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Great Cockcrow Railway
Signalling...

Introduction

The line is fully signalled with 3 signal boxes and 1 gate box to prototypical British signalling based on mid 1950’s practice.

The main terminus of the line is Hardwick Station with 4 platforms with another 2 platform terminus at Cockcrow Hill that also has 2 through lines that avoid the station. Turntables are installed at both termini to turn the locomotives. In the middle of the layout is a through 3-platform junction called Everglades Junction.

There are two Westinghouse style L all electric miniature lever frames in Hardwick Central Signal Box and Everglades Junction Signal Box. Cockcrow Hill Signal Box has a 16-lever "Stevens Knee" frame with mechanical locking. The Railway Signal Co manufactured this frame and it was originally installed at Waterloo Station on the "Waterloo and City" line and is thought to be over 80 years old.

Hardwick

Hardwick is a 23-lever frame that was part of the original Crewe South Junction(which had 227 levers and was in use from 1939 until 1986) and was installed and commissioned in 1993. The Signal Box is equipped as far as possible as an old LMS Signal Box would have looked in around the 1950’s with an illuminated diagram made of timber with a hand painted track layout, and two red lamps at the extremities of each track circuit. In following basic LMS practice, the point operating levers have notched quadrants at the ‘B’ and ‘D’ positions for point indication locking and the signals have quadrant notches at the ‘B’ position for back locking. Of course being an all-electric locking frame ‘A’ and ‘E’ locks and quadrants are provided on all levers. (Euston Station was the one LMS ‘L’ frame not to have indication locking – the points were EP operated and thus it was felt that indication locking was superfluous as the time of point operation was so fast – the detection was added with lever position in the signal lever release circuit).

At Hardwick, following LMS tradition, 1 lever is provided for a signal no matter how many routes are available from that signal. To aid the signalman, above the lever is provided an indication that shows what route (or destination) is presently set for that signal. The pull plates are in front of the lever on a shelf that is standard for all ‘L’ frames (presently with temporary labels, but the intention is to replace them with brass pull plates as originally provided). The signal indications simply show red when the signal is at danger and white when the signal is "off". Although the Railway is completely track circuited, absolute block working is in force to the next Signal Box using Midland Railway type instruments (circa 1914) will full track circuit controls.

Everglades Junction

Everglades Junction is set out as a Southern Railway Signal Box as it would have been around the 1950’s. The Westinghouse ‘L’ frame is of 31 levers and came from South Croydon when the Three Bridges re-signalling scheme was introduced in April 1984. As the frame was installed in 1953 it had quite a short life on BR – even so it is now 50+ years old. The frame came complete and is installed as per the original SR standards in 1980 and expanded and re-wired in 1991. It controls 3 and 4 aspect signalling, and again following SR practice, the aspects on the signals are repeated on the frame including junction indicators. One signal lever controls all possible routes from that signal, with in addition a separate lever for a "warning" route.

Again following SR practice, there are no indication quadrants, the lever position and detection being in the circuit for the release of the signal lever. ‘Free’ indications are also shown above the signal levers.

A standard SR illuminated diagram is provided. Block Working to adjacent Signal Boxes is via Southern Railway Standard instruments (circa 1920’s) with full track circuit controls.

In true SR practice, the "tapper" for the Block Bells is not part of the bell but mounted separately using brass plungers.

There is also a Train Describer using a VDU display with automatic code ‘set up’ and automatic ‘code change’ to help the signal men keep track of the trains, and to also keep a count of the number of trains run over the system in any one day.

Cockcrow Hill

Cockcrow Hill Signal Box is a 16 lever Stevens "Knee Frame" with mechanical locking and was commissioned in May 2001 replacing a LMS 1943 tappet frame after the layout at Cockcrow Hill Station was completely re-modelled. The new layout allows a loco to run round a train without conflicting with the Main Line. 12 levers are fitted with combined lever locks and circuit controllers and the other 4 levers have circuit controllers only.

Relay Rooms

All Signal Boxes have Relay Rooms containing the necessary relay racks, power supplies and cable termination racks.

Hardwick relay Room is contained in a Portable Office building that also acts as the S&T office! Everglades Junction Relay Room is a concrete block building that used to be the original Signal Box in the early days of the railway before power signalling was introduced. Cockcrow Hill Relay Room is a purpose built brick building with a pitched roof to blend in with the Signal Box.

The Future

Future plans for the signalling of the Railway include bringing into use a "LNWR – all-electric" frame that was originally installed at Manchester – Mayfield Station – thought to have originated from around the 1900's but we are open to corrections! (That should cause some head scratching amongst the readers.) This would be at Lesters Crossing.

Running around 60/70 trains over a layout that is up to 2 miles in length every Sunday does mean that the Railway needs a minimum of at least 20 people on duty. The signal boxes are also very busy - In fact it is claimed that they are the busiest working signal boxes in the UK (well certainly on a Sunday!). The railway operates to a modified BR1961 Rule Book. (As you would expect, references to trolleys, platelayers, detonators, fog and falling snow etc. have been removed!). BR Block Signalling Regulations are used from the same era and all operating staff are tested regularly for their knowledge of the rule book and signalling regulations. There are no legal requirements laid down by the HMRI (they only come into force on 15 inch gauge and upwards) but there is a set of recommendations written by the HMRI based on the GCR and other miniature railways.

Details of Equipment Used

Location Cupboards

Full size locations are situated as required around the Railway and contain Track feeds and relays. All Signal Controls are housed in the Relay Rooms and direct feed all of the signals via multicore cables of the required size. Cockcrow Hill is slightly different as most of the track circuits are fed direct from the Relay Room. All Locations are fed with 110 volts 50 Hz and have heaters and lighting within the location. All locations are wired to BR Standards (circa 1992) and standard BR type cables connect the location to the trackside equipment via 2BA sliding links.

Track Circuits

The Railway is laid with Aluminium rail and both oak and plastic sleepers, 71/4 inch gauge. Track circuits are fed via a Transformer/Rectifier (ex Reed Amplifier Power Supply Units) with an adjustable 20-ohm resistor and use a 12v BR 930 Spec. relay with a minimum pick-up of 6.3 – 7.1v. (Reed followers are very useful!) The rail is bonded at the joints and we make our own insulated joints.

Point Machines

Point machines are made up from 12v Ford Escort Wiper Motors (extremely reliable!) with microswitch detection circuits on machine operated and some spring-operated points. The insulated front stretcher is made from polycarbonate strip and the point machines have an integral FPL.

Signals

Colour light signals are made up from SGE/WBS/Tyers block shelf indicators stacked as necessary, fitted with polycarbonate coloured lenses and aluminium display boards. The bulbs are 12v. 2.4w. Junction Indicators are 12v individual lamps mounted as required. Semaphore signals (both upper and lower quadrant) are solenoid worked with a constantly rated 24v. 12w. Coil, sealed for out-door use. Semaphore signals can be electrically lit using 12v. 1.2w. Lamps switched on from the controlling signal box. All Signals are plug coupled and are removed at the end of the running times.

Power Supply

Power is distributed from Everglades Junction and Hardwick at 110v. 50 Hz. via duplicated 240/110 transformers located at Everglades Junction. Cockcrow Hill area is also fed from 240/110 transformers located at Cockcrow Hill. There is a means of feeding Cockcrow Hill from Everglades in an emergency.

Communications

There are Signal Post Telephones at all controlled signals with an electronic PABX for other telephones. We also have hand held radios for all operational staff.

Cable Routes

Most cables are buried but there is a small amount of concrete troughing installed.

Reliability

The signalling system is extremely reliable and failures are extremely rare. (Approx. 2/3 incidents a season) All relays are BRB 930/960 specification and live in heated Relay Rooms and locations. Considering that the power is turned off from Sunday evening to the following Sunday morning in the summer, and is off during the Winter months from November until the end of April – when switched on, it always works.

We get the very occasional point problems (stones in blades!) and sometimes a broken track circuit bond caused by someone walking on the track and accidentally kicking the bond! (A problem with miniature railways!)

Design and Construction

All design and construction is done in-house by the S&T department with the relay room and signal box circuits being hand drawn in pencil on A3 size paper. The location diagrams are drawn using a computer and AutoCAD on A4 size drawings.

The S & T department, as you would expect, is mainly made up of Institution of Railway Signal Engineers' members and totals 8 people, (two of whom are ex-Presidents!) and gives the opportunity to all to continue to increase their professional development!

The Railway is, in fact, a wonderful training aid for all S & T Engineers (as well as operating colleagues) and has been used by other organisations such as the HMRI!

A complete schematic is available from this link

The GCR welcomes any person (or indeed Organisation) to view the signalling in more detail – you could of course, for a suitable fee, even use it for training - PTS Certificates are not needed!

Hardwick Central