Variety of signals

[ryan125hst]

Does anyone know why there is such a mismatch of new signals on the network? Even along the same stretch of track there can be two or more different makes of new LED signal.

Let me explain: Thrumpton signal box has recently had an upgrade and a new £16 millon Wescad signalling system has been installed (a bit strange for an old mechanical signal box I know, but if you read this, it will all become clear. It looks like it is here to stay for another ten years!). As part of these works, Thrumpton has now taken over the area formally controlled by West Burton signal box. As well as this, I have observed a few infrastructure improvements as well. For example, the track on platform 3 has been replaced, and new concrete sleepers and ballast have been layed. Looking at the state of the track on platform 4 (oily, wooden sleepers and the ballast doesn't look great), it's probably only a matter of time before that is also replaced. As well as this, the signals between Retford and Worksop (and beyond) have been replaced, and, while I haven't been that way for a few years, I'm sure new signals have been installed in the Lincoln direction too.

New LED signals have been installed- the signal at the end of platform 3 has now gone and a new LED signal has been installed a little further along the track in the Sheffield direction. I am not against new signals being installed- yes, I was a bit shocked to see the signal mentioned had been removed, and the instantly responding LED's are a bit different to bulbs fading in and out, but they are a lot brighter and I'm sure most drivers prefer them as they are surely easier for them to see (can a driver confirm this?).

What I can't understand, however, is why there are two or three different types of signal on the same bit of track and installed during the same project. I have seen a few of these signals, by Unipart rail, both for aspect, as shown from page 6, and three aspect (see diagrams on page 8). However, around the Retford area, I have seen these Super-lightweight LED signals by VMS. In fact, if my memory of my journey to Chesterfield on the 8th February is correct, I'm sure there were some VMS signals between some of the (also new) Unipart signals.

So, two questions:

• What do you think of the VMS signals? I am not keen on them and much prefer those by Unipart. The Four aspect ones look good, and even the three aspect (shown from a single head if that makes sense) look good. In fact, I prefer the strange looking Integrated Lightweight Signal compared to the VMS ones. They look two thin and I'm not keen on the way the LED's display.
• Why is there such a variety of signals on the same track? There are both two and three aspect Unipart and three aspect VMS signals in areas that have been resignalled. When added to the semaphore signals in the Woodhouse area and the older BR filament lamp signals nearer to Sheffield, there are at least five different types of signal between Retford and Sheffield, and I'm fairly sure that the line speed is roughly 60mph throughout.

Finally, some photographs from flickr to illustrate my point (not my photos):

• Unipart signals at Chesterfield station: I like the look of these and think they are an ideal replacement for the BR filament signals. Sorry if you work for VMS, I just think Uniparts signals look more substantial. http://www.flickr.com/photos/dwbphotos/4528655968/in/photostream/
• The back of a VMS signal: http://farm8.staticflickr.com/7390/12310819945_86fcbc58ee.jpg
• A four aspect Unipart and a 3 aspect VMS in one location! http://farm8.staticflickr.com/7402/12310990433_0215cdc221.jpg
• Woodhouse Junction's semaphores- they are sill in use for now: http://www.flickr.com/photos/nottsexminer/6448431425/
• A classic three aspect Unipart signal: http://www.unipartdorman.co.uk/rail/rail/
• A VMS signal: http://www.rmweb.co.uk/community/uploads/monthly_11_2012/post-6662-0-79510800-1351891827.jpg
• Detailed photos of a VMS signal: http://www.rmweb.co.uk/community/index.php?/topic/63745-vms-lightweight-signals-cheap-and-cheerful/

I hope everything has made sense! A final question: What type of signal do drivers prefer?

Ryan

 

[GB]

LED signals are very bright but can easily dazzle the driver, particularly during wet weather or darkness. Despite their brightness, they have no penetration power during fog and can be more difficult to pick out than bulbs. Every driver I know hates them.

 

[455driver]

LED signals are very bright but can easily dazzle the driver, particularly during wet weather or darkness. Despite their brightness, they have no penetration power during fog and can be more difficult to pick out than bulbs. Every driver I know hates them.

You took the words out of my mouth!
But-

When NR replace the lamp in a normal signal head with a group of LEDs (so the light is still focused through the lens) we get the best of both worlds, NR save money and we get good penetration without going blind!
fnar fnar!

 

[rdeez]

Personally I have to say aesthetically, I like the VMS signals more! They're quite stylish. But...style isn't the point of a signal, so it comes down to reliability and legibility, and we won't know much about the former until they've been in use for a while, I suppose.

 

[MarkyT]

Personally I have to say aesthetically, I like the VMS signals more! They're quite stylish. But...style isn't the point of a signal, so it comes down to reliability and legibility, and we won't know much about the former until they've been in use for a while, I suppose.

The clever thing about the VMS system is the lightweight hinge down post assembly. This avoids the extra bulk and weight of access ladders and platforms and means simple straight posts can often be squeezed in at many sites where much more complex and expensive gantries or cantilevers would be required otherwise. Having been convinced many years ago that LEDs are the future for reliability and cost, I nevertheless admit a fondness for the good old fresnel lens and it's pleasing to see that some LED products retain or provide them.

 

[Cherry_Picker]

I much prefer LED signals, I think they are superior in every way to the old incandescent.

 

[455driver]

I much prefer LED signals, I think they are superior in every way to the old incandescent.

Seriously?

I find them blinding in the dark and next to useless in fog!

 

[JB25]

I like the fact when driving Caterham's and Tattenham's I can tell the next signal colour as the fog lights up the colour of it as they are bulb signals.

 

[455driver]

Wait until they are converted to LED heads, you wont see fu anything until you are about 20 feet away from them!

 

[Cherry_Picker]

Seriously?

I find them blinding in the dark and next to useless in fog!

Yeah, I much prefer them. We have a variety of them on the Chilterns too, the ones at the southern end are solid blocks of colour while the ones between Banbury and Leamington Spa are a bit fancier because they are angled in such a way where they appear to be solid blocks of colour from a distance but fade as you get closer leaving only an intense semi circle at the top of the signal (from 9 o'clock to 3 o'clock if you can imagine what I am describing) but all of them are great as far as I am concerned. There is a co acting one on LUL infrastructure on the down platform at Rickmansworth too, the incandescent signal is up on a post while the LED is almost down on the floor, it's about half the size of every other LED signal I've ever seen (in fact it almost looks like a toy) but it's still the one I use. I guess I prefer bold saturated colours. I've never once had a problem with finding them blinding.

 

[455driver]

Yeah, I much prefer them.

Fair enough!

the ones between Banbury and Leamington Spa are a bit fancier because they are angled in such a way where they appear to be solid blocks of colour from a distance but fade as you get closer leaving only an intense semi circle at the top of the signal (from 9 o'clock to 3 o'clock if you can imagine what I am describing)

Yes its there because the normal LEDs are almost invisible if looked at from an angle, the 'hotstrip' is to ensure the correct colour is clearly visible!

but all of them are great as far as I am concerned.

You are the first driver I have heard say that!

Do you have any 3 colour, single lens signals?
I think they are the worst!

 

[driver_m]

I'll give a bit of moral support to cherry picker here, I prefer LEDs too. I guess the WCML has every type at the moment and they're making the normal filaments look pretty poor if I'm honest.

 

[westcoaster]

I'll give a bit of moral support to cherry picker here, I prefer LEDs too. I guess the WCML has every type at the moment and they're making the normal filaments look pretty poor if I'm honest.

I like LED's over bulbs as well although the new ones at the south end of gatwick are odd they look like loads of bulbs in an LED style.

 

[455driver]

Are we all talking about the same type of LED head, the ones I hate are the ones which are either 3 colours in 1 or the ones that look like a proper 3 or 4 aspect head with a pack of LEDs visible as a load of dots.

The only ones I like are the ones which have the normal head (with filter on) and the lamp is simply replaced with an LED pack but from the front it looks like any other signal installed since the 1960s.

 

[Crossover]

Ah, this thread explains a lot of what I have seen recently. I first saw the VMS signals a couple of weeks ago on the East Suffolk Line, and have seen (and photted) those at Earlestown today. I agree they look stylish, but I find they appear a bit odd, especially with the "repeater" on the side as the main aspect goes invisible as you approach. I also agree as to the brightness, as in daylight stood on the platform, they can be blinding! (as an aside, I find the same issue with LED traffic lights on our roads, as at night, even with them dimmed, as I believe they do, they're still bright!)

I think the Unipart ones are more common, and I like the chunkiness of them, though some of the gantries I see them on (as new installs) are horrendously over-engineered!

 

[455driver]

(as an aside, I find the same issue with LED traffic lights on our roads, as at night, even with them dimmed, as I believe they do, they're still bright!)

Adding to this, if you think LED traffic lights are bright when they are dimmed, imagine if they stayed bright all the time?
Railway signals dont dim, they are extremely bright at night!

 

[Crossover]

Adding to this, if you think LED traffic lights are bright when they are dimmed, imagine if they stayed bright all the time?
Railway signals dont dim, they are extremely bright at night!

That may explain drivers wearing sunglasses in all weathers

I have noted this though - just tonight I was at Huddersfield staring straight into one as I was watching ensuing drama unfold on the platform :P

 

[starrymarkb]

They have those VMS ones between Salisbury and Feniton mounted on the original signal fittings. They look tiny on the enormous supports.

 

[ryan125hst]

The mixed response from drivers in interesting. Maybe it is to do with the type of LED signal installed?

455driver, which of these three LED signals do you prefer (and you can't answer neither! )

• A classic Unipart signal, as shown here at Chesterfield: http://www.flickr.com/photos/dwbphotos/4528655968/in/photostream/
• An ils signal by Uniparthttp://www.youtube.com/watch?v=RdBuIxyxwFU&list=UUBdWklqY3IVYZ4xAeh6uHPg&feature=c4-overview (It's a video as I've not been able to find a good photograph. I'll post it here if I find one. You will see, part way through the video, an example of a three aspect signal and a signal with route indication and subsidiary aspects).
• A VMS super lightweight signal. http://www.rmweb.co.uk/community/uploads/monthly_11_2012/post-6662-0-79510800-1351891827.jpg

 

[IrishDave]

There is in fact a fourth type of LED signal, but I've only seen it on the Chiltern main line thus far: it's got separate heads for each aspect, just like a signal with incandescent bulbs. See this picture: http://www.meadwaypark.co.uk/ChilternGX/Edit%2006018.jpg at Gerrards Cross. Not sure who they're made by.

 

[rebmcr]

it's got separate heads for each aspect

I'm surprised that's not mandatory — having different colours integrated in the same head sacrifices the position-light functionality and relies solely on colour-light. Seems like it's sacrificing the belt-and-braces redundancy for no particularly pressing reason.

 

[IrishDave]

I'm surprised that's not mandatory — having different colours integrated in the same head sacrifices the position-light functionality and relies solely on colour-light. Seems like it's sacrificing the belt-and-braces redundancy for no particularly pressing reason.

I have a vague memory that some of the earlier LED signal installations - Norton Bridge on the WCML between Stafford and Crewe in particular - the top head was green/yellow and the bottom head was red/yellow. But in later installations the top head was yellow only (and only used for double yellows) and the bottom head was green/yellow/red. It seems like the older idea would at least give some of the redundancy you mentioned - anyone know if I'm barking up the wrong tree or if that actually happened?

 

[GB]

I'm surprised that's not mandatory — having different colours integrated in the same head sacrifices the position-light functionality and relies solely on colour-light. Seems like it's sacrificing the belt-and-braces redundancy for no particularly pressing reason.

What do you mean by having different colour aspects in the same head sacrifices the position-light functionality?
--- old post above --- --- new post below ---

There is in fact a fourth type of LED signal, but I've only seen it on the Chiltern main line thus far: it's got separate heads for each aspect, just like a signal with incandescent bulbs. See this picture: http://www.meadwaypark.co.uk/ChilternGX/Edit%2006018.jpg at Gerrards Cross. Not sure who they're made by.

Pedantic mode enabled, surely we mean one signal head but separate apertures?

In any case, signals with one head, one aperture but multiple aspects are nothing new and have been around since the 60's.

 

[MarkyT]

With the Dorman products, there is a standard 3-colour 'searchlight' unit which shows all colours through a single common aperture. This suffices alone for where only a 3-aspect sequence is required. There is a second simpler yellow-only unit housed above this where a double yellow aspect is also required. The seachlight format is not new, it was a popular style in the early days of colour-light signalling with the colour determined by a relay-operated filter in front of a fixed white lamp, and there were still some such electro-mechanical examples surviving around the network at the time the first LED searchlights were being introduced.

 

[edwin_m]

there were still some such electro-mechanical examples surviving around the network at the time the first LED searchlights were being introduced.

I think there are still some at Clacton. There were three at Nottingham until re-siganlling last summer.

 

[waterboo]

Am I right to say that LED signals stops that issue of wrong colour interpretation, meaning that it stops the chance of a driver getting a red confused for yellow.

 

[Railsigns]

In any case, signals with one head, one aperture but multiple aspects are nothing new and have been around since the 60's.

Since the 1920s, in fact.
--- old post above --- --- new post below ---

I have a vague memory that some of the earlier LED signal installations - Norton Bridge on the WCML between Stafford and Crewe in particular - the top head was green/yellow and the bottom head was red/yellow.

The only LED signals in which one aperture shows red/yellow and the other aperture shows green/yellow are miniature tunnel signals. There are several of these on Thameslink.

 

[Southernrover]

I think there are still some at Clacton. There were three at Nottingham until re-siganlling last summer.

I used to drive on the Bakerloo line back in the early eighties and North of Queens Park we had searchlight type signals that rotated from yellow to green. Unfortunately they rotated via the red aspect as well.
Used to cause some bum twitching when on the approach as I recall.

 

[cjmillsnun]

What do you mean by having different colour aspects in the same head sacrifices the position-light functionality?

Exactly what he said.

The incandescent bulb signals have the lights in a fixed position for the most part. There are/were some searchlight signals, however apart from those exceptions, a driver could glance at a signal and even if the colour wasn't perfectly discernable, if they could see a lamp in a certain position in the head was lit, then they would know what the aspect was.

 

[GB]

I used to drive on the Bakerloo line back in the early eighties and North of Queens Park we had searchlight type signals that rotated from yellow to green. Unfortunately they rotated via the red aspect as well.
Used to cause some bum twitching when on the approach as I recall.

Similar as the ones that used to be on the GEML. If it cycled through the red to get to its next aspect it was enough to cause TPWS activations and COAs if the train was in exactly the right place at the right time!
--- old post above --- --- new post below ---

Exactly what he said.

The incandescent bulb signals have the lights in a fixed position for the most part. There are/were some searchlight signals, however apart from those exceptions, a driver could glance at a signal and even if the colour wasn't perfectly discernable, if they could see a lamp in a certain position in the head was lit, then they would know what the aspect was.

Thats fair enough but it could have been explained a tad bit better. In my mind saying "position-light" in a thread about signals can refer to something else.