to as "pig's ears" ....

 

Yes they do, and the Belgians, Spanish, Algerians, and Moroccans use them as well. They've also been tried in Singapore.

 

Not sure whether the Scandinavians have them - didn't see any in Norway when I went there.

[phil-b259]

 

I've got no problem with LED traffic signals - I rather like them, and have a Peek Elite LED head in my collection, plus a full set of Swarco-Futurit "Futur3" LED inserts.

 

The French cottoned onto using LEDs for traffic signals years before we did. They also used spiral neon / fluorescent tubes as inserts as well. The whole history of French traffic signal design is fascinating in itself - they raised it to an art form and their signal heads were frequently unlike any other.

 

They have a video on their website if a level crossing across the Lyon ring road (6 lanes on the main carriageway plus another 6 on the parallel collector / distributor roads!)

 

Also shown here 2mins 30 sec in

 

Can't imagine the British letting such a thing occur - send the goods by road would be the response over here.

[Fat Controller]

They have a video on their website if a level crossing across the Lyon ring road (6 lanes on the main carriageway plus another 6 on the parallel collector / distributor roads!)

 

Also shown here 2mins 30 sec in

 

Can't imagine the British letting such a thing occur - send the goods by road would be the response over here.

The branch is only used once in the proverbial blue moon; my god-daughter was brought up around there (she lived on rue Prof Beauvisage when she was little), and I never saw any evidence of use. Lynne did see the crossing in use back in 1979 or 80, she was a passenger in an ambulance taking someone to Satolas airport which had to stop for a train. This wasn't the middle of the night, though, but mid-morning; in those days, the branch served several customers, so would have been in relatively regular use.

[The Stationmaster]

It's entirely possible to have both at the same time.

 

However it is a matter of getting one's priorities right.  It can also be interesting when one culture of safety (operational safety) comes up against the occupational safety situation of another culture and you are trying to satisfy two lots of requirements with a single, simple, Instruction.   It isn't always as easy as you might like to think when two very different ways of working things have to come together and you're trying to ensure two different safety cultures will both work as they need to.

 

The situation with railway signals is in my view very simple - they are there to protect operational safety and impose a separation between train and other trains/things etc.  Thus the important factor in designing them is to make sure they do that to a consistent standard and do it safely.  Designing access for maintenance comes second and if there is any conflict the operational safety angle should have precedence - leaving the occupational safety area ALARP, and not necessarily gold plated.

[RailWest]

The French also had (and may still have - I don't know as I haven't driven in France for some years) small repeaters for the main signal head on the same post, for the benefit of vehicles drawn up at the stop line.  I assume that this is the same idea as the things being referred to as "pig's ears" on this thread, going from the discussion about the pic of the Penzance signal.

 

For traffic signals, the small repeaters avoid having to put a full-sized repeater signal on the other side of a junction, as is usually done in the UK.  The French approach has a number of potential benefits IMO:

• lower cost;
• deters jumping the lights/"amber gambling" & jay-walking, since people can't so easily see what aspect conflicting traffic is being shown;
• avoids the disruption/danger caused by the occasional c*ckw*mble who gets confused and stops at the repeater, blocking part of the junction!  And yes, I have seen this happen more than once, and my gosh is it frustrating...

 

At the risk of going off railways for a moment....

 

I would agree with the above, I see too many examples of this. With my 'railway' hat on, I find it very odd that to have a situation where, if you are in a very slow moving line of traffic going across a very wide junction, then - whilst it is illegal to past the first signal that you come to when it is at red - if you pass it when it is green but it changes to red before you have reached the further 'repeater', then you just ignore that red.

 

However....there is one junction that I use frequently on a very busy road where there are two lanes at the approach to the lights. If the lights are at red, and you are stopped in the RH lane (which is just for 'straight ahead') at the front of the queue and there is a lorry stopped in the LH (turn left) lane, then you simply can not see the lights to your left. Without a repeater in front of you, then you would have no idea when the lights have turned to green. (You can't just move when the traffic on your left moves, as that has a separate filter.)

[TheSignalEngineer]

But never has been! There is just space for the green between the two yellows, so one lens diameter plus two of the intervals between lenses which I would place at approx 1.25 times the diameter of the lens. The intervals vary a little between designs but roughly 1 inch with lens diameter of 8 3/8".

Regards

I will stand corrected on that point Keith. The actual distance between lens centres on a traditional head is about 10". The spacing of double yellow aspects should be 5x lens aperture radius. That gives a space of about 12" between the inner edges of the lens bezels. My guess based on photos is that VMS doesn't match this. Can anyone supply the actual measurements please?