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St Albans South - Works in 2016

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St Albans South - Works in 2016

Unread postby John Webb » Fri Jan 15, 2016 4:53 pm

2015 ended with a total of 2,394 visitors, just under 100 more than 2014's record 2,300+.

2016 got off to a flying start - late last year a visitor offered us some surplus items from his company in the Midlands. They were brought down in a hired van by two of our members on Tuesday 12th January and unloading commenced:
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We had to remove the items from the pallets to get them onto our site:
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But on Weds 13th the pallets were reused to put the signals on temporary display:
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(The signals on the left are our existing colour light signal demonstration set-up, for those who've not visited us.)
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Re: St Albans South - Works in 2016

Unread postby John Webb » Fri Jan 15, 2016 4:59 pm

We have the following:
LED GPL and 'R' display Theatre Indicator:
Image

Three and Four-aspect LED signals:
Image

LED Positions 4 and 5 Junction Indicators:
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Re: St Albans South - Works in 2016

Unread postby John Webb » Fri Jan 15, 2016 5:17 pm

A Position 1 JI (LED) and a Position 4 (bulb) JI:
Image

There are three other bulb-type JIs, I think 2 by position 1 and 1 by position 4. All the signals bear manufacturing dates from 2004-2008

We now have to plan how to display them permanently - probably at the edge of the concrete apron they are on at the moment, opposite to the existing CLS demo. The latter will possibly be rearranged by mounting the heads on short posts in the flower bed, raising them to eye-level and leaving more of the concrete free. But all very much in the early stages of planning at the moment. One problem may be the brightness of the LED signals at the short viewing range - but we'll sort that out once we've a better idea of how to position them.
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Re: St Albans South - Works in 2016

Unread postby Mike Hodgson » Fri Jan 15, 2016 7:16 pm

Good to see some more modern signals being preserved.

A couple of suggestions for your consideration ... are you going to wire them to the lever frame?
Or perhaps connect to some sort of automatic simulator cycling through the aspects (the model railway market has some cheap devices which could be used to control this).
You could consider wiring that 4-aspect head in parallel with and adjacent to a conventional head with 4 separate lamps so as to illustrate to the layman the similarities and the difference between the two types.

Richard Pike's JI does such a good job of illuminating the garden and his kitchen I have heard it referred to as "Luton Airport Landing Lights" - and that one has bulbs rather than LEDs. I appreciate your constraints about not pointing these things at the Main Line and that you also have to avoid any possible nuisance to other neighbours, but if you are able to strategically site a JI which is lit continuously during your opening hours, it may be good enough to act as a street light for your visitors. If the height of a JI makes that unsuitable, a double white aspect on a GPL might serve the same purpose.
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Re: St Albans South - Works in 2016

Unread postby John Webb » Fri Jan 15, 2016 9:27 pm

Mike Hodgson wrote:Good to see some more modern signals being preserved.
There was some debate among us as to whether we should or not, but we realised that just as the late 1970s CLSs we have were superseded by LED signals, the development of 'in-cab' signalling will in turn displace the LEDs.

Mike Hodgson wrote:A couple of suggestions for your consideration ... are you going to wire them to the lever frame?
Or perhaps connect to some sort of automatic simulator cycling through the aspects (the model railway market has some cheap devices which could be used to control this).
You could consider wiring that 4-aspect head in parallel with and adjacent to a conventional head with 4 separate lamps so as to illustrate to the layman the similarities and the difference between the two types.
No, they will not be wired up to the frame - as with the existing CLS demo, they will be connected to some form of sequencer. 'Flashing yellows' have already been mentioned! We expect they will be parallel to the present 4-aspect heads, so the difference should be easy to show.

Mike Hodgson wrote:Richard Pike's JI does such a good job of illuminating the garden and his kitchen I have heard it referred to as "Luton Airport Landing Lights" - and that one has bulbs rather than LEDs. I appreciate your constraints about not pointing these things at the Main Line and that you also have to avoid any possible nuisance to other neighbours, but if you are able to strategically site a JI which is lit continuously during your opening hours, it may be good enough to act as a street light for your visitors. If the height of a JI makes that unsuitable, a double white aspect on a GPL might serve the same purpose.
With the several duplicate JIs, I had started thinking about using one to illuminate the stairs - certainly the bottom section. As you say, we will need to be careful, but if pointing away from the railway, there should be no problem. There is a spare 4-aspect head on which we could mount the JI at about the right height.

The other problem common to all these signals will be to try and avoid using 110 volts - we prefer to stick to extra-low voltage (ie below 100V) if we can.
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Re: St Albans South - Works in 2016

Unread postby Mike Hodgson » Sat Jan 16, 2016 1:12 am

Yes, signal lenses are effectively focused quite well towards the train driver, and the lens hoods also help to restrict light from straying away from the direction the signal is facing.

Below 100v isn't quite the definition of Extra Low Voltage : the requirement is no more than 25v RMS from each conductor with respect to earth for AC, or no more than 60v for ripple-free DC. In practice most equipment described as ELV is actually 12v although some other voltages common in railway equipment can count as ELV, which could conceivably be a restriction your insurance might have stipulated for outdoor equipment.

If you find you do need to use 110v, you could use a "builder's transformer", as commonly used to run power tools on building sites. These are centre-tapped so you have 55v - 0 - 55v, the centre terminal being connected to earth for safety. This means you have a maximum of 55v to earth, so it's still not ELV. However at about a quarter of the voltage of the Live wire in your household mains, it is much safer and only slightly higher than the voltage on a telephone line. While this approach doesn't completely eliminate risk of electrocution, you are much less likely to do permanent injury with 55V to earth, although you could still suffer serious harm using 110V and no earth.

I should point out that although earthing in this way would be safer for your volunteers and visitors, it would be at variance with standard practice in railway signalling, and so it may not be appropriate if your installation is likely to be maintained by railway engineers expecting to find the standard circuitry they would find in a relay room. The reason the rail industry does it differently is to do with a consideration you don't have - safety of trains in circumstances involving multiple electrical faults, eg the 1954 derailment at Thirsk, in which a motor point unexpectedly moved as the train was closely approaching. Safety of trains is seen as more important than the risk of electric shocks to qualified technicians who are the only people who should be tinkering with signalling equipment.
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Re: St Albans South - Works in 2016

Unread postby John Webb » Sat Jan 16, 2016 8:06 pm

Mike - thanks for the info - I am aware of the use of earth-free 100V from my studies of signalling practice, although my experience is mainly with BS 7671 (The Wiring Regs). We are not under insurance compulsion to use ELV - it's a decision we took when we first started putting wires round the garden purely from a safety viewpoint for protection of our visitors, particularly the younger ones, and to a lesser extent ourselves. We already have a transformer with 100V output (floating) which we used for a short while on our first 4-aspect 1970s signal - but the 24V bulbs in that were too bright for close viewing; we suspect the same problem will arise with the new LED signals! But we'll sort that problem when we get to it.
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Re: St Albans South - Works in 2016

Unread postby Mike Hodgson » Sat Jan 16, 2016 9:31 pm

With 24v bulbs I would suggest you under-run them at something like 20v, both to alleviate the brightness problem, and for longer filament life, although I would not advocate under-running any 24v relays you might have.

The internal circuitry of LED lamps may be such that you can't reduce the brilliance anywhere near as easily. These signals are indeed bright when seen head on at close range; it is of course a design objective that trains drivers can see them, even in fog. They are much less conspicuous when viewed at an angle.
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Re: St Albans South - Works in 2016

Unread postby Bob Davies » Sat Jan 16, 2016 11:09 pm

John Webb wrote:Mike - thanks for the info - I am aware of the use of earth-free 100V from my studies of signalling practice, although my experience is mainly with BS 7671 (The Wiring Regs). We are not under insurance compulsion to use ELV - it's a decision we took when we first started putting wires round the garden purely from a safety viewpoint for protection of our visitors, particularly the younger ones, and to a lesser extent ourselves. We already have a transformer with 100V output (floating) which we used for a short while on our first 4-aspect 1970s signal - but the 24V bulbs in that were too bright for close viewing; we suspect the same problem will arise with the new LED signals! But we'll sort that problem when we get to it.

Surely, a '1970's' signal would have used 12v 24w double-filament 3-pin bulbs (SL35) so I am not sure where 24v comes in, or did you remove the 110/12v transformers from the signal head? A high-intensity PLJI from the same era would also have used SL35 bulbs although there were still plenty of older PLJI's around using SL33 110V 16w bulbs.
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Re: St Albans South - Works in 2016

Unread postby John Webb » Sun Jan 17, 2016 7:44 pm

Bob Davies wrote:Surely, a '1970's' signal would have used 12v 24w double-filament 3-pin bulbs (SL35) so I am not sure where 24v comes in, or did you remove the 110/12v transformers from the signal head? A high-intensity PLJI from the same era would also have used SL35 bulbs although there were still plenty of older PLJI's around using SL33 110V 16w bulbs.

Sorry - slip of the pen - I meant 24Watts! Been a busy weekend with a major exhibition we attended in St Albans and the necessary preparations for it, which was rather distracting.
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Re: St Albans South - Works in 2016

Unread postby John Webb » Thu Jan 21, 2016 2:40 pm

The exhibition at St Albans Arena went well - some 250 leaflets given out, 170 visitors to the box and several hundred pound's worth of sales between box and exhibition.

Yesterday we tried out some of the new LED signals received last week.
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This GPL is actually designed for 'elevated mounting' according to the internal label.

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GPL 'Off' and theatre lit.

The three aspect on Yellow:
Image

Time and dusk caught up with us before we could try out any other of the signals.

We expect to receive the 'Train Describer and track circuit' demonstration unit shortly from the NRM. I'll post pictures in due course.
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Re: St Albans South - Works in 2016

Unread postby John Webb » Sun Jan 24, 2016 9:24 pm

We were open again for this weekend for the former "St Albans Residents First" weekend, now called "Residents: Enjoy St Albans!". There were 373 visitors over the two days, and we're only 32 visitors off our 15,000th visitor since October 2008.

Next January will be quieter - the Chiltern Model Railway Association's annual show, held on the 16th/17th January, moves next year to Stevenage to a larger venue with better car parking, so we probably won't open the box during their show as we have done since 2009. And the "Residents: Enjoy St Albans!" weekend is expected to move to March to coincide with the end of "English Tourism Week" currently held in March. These changes will mean a rewrite of our leaflets during the year.
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Re: St Albans South - Works in 2016

Unread postby John Webb » Sun Jan 31, 2016 5:39 pm

Two weeks ago one of our Position 1 bulb-type JIs recently acquired was fitted to our fifth four-aspect head that had been on static display next to the stairs for several years, and moved across the path so that the signal is pointing at the stairs rather than the railway.
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(The Shunt Limit sign has had to be moved out of the corner of the two fences to a position where the 4-aspect signal wasn't hiding it.)

Last week I laid in some conduit to take power from the box to the signal and JI:
Image

I then started fitting LED bulbs similar to the ones we've used in our signal heads; this is the first trial:
Image

I'm very hopeful that once the JI has all 5 bulbs in, the bottom half of the stairs will become reasonably lit. Further pictures to follow when completed.
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Re: St Albans South - Works in 2016

Unread postby Richard Pike » Sun Jan 31, 2016 7:00 pm

Well there's a wrongside!
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Re: St Albans South - Works in 2016

Unread postby Signal-sighter » Sun Jan 31, 2016 8:44 pm

You have a good few thousand pounds worth of kit there. I am amazed you were offered these as they are entirely suitable for reuse on the big railway.
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