Traffic Movements at Sedgeley Junction 1962-1963 (Part 3)

Previous part.

Sedgeley Jn. Sat 22th December 1962

Night work on the bank!

Some amateur sound recordings were made on an EMI tape. I'm not sure whether they have survived.

(1) Shortly after midnight, the tanks for Cardiff struggle up the bank behind the usual Standard Class 9, making poor going after stopping at Great Bridge for water. This is 4V30 10.38 p.m. Empties from Soho Pool to Cardiff Bute Dock. It was always good to see a '9F' at work and sometimes, given a clear run, the driver would really "go for it" up the bank - but not on this occasion.
(2) T65 follows up “37 and Stourbridge”. 48762 is on the front and the Banker is 48335 off T63, dragging a Western brake van. Dudley’s taken him up the loop and the alert Guard in the Western brake has turned his one sidelight to white before he passes the box. Freight trains, of course, normally carried one red tail lamp and two red side lamps. If the train had passed to a parallel line (such as here, up the Third Line) the lamp nearest the main line would be turned to white, so as not to 'spook' a following train on the main line.
(3) Later, T63 comes down, engine propelling the brake with two white sidelights now acting as headlamps. (Not on tape).
(4) Empties from Round Oak to Norton Jn. roll downhill behind 48713 (mis-described in the ‘Is Line Clear?’). (Not on tape). Different classes of freight train had different 'Is Line Clear?' codes (such as '3', '3-1-1', '1-4', '4-1').
(5) The ‘Gloucesters’ hurl themselves downhill at a frightening page, behind a Fowler ‘4F’ that makes a terrible din with its motion shaking at such speed. (Not on tape).
(6) Next, a Stourbridge – Bescot train rumbles past with steel, slack, coke and an L.M.R. Brake with an ‘8F’ in charge. This would be 8M40, booked 11.25 p.m. from Stourbridge.
(7) Following, and almost ‘slacked’, a ‘Class 9’, burning up the brake blocks on twenty long-wheelbase tank wagons. 5M71, the 6.10 p.m. Cardiff Bute Dock to Soho Pool (loaded).
(8) Next, the ‘Cuckoo’ Eckington – Round Oak reported as “24 equal to 36 for Square Elm; I mean Round Oak” – 9V03 with 48189 on the front and 48766 pounding away at the rear (on tape). Even in the middle of the night, the gag about 'Square Elm/Round Oak' is trotted out. A train like this, working hard, with the glow from the engine fireboxes lighting the scene provided a wonderful experience.
(9) The Down Light Engine is stopped 6 minutes. The friendly fireman says the engine is T32. Horsley Fields Junction was closed at night, so the block section was Sedgeley Junction - Great Bridge. If Great Bridge was "doing a shunt", he often had to refuse an offered down train for a few minutes.
(10) T65, turned, is stopped 2 minutes returning downhill with his brake.
(11) The Up ‘Western’ goes Up the Loop to get out of the way of the Derby Parcels. Train engine and banker are Class 8s. Banker is reputedly T54 and without a tail lamp showing. (on tape).
(12) Down engine is 48402 tender first with an LMS brake van, to work WR4 back to the Western.
(13) The Derby reputedly has an open door and we are to stop him. 3V13 with D103 on the front. Tom goes down to examine but finds nothing. The long train restarting is on tape.
(14) WR4 comes up without a banker. 47 sticks. We get him moving.
(15) The Parcels engine clanks behind.

That was the end of the 'Night Shift'. Before I leave the box, Dudleyport says there’s a fishplate broken and the Up Line is blocked, necessitating diversions.

Sedgeley Jn. Mon 24th December 1962

(1) Up parcels is 3 full brakes and a 4-wheel van.
(2) Then first up ‘Western’; Leamington.
(3) T39 is reported with 11 wagons (50 pigs) for Palethorpes. When the train arrives, it's 44910 on 12 (!) cattle wagons and an LMR brake.
(4) Dudley cannot accept the following Walsall for a minute because his home is sticking off. The Walsall is two twinsets.
(5) The Engine and Brake is out of Palethorpes' at 8.42 a.m. and stands on the Up Main until the Down Walsall has passed, still with 4-cars. The Guard off the EBV signs the book.
(6) The 9.0 a.m. Down is a single-coach diesel and the pigs are already going to the factory, prior to slaughter.
(7) 46430 goes tender-first to Dudleyport for another parcels.
(8) Up Walsall at 9.15 is a twinset and goes Down a few minutes later with the driver (9) Gets busy as the Parcels goes Up from The Port with a 4-wheel van, full brake, 4-wheel van, full brake and an ER full brake.
(10) T39 charges Up to Dudley with ”11 and the brake”, coal, one Plate wagon, open wagons and vans.
(11) Meanwhile, a ‘4-1’ approaches on the Down - 8M37 with a Class 8 and the usual tubes, scrap, bars on Plate wagons and coke.
(12) ’312’ comes off the Dudleyport branch; 42659 bunker first with 3 Palethorpes vans, 6-wheel, 8-wheel, 6-wheel.
(13) Ten o’clock down is the single-coach Western diesel with the driver wrapped up in an overcoat and flat hat.
(14) The parcels goes down to Dudleyport High Level with 3 bogie vehicles.
(15) Up ‘Western’ and Down Walsall pass.
(16) ‘312’ has been waiting to come out of Palethorpes' since 10.8 a.m. Eventually, we wiggle ‘312’ out to stand on the Up Main outside the box. Then, by setting the road to the Up Loop, we can accept 47. Finally, ‘312’ departs light engine for Bloomfield Junction having waited 16 minutes all told.
(17) Once '312' has departed, we get the road for 47 up the Main. - 44805 with Pallet (concrete), sheeted open wagons,open wagons, empty mineral wagons, a loaded ‘Trestrol’, 4-wheel vans, eight Midland Tar Distillers tanks and a banker.
(18) T65 follows Up with 20 mixed wagons. The banker is 45180 – must be T63!
(19) At 10.55, 46430 drags a WR bogie van and a BG (labelled Parcels Mails Kilburn) to Dudley at good speed. Soon the parcels engine returns on the down, Light Engine for Bescot MPD.
(20) Up ‘Western’ precedes the Walsall.
(21) Dudley offers a ‘1-3-1’ and gives a nice ‘2’. Parcels goes down and Walsall comes Up.
(22) Down EBV is T47 returning.
(23) Down Walsall at 1.16 p.m. has the Guard’s Door swinging in. The Dudleyport Inspector is asked to check and Horsley Fields box is is advised.

That was the end of my 'early turn'.

Traffic Movements at Sedgeley Junction 1962-1963 (Part 2)

As described in an earlier post, you can find the passenger timings here and the freight timings here. The original notes appear in italics with minimal editing, followed by my recent comments attempting clarification. The numbers in brackets have been added to assist in locating entries. Let's dive straight in on a short evening session.

Sedgeley Jn. Sat 8th December 1962

(1) Up 'Western' is a ‘Prairie’ and 4 corridor stock at 6.15 p.m. The railways might have been Nationalised but most railwaymen retained their previous tribal affiliations, so passenger trains to and from the Western Region at Horsley Fields Junction were usually referred to as 'Westerns', like some alien intruder. The LMR service between Walsall and Dudley was referred to as 'the local' or (irrespective of direction) 'the Walsall'. Almost all regular passenger workings through Sedgeley Junction were operated by DMU, but there was a commuter working into Snow Hill from Brettel Lane in the morning with a return in the evening which was steam-hauled. I never quite got used to the sight of a Swindon 'Big Prairie' on what I thought of as an LMS route.
(2) Up 'Western' in at 7.29 p.m. and Horsley Fields “closes”. This local from Snow Hill was a DMU. The quotation marks around 'closes' suggests that this was a case of the signalman slipping out of the box for a while unofficially.
(3) Later, Dudley “closes” saying “If you get any rubbish, sweep it up the Third Line”. Again, this is an informal closure and we are being encouraged to put any up train which should appear on the Up Loop without obtaining a 'Line Clear'. Since there were no block controls on the signals at Sedgeley Junction, such unofficial working was possible.

Sedgeley Jn. Sat 15th December 1962

(1) The first two down 'Westerns' are ‘Swindon’ 3-sets.
(2) The Walsall up at 7.33, down at 7.43 is a Met-Camm twin-set DMU.
(3) Up parcels at 7.45 is a LMR ‘Weasel’. 'Weasel' is a bit of local humour -rhyming slang for a 'diesel' - actually a DPU.
(4) T47 for Stourbridge is refused up the Loop, so goes Up Main with an 8F, holding up the Dudleyport dead slow. The Down Parcels is held 7 minutes, then run off the Local, holding the down 'Western'. It's around 8.00 a.m. Once T47 has passed the 'Clearance Point' on the Up Main (a quarter of a mile beyond our Up Home), we can let the passenger train approach from Dudleyport. T47 has to clear Dudley East before he can give 'Line Clear' for the passenger and we can pull off our signal.
(5) T39 up is a ‘Black 5’ facing Dudley.
(6) Down LE is the engine off ‘222’ (9V03) – an 8F facing Bescot (not the banker returning downhill as first thought). Note the use of both the 'old' trip number (222) and 'new' four-character reporting number (9V03).
(7) The Up Walsall at 9.0 a.m. is a ‘Gloucester’ unit. No sign of the Metro-Camm.
(8) The Parcels follows up, engine facing Dudley with four 4-wheel vans and the usual bogie vehicle. The Parcels is almost stopped, waiting for the road, and has trouble getting away.
(9) 8M37 on the down is a Class 8, sheeted wagons, odd metal and coke. The 8.25 a.m. Stourbridge - Bescot.
(10) T39 to Dudleyport follows the local. ‘Black 5’ tender first, two vans, 16-ton mineral wagon with scrap and a B.R. brake. Having dropped the two vans at Dudleyport, he returns propelling the scrap and brake, stops on the Up Main while we get the road and pull the crossover, then departs for Great Bridge.
(11) Control informs us that T47’s engine is returning to Great Bridge with his guard, to work a second train onto the Western before finally loading back. Birmingham Traffic Control both issued information and collected details of how trains were running. Control was usually referred to, ironically, as the "College" (as in "College of Knowledge")
(12) The Up Walsall at 10.09 is the ‘Gloucester’ unit.
(13) The Down Parcels is the 2-6-0 tender first with his bogie van, having dropped the 4-wheelers. The Guard is on the footplate, drinking tea!
(14) The Down Walsall is the ‘Gloucester’ unit.
(15) The Up at 10.40 is ‘phoned through as “T63 with 14 Dudleys”.
(16) The Up Parcels following is two 4-wheel vans and a bogie van. When he returns on the Down, he stops to deliver a new kettle for the box!
(17) T63, returning to Bescot, follows the Parcels and is just slowed as we wait for Horsely Fields to "Knock Out" for the Parcels. Giving 'Train Out of Section' was usually called "Knocking Out".
(18) Control says “65 is running and loading back with Pools to Norton Junction”. 9T65 comes up with an ‘8F’ and T63 banking. He goes into the Up Loop because he’s right in front of the Up 'Western'.
(19) Down light engine is off the Parcels (?)
(20) The ‘1-4’ on the Down has six and the brake. Control says “It’s 8M39 with 63 behind”.
(21) No sign of T47 as yet. Great Bridge have a special and WR1 (8V04), we’re informed.
(22) At last, T47 comes Down with a long train of empties.
(23) WR1 comes up with a banker and is taken Up the Main by Dudley. The load is 34 equal to 40 for Stourport. It’s 16-ton mineral wagons with power station slack.
(24) Now, the plan is for T35 to work the Great Bridge – Stourbridge Special, instead of T47.
(25) The Up 'Western' at '39 is held for a minute at our Home, while WR1 clears.
(26> The Great Bridge – Stourbridge ‘Special’ comes up, T35’s engine on the front, “Equal to 40 of coal” and T63 banking.
(27) The 2.0 p.m. Down 'Western' is augmented to two 3-car sets.
(28) T65 returns to home metals, the ‘8F’ hustling a double-braked train of empties to Norton Junction.
(29) T65 passes WR2 (8V06) on the Up, laboriously dragging "37 equal to 40" of coal and slack for Stourport.
(30) The following parcels from Walsall comes to a stand while Dudley is getting rid of WR2. It’s a grimy Standard 2-6-0 with an ER standard bogie parcels vehicle and a long wheelbase ‘Insul-Fish’ labelled ‘PARCEL MAILS’.
(31) T63 comes down with 44840, 3 vans and a BR Brake for Bescot.
(32) The driver on the Walsall Local is now quite friendly, exchanging greetings each time he passes.
(33) The parcels returns Down but we’re not sure where he’s for. We pull off for Walsall and away he goes with the ER bogie parcels van, having left the ‘Insul-Fish’ at Dudley.
(34) When we do get the expected Dudleyport Parcels, it’s the DMU off the ‘Walsall Local’ piled high with mailbags.

Traffic Movements at Sedgeley Junction 1962-1963 (Part 1)

There are earlier posts about Sedgeley Junction:-
14-Feb-2008
19-Jun-2009

We're attempting to reconstruct events over 47 years ago, so personal memory is a rather unreliable guide.

Working Time Tables of the period are a valuable starting point and there's some information linked to a post on Railway Working Time Tables.

Completed signal box Train Register books can give a mass of information but I have none. What I did have back then was my own Train Register book in which I copied the details from the official Train Register each time I was unofficially working the box. The 'Remarks' column would have explanatory notes to clarify what was going on. Tragically, this book is missing.

I also had a series of notebooks in which I would write more detailed explanations of the movements. Spurred by the interest of my friend Phil, I've recently located one of these notebooks (written with a fountain pen), covering my visits to Sedgeley Junction between December 1962 and June 1963. The notes frequently refer to times in the Train Register (which we don't have) so interpreting these notes is not straightforward but, putting together the Working Time Table pages and these notes, we'll get a better picture of events.

A major contribution has been made by Mike Hollick, who had already produced a 'Sedgeley Junction WTT Simplifier' for the period of interest. He has kindly given permission for this to be incorporated in the work.

So, all I have to do now is transcribe the notebook and write an intelligible description of the movements. Watch this space.

You can find all my posts describing Traffic Movements on the South Stafford Line and the Stour Valley Line in the steam era here.

[Link to all 'Traffic Movements' posts added 10-Nov-2015]

Railway Working Time Tables

A typical timetable page: Weekday passenger workings from Dudley to Rugeley and Burton-on-Trent

Sooner or later, most railway enthusiasts gain an interest in Working Time Tables (WTT). These are the non-public time tables that regulate the movement of both passenger and freight trains. I've collected a few different timetables from the late '50s or more recent periods, mainly covering the West Midlands.

It's a major task to copy these timetables and make them available for general study, but I've made a small start and will extend this as possible. I was finally spurred into action by the Slideshow at Brewood Hall. A number of my friends have an interest in the South Stafford Line, so I decided to start with the timetable pages covering this section. I also located one of my lost notebooks describing movements at Sedgeley Junction in late 1962 and 1963, so this determined the required date of the timetables. The link below will take you to the freight timings for the preceding period (I don't have a copy of the timetable for exactly the right period) and the passenger timings for the correct period.

Alternately, you can view these two Abstracts on the 'Scribd' document site, where you can view, print, or download in 'PDF' format. The links are below:-

The passenger timings are here.

The freight timings are here.

My own other area of interest is the Stour Valley Line, in particular the section from Dudley Port to Wolverhampton and I've now made the 1962/1963 Passenger Working Time Table available as two documents, one for Down trains, one for Up trains. These are also on 'Scribd':-

Down trains here.

Up trains here.

[Stour Valley Timetable Pages added 3-Mar-2010]

Slideshow at Brewood Hall

L to R: John, Phil, Keith, Ian, Mike, Natalie

I have made a number of friends through people getting in touch after reading posts about my recollections of the steam railway era. Recently, my friend Phil arranged for Keith to give a slideshow on 12th February 2010 to a small group of interested people. Keith presented a collection of 35mm slides he has recently acquired depicting steam/diesel/electric traction dating mainly from the 1960s onwards taken in the West Midlands. Present were Natalie, Keith, Phil, Mike, Ian, John and Jan.

All the slides were of great interest but I can't resist showing below a personal favourite (re-photographed from the screen). The original was taken from Tipton Owen Street signal box on a murky day and shows a 'Jubilee' on a down express passing the goods shed.

Later in the evening, Ian used his laptop computer to show some of his photographs of Norton Junction and the South Stafford Line. Jan had provided a computer projector which worked perfectly earlier in the evening but (of course) decided to fail when re-connected to Ian's computer, so everybody congregated around the laptop.

Ian showing some of his collection

The evening was a good opportunity to discuss arcane matters of mutual interest including signalling, working timetables and our lost railway infrastructure.

There's a small collection of pictures here.

Progress on Harvesting at Ty Gwyn

The Forwarder at work collecting Logs

Earlier reports 11th November 2009 and 8th December 2009 outlined the start of timber extraction at the Ty Gwyn woodland. December 2009 and January 2010 brought extremely hard winter conditions to many parts of Britain and production was held up by heavy icing on the steep access road.

I made a further visit on the 11th February 2010 to meet the Forester now responsible for the plantation, Rob MacCurrach, and look at the work in hand. Using modern techniques, only three people are engaged in timber extraction - the Harvester driver, the Forwarder driver and the Road Haulage driver. The Forwarder was working near the loading point and Rob was able to discuss progress with the driver.

The Timber Truck parks alongside the stacked logs, prior to loading using the on-board timber crane

The empty Timber Truck arrived after a few minutes - a huge 'Scania' 6-wheel tractor with a 6-wheel articulated self-loading timber trailer. One axle on the tractor and trailer was jacked-up, so that it was operating as an 8-wheel rig.

Rob and I then walked to to where the Harvester was being operated by Peter. I learned that five different types of log were being produced (according to diameter and cut length) plus occasional 'specials' requested from the Mill receiving the timber.

Detail of the H73e Harvester Head

The Harvester is fitted with the Ponsee 'H73e' Harvester Head (see data sheet) which can handle trunks up to 730mm diameter. It's amazing to watch the Harvester at work. In around a minute, a mature Sitka can be felled, de-limbed, cut into the required lengths and neatly stacked for later collection by the Forwarder.

Pictures showing the Harvesting operation are here.

Princes End Electrical Controls (Part 5)

Previous parts:-
Part 1 Introduction: Drawings.
Part 2 Relay room: cable terminations, relay rack and power supplies.
Part 3 Colour Light Signal 6: Control
Part 4 Colour Light Signal 6: Lighting and Indication
Working the box.

Simplified and approximate diagram. Clicking on any diagram displays a higher-resolution version which can be downloaded or printed

Introduction:

Parts 3 & 4 of this series described colour light signal 6. This time, we'll look at the relay circuits on part of Sheet 2 of the Contractor's Drawings, titled '19 Signal Selection, Control, Lighting & Indication Circuits'. Some of the principles we've already introduced when we looked at signal 6 in Parts 3 and 4 but this time we need to consider Approach Locking and Route Release.

A train proceeding in the Up Direction, after passing the last colour light signal controlled by Wolverhampton Power Box approached Princes End signal 19, a 3-aspect colour light. Lever 19 controlled the change from Red to Single Yellow then the aspect of the next signal (semaphore signal 18, giving access to the single line to Wednesbury) controlled the change from Single Yellow to Green.

Approach Locking and Route Release:

On plain double track line, trains follow one another in the same direction. The main risk is a train running into the rear of a preceding train. Ensuring that the line is clear to the next red signal, plus an extra overlap distance, before a train is allowed to proceed provides the necessary safety.

But where there are junctions, there is greater chance of conflict between two moving trains and additional safeguards are provided. At Princes End, double track became single so the potential conflict was between an Up train overrunning signals 19 and 18 and a Down train leaving the single line. The need for Approach Locking on signal 19 is based on the assumption that, having cleared signal 19 for an approaching Up train, the signalman may replace it (accidentally or in an emergency) before the train has passed the signal. Depending on the position of the train when the signal goes back to Red, the driver might not be able to stop before the signal. With purely mechanical interlocking, once the signalman had replaced lever 19, he would immediately be able to clear the signals for a train leaving the single line, creating the risk of an accident if the Up train was unable to stop. Approach Locking mitigates this risk using relays and a timer which still allowed the signalman to place signal 19 at danger in an emergency but enforced a suitable time delay before signals could be cleared for another movement.

Approach Release:

If the signalman wanted to clear signal 19 to allow a train to approach but was not in a position to clear signal 18 giving access to the single line, it was important to prevent the train from approaching at speed. In mechanical days, this was achieved by keeping a signal at danger until the train was close to it, called 'bringing a train under control'. With electrical locking, as described here, this was achieved by preventing signal 19 from clearing until track circuit 462 had been occupied for a suitable time.

Timer Relay:

The controls at Princes End used the Westinghouse 'PTT1' Thermal Timer for route release and approach release. This used the principle that if two dissimilar metals are welded together in the form of a strip and then heated, the strip will bend due to the differing expansion of the two metals. Two electrical contacts were placed so that a circuit was made to one contact at room temperature (the 'COLD' contact) and to the other when hot (the 'HOT' contact). An insulated coil of wire was wrapped around the bimetal strip to heat the strip when required. The time period was altered by adjusting the position of the 'HOT' contact. A slow-to-release relay and two diodes were placed in the same case as the timing device. When the 'HOT' contact closed, the slow-to-release relay energised and latched over a 'stick' contact. A contact on the 'slow to release' relay disconnected the heater coil so that the bimetal strip cooled. A second relay externally normally formed part of the timer circuit. This second relay was used to prove that the 'COLD' contact was closed before timing started and re-closed at the end of the timing. The diodes were suppression or commutating diodes wired across the coils of the internal and external relays to minimise arcing on the contacts of the Thermal Timer.

Colour Light Signal 19 Control:

Here's the circuitry controlling signal 19:-

Because Approach Locking is provided on signal 19, the first stage is to 'prove the route' by relay '19UCR' (19 route proving relay) in the relay room.

19UCR relay:

A number of conditions must be satisfied for '19UCR' to energise:-
- Track circuit 463 must be clear proving that the line is clear to signal 18. A contact on '463TS' stick relay is used, to prove that lever 18 has been replaced after the previous train.
- Track circuit 464 beyond signal 18 must be clear, to provide an overlap.
- Either a single line token must have been obtained and signal 18 cleared OR the Approach Release circuits must have brought the train under control.
- The signalman must have reversed lever 19.

(There's also a lock proving contact '19LCC' included but at present I'm puzzled by this).

So, if the signalman has 'got the road' and reversed levers 19 and 18 with clear track circuits, '19UCR' will operate immediately. If the signalman has not 'got the road', provided the two track circuits beyond signal 19 are clear and lever 19 is reverse, '19UCR' will operate when track 462 has been occupied for long enough for '462TJR' and '462TS' to operate (we'll look at the detail of this timing circuit shortly).

Control of Signal Aspect:

Two relays (in Location Case PE2/2 adjacent to signal 19) directly control the signal aspect:-
- '19HR': When released, the signal displays Red, when energised, the signal displays a Yellow (or Green).
- '19DR' When energised, '19DR' produces a Green.

The detailed controls for these two relays are shown below.

19HR relay:

'19HR' is fed with 50 volts from the relay room 'Double Cut' as follows:-
- '19AJS' (signal 19 Approach Timing Stick Relay) must be energised.
- '19AJR' (signal 19 Approach Timing Relay) must be energised.
- '19ALR' (signal 19 Approach Locking Relay) must be released.
- '19UCR' (signal 19 Route Proving Relay described above) must be energised.

19DR relay:

'19HR' is fed with 50 volts from the relay room 'Double Cut'as follows:-
- '19(RB) Circuit Controller in the signal box
- '19HR' in location case PE2/2.
- '19H1PR' in location case PE2/2.

Colour Light Signal 19 Indication:

Latching relay '19GCR' in the relay room provides indication of the signal in a similar way to the indication of signal 6, already described in Part 3.

463TS:

As soon as the train passes signal 19, track circuit 463 becomes occupied. '463T1PR' releases and, in turn, '463TS' and '19UCR' release, replacing signal 19 to danger. Even when track 463 clears, '463TS' will not operate until the signalman replaces lever 19 to 'normal', when '19(NA)' circuit controller will energise '463TS'.

3-aspect signal head:

Detail of 3-aspect signal head

The diagram above details the actual 3-aspect signal head. Details are similar to the 4-aspect signal head already described in Part 4 of this series.

Signal 19 Lighting and Filament Failure Indication:

19 Signal Lighting and Filament Failure

The terminals on the right hand side of this diagram connect to the signal head (see Fig. 8 above). The lighting is derived from a 110 volt a.c. supply in the location case adjacent to the signal (BX110 and NX110). The arrangements are similar to those for signal 6, already described in Part 4 of this series.

19 R/H/D ECR:

This relay will always be energised if one of the three main filaments or one of the three auxiliary filaments is drawing current. The circuit is similar to that for signal 6, already described in Part 4 of this series.

19 EC1PS (M):

This relay indicates failure of any of the main filaments to the signalman. The circuit is similar to that for signal 6, already described in Part 4 of this series.

Approach Control Timing Circuits:

19 Approach Control Timing Circuits

Both timing circuits above use the 'PTT1' Timer Relay. The upper circuit details the route release whereby, if signal 19 was prematurely replaced by the signalman, an electric lock prevented the lever from being placed fully normal (allowing another movement to be set-up) until after a suitable delay. The lower circuit shows the approach release circuit which delayed the clearance of signal 19 if the next signal (signal 18) was not 'off'.

19AJR:

'19AJR' (19 Approach Timing Relay) was energised provided that the 'COLD' contact of timer relay '19AJS' was closed. So '19AJR' released at the start of timing and a normally closed contact was used in the feed to '19AJS' coil which energised when the 'HOT' contact was made. A contact on '19AJS' disconnected the heating element so that, at the end of the cooling cycle, the 'COLD' contact was made, re-energising '19AJR'.

19AJS:

'19AJS' is fed with 50 volts from the relay room on pin 12 to initiate the timing sequence provided the following conditions are met:-
- '19UCR' released. This is the case if the signalman is attempting to replace lever 19 to 'normal'.
- '463T1PR' operated. The track immediately beyond signal 19 must be clear.
- '19(B)' circuit controller must be closed. This is the case if the signalman is attempting to replace lever 19 to 'normal'. The electric lock will prevent the lever from being fully replaced until Route Release has been obtained.
- '19JN' (19 Timer Manual Switch) must be closed. This is the case if the switch on the Block Shelf in the signalbox is not operated.

When 50 volts is applied to pin 12 of '19AJS', power is applied to the heating element through normally closed contacts on '19AJS' and '19ALS' which should both be released. After the heating cycle, the 'HOT' contact closes, applying power to the coil of '19AJS' (via the normally closed contact of '19AJR'). A contact on '19AJS' disconnects power from the heater element but '19AJS' remains energised over its 'stick' contact, as long as '19ALS' remains released. At the end of the cooling cycle, the 'COLD' contact closes and '19AJR' re-energises. Now both '19AJS' and '19AJR' are energised, 50 volts is fed to the coil of '19ALS' which energises and remains energised through its 'stick' contact, as long as '19UCR' is released. '19AJS' (intentionally slow to release) now releases because the normally closed contact on '19ALS' opens to remove 'N50' from the '19AJS' coil circuit. A normally open contact on '19ALS' applies the 12 volt supply from the relay room to 19(B)L lever lock, allow the signalman to replace lever 19 normal and free the mechanical locking for another movement.

19AJR:

'462TJR' (462 Track circuit Timing Relay) was energised provided that the 'COLD' contact of timer relay '462TJS' was closed. So '462TJR' released at the start of timing and a normally closed contact was used in the feed to '462TJS' coil which energised when the 'HOT' contact was made. A contact on '462TJS' disconnected the heating element so that, at the end of the cooling cycle, the 'COLD' contact was made, re-energising '462TJR'.

462TJS:

'462TJS' (462 Track circuit Timing Stick relay), in conjunction with '462TJR', enforced a delay before signal 19 could clear if signal 18 was at danger. 'B50' was applied to '462TJS' when an approaching train occupied track circuit 462 and a normally closed contact on '462T1PR' closed, provided track circuit 463 (the track immediately beyond signal 19) was clear. After the heating cycle, the 'HOT' contact closes, applying power to the coil of '462TJS' (via the normally closed contact of '462TJR'). A contact on '462TJS' disconnects power from the heater element but '462TJS' remains energised over its 'stick' contact. At the end of the cooling cycle, the 'COLD' contact closes and '462TJR' re-energises. Now both '19AJS' and '19AJR' are energised, it is possible for '19UCR' to be energised (as described above) and signal 19 may be cleared.

Next:

In the next instalment, we'll tackle something a bit more straightforward, from Sheet 3 of the Contractor's Drawings, 'Incoming & Outgoing TPR Circuits'.

Princes End Electrical Controls (Part 4)

Previous instalments:-
Part 1 Introduction: Drawings.
Part 2 Relay room: cable terminations, relay rack and power supplies.
Part 3 Colour Light Signal 6: Control
Working the box.

Simplified and approximate diagram. Clicking on any diagram displays a higher-resolution version which can be downloaded or printed

Introduction:

We're continuing to study the relay circuits on part of Sheet 1 of the Contractor's Drawings, titled '5(N) Lock & 6 Signal Selection, Control, Lighting & Indication Circuits'.

4-aspect signal head:

Detail of 4-aspect signal head

Each lamp was fed from its own step-down transformer. The primary of each transformer (terminals 1 - 6 on the diagram above) was fed, via control relay contacts in the adjacent location case, with nominal 110 volts a.c.

The signal lamps were dual-filament low voltage bayonet-fitting type. Note that the 'Auxiliary' filament was fed from a lower voltage than the 'Main'. Each 'Main' filament was in series with a lamp proving relay mounted in the signal head ('ER1' to 'ER4'). If current was being drawn by the 'Main' filament, the appropriate lamp proving relay was energised and the 'Auxiliary' filament was disconnected. Release of the lamp proving relay connected the 'Auxiliary' filament via a normally closed ('back') contact.

Further contacts on the lamp proving relays were wired to indicate the status of the 'Main' filaments (terminals 7 - 9 on the diagram above). The contact circuit is drawn rather oddly but the effect is that the signal head presented a closed circuit between terminal 7 and terminal 8 (which was linked to terminal 9 externally) provided any of the relays 'ER1', 'ER2', 'ER3' were energised. The indication contact on 'ER4' (the second Yellow lamp used for the 'HH' 'Double Yellow' Aspect) was shorted out by the external link and thus not used. We'll return to this in '6 EC1PS(M)' below.

The signal head was a rectangular die cast box closed by a hinged door at the rear secured by a padlock. The front of the head had four apertures fitted with projecting sheet steel hoods to minimise the effect of overhead sunlight. Each aperture had a clear cast glass lens (the colour filtering was behind this lens). To project an intense beam visible at a distance, a Fresnel lens was used where the rear of the lens was shaped into a series of stepped rings. Because the Fresnel is so efficient, it could be difficult for a driver stopped close to the signal to confirm the aspect. In early signals of this type, a small second aperture was provided aligned to face a train waiting at the signal. This aperture was also provided with a small hood. Because of the shape of this hood, the device was often called the "pig's ear". However, by the time of the West Midlands Resignalling, a simpler arrangement was in use. The section of cast Fresnel Lens between around 'four o'clock' and 'five o'clock' intentionally had a different profile, which deliberately scattered light towards a waiting train, rather than projecting it forward as part of the main beam.

The signal head was then mounted in a variety of ways, so as to give the driver the best possible 'sighting' of the signal. Straight tubular posts, brackets, massive cantilevers or gantry bridges were used, depending upon the geography. Most of the colour lights on the West Midlands Resignalling were right-hand brackets and, as far as I remember, Princes End signal 6 was of this pattern.

Signal 6 Filament Failure Indication:

Here are the filament failure and indication circuits for signal 6 (468TS coil circuit shown here has already been discussed in Part 3):-

The terminals on the right hand side of this diagram connect to the signal head (see Fig. 7 above). The lighting is derived from a 110 volt a.c. supply in the location case adjacent to the signal (BX110 and NX110). BX110 is fed via the unit '6 R/H/D ECR O/J' and then switched by relay contacts to power the R, H and D lamps. A separate BX110 feed is taken via relay contacts to power the HH lamp. NX110 is connected to terminal 6 (common for the R, H and D lamps) which is linked to terminal 2 (common for the HH lamp).

6 R/H/D ECR:

The '6 R/H/D ECR O/J' unit is detailed below:-

The unit comprises an adjustable resistor (a rheostat) and a bridge rectifier. Alternating current to the R, H and D lamps flows through this resistor, developing an a.c. voltage across the resistor. The bridge rectifier full-wave rectifies this voltage, giving an unsmoothed d.c. voltage which is applied to the coil of relay '6 R/H/D ECR' (6 red/yellow/green lamp proving relay). The black square drawn inside the relay coil indicates the the relay is 'slow to release', preventing relay contact 'chatter' because of the unsmoothed d.c. and drop-outs as the signal changes from one aspect to another.

Provided the adjustable resistor is correctly set, relay '6 R/H/D ECR' will always be energised providing one of the three main filaments or one of the three auxiliary filaments is drawing current. Note that that the HH lamp current is not monitored. If the second yellow lamp fails, it merely means that when the signal should be displaying 'Double Yellow', it will display 'Single Yellow'. Since a 'Single Yellow' is more restrictive, the failure is safe.

6 EC1PS(M):

'6 EC1PS(M)' is concerned with failure of main filaments, hence '(M)'. In 'Detail of 4-aspect signal head' above it was stated that "the signal head presented a closed circuit between terminal 7 and terminal 8 (linked to terminal 9) provided any of the relays 'ER1', 'ER2', 'ER3' were energised. B50 from the location case is fed via these contacts together with N50 from the location case down two wires to the relay room. Here, slow-to-release stick relay '6 EC1PS(M)' is energised through either of two parallel contacts - its own stick contact or a contact on relay 'CANCEL NR'. We'll discuss 'CANCEL NR' in a later part but note the designation 'NR' means 'switch relay'. Failure of a main filament which should be lit will remove the coil voltage from 'CANCEL NR' and '6 EC1PS(M)' will release. Even when the failure has been repaired, '6 EC1PS(M)' will not energise until the signalman has acknowledged, energising 'CANCEL NR'. The stick contact on '6 EC1PS(M)' will then keep the relay energised until the next main filament failure.

6 EC1PR:

'6 EC1PR' (6 lamp proving first repeating relay) in the relay room is concerned with 6 signal 'out'. Provided either a main or standby filament is operating, '6 R/H/D ECR' will be energised at the location case by the signal. B50 and N50 is 'double-cut' at the location case by normally open (front) contacts on '6 R/H/D ECR' and fed down two wires to operate relay '6 EC1PR' provided the signal is lit.

Signal 5 Lever Lock:

Even when the mechanical interlocking allows signal 5 to be cleared, the lever remains locked normal until the electric lock '5(N)L' is energised. This lock is powered from a 12 volt supply in the relay room under the control of '467T2PR', '6G1PR' and '6EC1PR'. In addition, pushing down the catch handle of the lever prior to moving the lever closes an electrical switch '5N'. As the lever is reversed this switch opens to save power. Track circuit 467 is immediately ahead of signal 5 so a 'front' contact on '467T2PR' proves that the track circuit is clear before the lever lock can be energised. Finally, its necessary to prove that there's a lit signal ahead of signal 5. Normally, '6EC1PR' will be energised and a front contact in series with the lever lock proves 6 signal is lit before signal 5 can be cleared. As we discussed in an earlier instalment, trains are allowed to move towards a colour light which is 'out', provided the control relay proves that the signal should be 'off'. Thus, a front contact on '6G1PR' can allow the lever lock to be released even when signal 6 is 'out'.

Next:

In the next instalmen (here) we'll tackle more of the relay circuits, from Sheet 2 of the Contractor's Drawings.

Princes End Electrical Controls (Part 3)

Part 1 of this series introduced the drawings detailing the electrical controls at Princes End after it became a Fringe Box to Wolverhampton Power Signal Box. Part 2 described the relay room with its cable terminations, relay rack and power supplies. There's a brief description of this signal box here. It's helpful to keep in mind the track layout, shown below.

This simplified and approximate diagram shows Princes End with the single line to Wednesbury on the left and the double track to Tipton Curve Junction (controlled by Wolverhampton PSB) on the right. Clicking on any diagram displays a higher-resolution version which can be downloaded or printed

Introduction:

This time, we're going to look at part of Sheet 1 of the Contractor's Drawings, titled '5(N) Lock & 6 Signal Selection, Control, Lighting & Indication Circuits'. A train proceeding in the Down Direction needed the semaphore home signal lever 5 to leave the single line and then colour light lever 6 to proceed into the Wolverhampton Power Box area. Signal 6 was a 4-aspect colour light. Princes End controlled the change from Red to Single Yellow then the aspect of the next signal (WN186) controlled the change from Single Yellow to Double Yellow or Green. The different aspects have code letters as follows:-
R: Red, H: Single Yellow, HH: Double Yellow, D: Green.

Colour Light Signal 6 Control:

Here's the circuitry controlling signal 6:-

Three relays (in Location Case PE2/1 adjacent to signal 6) directly control the signal aspect:-
- '6HR' is controlled from Princes End signal box and relay room. When this relay is released, the signal displays Red, when energised, the signal displays a Yellow (or Double Yellow or Green).
- '6HHR' is controlled from the Location Case in the vicinity of signal WN126. When energised, it produces a Double Yellow (provided '6HR' is also energised).
- '6DR' is controlled from the same Location Case. When energised, it produces a Green, provided '6HR' and '6HHR' are also energised.
We'll now look at the controls on these three relays in more detail.

6HR relay:

'6HR' is fed with 50 volts d.c. from Princes End relay room. Note that both positive and negative feeds to '6HR' coil are switched by contacts on the controlling relays, avoiding a common earth return. This arrangement is called 'Double Cut' and prevents spurious voltages flowing in the earth from incorrectly operating the relay. This is particularly important on electrified railways, where large traction currents are flowing.

'6HR' is energised if all the following requirements are met:-
- '468TS' is energised (meaning the track immediately beyond Signal 6 is clear)
- '469T1PR' is energised (meaning the overlap beyond 'WN186' is clear)
- 'WN186GCZR' is energised (this is the Signal Proving Special Relay for WN186)
- Two contacts on '6(RE)' circuit controller in the signal box are closed.

We'll discuss the operate conditions for the first of these requirements '468TS' (a stick relay) later in this instalment, but we'll deal with the other conditions now.

- '469T1PR' is energised when track 469 is clear. It is a repeater relay for the actual track circuit relay ('469T'). '1P' indicates 'first repeating'.

- 'WN186GCZR' is controlled from a 50 volt supply at signal WN186. Again, the circuit is double cut. Provided'WN186 R/H/D EC1PR' is energised, 'WN186GCZR' will be energised. 'WN186 R/H/D EC1PR' is a Lamp Proving 1st Repeating Relay for signal WN186. Colour Lights are 'proved' by measuring the current flowing through the lamp filament (this was before the days of Light Emitting Diode signal lamps). The 'R/H/D' means we don't care what colour is being shown, as long as it's lit. Should the main filament fail, there's a standby filament (as we'll discuss later). But, it's possible for both the main and standby filaments to fail, meaning the signal is 'out'. We then resort to 'double-blocking' to keep traffic moving. If the controls for signal WN186 are trying to display a 'proceed' indication, it's safe to clear signal 6 to 'Single Yellow' because the track is clear at least to the signal after WN186. So, in parallel with the contacts on 'WN186 R/H/D EC1PR', there are normally open contacts on 'WN186HR' and 'WN186H1PR'. Thus, 'WN186GCZR' in Princes End relay room is energised if either WN186 is lit or WN186 is off.

- Circuit Controller 6(RE) is mounted on the lever frame in Princes End box and controlled by the movement of lever 6. Levers don't just have 'Normal' (N) and 'Reverse' (R) positions. Signal engineers allocate five intermediate positions so the full list is N, A, B, C, D, E, R. So when contacts on a circuit controller are labelled '6(RE)' that means the contacts close just before the lever is fully reversed in the frame and remain closed in the reverse position.

6HHR relay:

'6HHR' is controlled from a 50 volt supply at signal WN186. The feed is double cut and requires 'WN186 R/H/D EC1PR', 'WN186HR' and 'WN186H1PR' at the location case adjacent to signal WN186 energised. In addition, at the location case adjacent to signal 6, '6HR' and '6H1PR' are proved energised.

6DR relay:

At the location case adjacent to signal WN186, the double-cut feed to '6HHR' is fed via contacts on 'WN186HHR' and 'WN186HH1PR' to feed '6DR'. In addition, at the location case adjacent to signal 6, '6HHR' is proved energised.

Colour Light Signal 6 Indication:

The traditional method of indicating the position of semaphore signals to the signalman was by a polarised galvanometer in the signal box fed via a single wire from the signal with earth return. The system was powered by a battery at the signal, fed through a contact box attached to the signal arm. The arm 'On' sent current of one polarity to the box, 'Off' reversed the polarity and anything in between sent no current.

The indication of signal 6 used a similar philosophy, but the circuit used the 50 volt supply at the signal location case and the circuit was 'double-cut' by contacts on '6HR' and '6H1PR'. If the 'Back' (normally closed) contacts on the relays were made, one polarity was sent to line, indicating the signal at Red. If the 'Front' (normally open) contacts were made, the opposite polarity was sent to line, indicating the signal 'Off'.

6G1PR:

'6G1PR' (signal 6 1st Repeating Relay) in the relay room at Princes End was a special relay - basically two relays side by side (called 'N' and 'R') joined by a mechanical latch. The operating coils are wired in parallel and are polarised by a permanent magnet so that the 'N' relay operates for one polarity, the 'R' relay for the opposite polarity. When the 'N' relay operates, it will latch in the operated position (with 'R' released) even with power removed. However, when 'R' operates, it will latch operated and release 'N'. Thus, even without power, the relays will retain the 'last known state'. This type of relay is commonly used for point indication but it is also used for signals to prevent unsafe conditions arising in the case of power or other failure which might inadvertently allow a conflicting or dangerous move to be set-up.

468TS:

The circuit controlling the coil of relay '468TS':-

Track circuit 468 is immediately past signal 6, so it's clear the track circuit needs to be unoccupied before the signal may be cleared. As soon as the train passes signal 6, track circuit 468 becomes occupied and relay 468TS releases, replacing the signal to danger, even though the lever may still be reversed in the frame. The 'stick' relay ensures that, even when the train has gone and track circuit 468 clears, relay 468TS does not 'pick up' until the signalman has replaced lever 6 to 'normal'.

If lever 6 is correctly replaced after a train circuit controller contact '6(NA)' will be closed. As soon as track circuit 468 clears, relay '468TS' will energise via the normally open ('front') contact on '468T2PR' and remain energised through its normally open 'stick' contact even after the signalman reverses lever 6 for a following train. '468TS' will only release when the following train occupies track circuit 468 and the normally open contact on '468T2PR' opens.

Next:

In the next instalment (here) we'll tackle more of the relay circuits on Sheet 1 of the Contractor's Drawings.