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29th November 2008 The A1 Electrical Story With the successful completion of the A1’s three main line test runs, it is time to say some more about the A1 electrical system, which we are pleased to report is meeting all our expectations as a system fit for intensive use on the national rail network.
In this first update, we talk about the A1’s lighting system, which is the first of its kind to be installed on a British steam locomotive.
Part 1 - The A1 Lighting System External Lighting Those who witnessed (or have viewed the videos of) the high speed run on 18th November will have seen, for the first time in the UK, a steam locomotive featuring a headlamp which complies with the luminous intensity requirements of the latest Railway Group Standard for visibility of trains (GM/RT 2483), applying to trains travelling in excess of 60mph.
The A1’s head, tail and marker lamps have been designed from scratch using high power LEDs. These give a high light output and are very efficient in their use of power. Our LED headlamp consumes less than 25 watts. A conventional lamp with the same output would consume around 150 watts. They also have a very long operating lifetime – typically in excess of 40,000 hours (compared to around 1,000 hours for a conventional bulb). Alan Green, an experienced optical physicist at Sagentia in
To meet the Group Standard, the A1 actually needs two different headlamps. On the fireman’s side is the day time headlamp. This has full brightness for daytime running and is designed to be visible to staff and other trains at the maximum possible distance. The one on the driver’s side (which the engine carried on 18th November) is the night time headlamp. This has a reduced brightness and a different shape of beam for running at night. This is designed to avoid disturbing the night vision of oncoming drivers or those working on stations and on the track. We also have a “hazard warning” mode, where the driver can switch both lamps to flash as a warning to other trains in case of emergency. The high speed run on 18th November was the first time in the Crew Lighting – Tornado component on Tornado Our “clean sheet” design has also allowed us to build into the A1 a number of features to help the locomotive crew and those working on or under the engine. Working closely with David Elliott, Director of Engineering, and Graeme Bunker, Director of Operations, we have included lighting in the cab and around the loco to meet these needs. Firstly, we have installed a number of bulkhead lights between the frames to assist with inspection, maintenance and oiling. Secondly, we have provided six plug-in points for 24v handlamps around the loco and tender. It is sometimes difficult at night for the fireman to see if the injectors have picked up cleanly and we’ve therefore installed bulkhead lights under the bottom crew step on each side of the loco to illuminate the injector overflows. These have taken on the name “landing lights” and are also useful when crew members need to alight at night as they illuminate the ground immediately below the bottom crew step. You will have seen these lights in use between Additional lighting along the outside of the frames is planned and will be installed when time permits. We are also in the process of fitting LED lamps in all the fittings to improve system reliability still further. Inside the cab we have worked closely with Graeme to provide an optimum lighting system to help the crew work the engine at night. As on the original A1s we have two roof-mounted bulkhead fittings to provide cab space lighting. For the instruments we have decided to avoid any wiring on the backhead and instead provide all the instrument and gauge lighting from small light boxes fitted to the cab roof. We currently have two of these, one for the driver’s instruments and another for the fireman’s. We’re in the process of fitting additional light boxes to illuminate the coal space and the tender instruments. The driver’s box contains ten individually steerable LEDs and the fireman’s box has five. These have been directed to illuminate all instruments, reverser indicator and water gauges. We have provided dimmer controls on each box so the crew can adjust the light output to suit the lighting conditions and their own preference. Quite by chance, the potentiometers we selected for the instrument illumination controls are made by Meggitt Citec and are of the exact same type used on the Tornado aircraft project. So, there is a common component used on the aircraft and the locomotive bearing the same name – a nice touch we think. Conclusion Together, these systems provide the lighting needed for the safe operation of the A1 during the day and at night. We’ve built in lots of flexibility for the future and you can expect to see further additions and enhancements to the system as we gain operating experience and gather feedback from everyone who works with the engine. Acknowledgements In addition to all the hard work put in by the A1 electrical team we are also most grateful for the assistance and advice we received during the last 18 months of design and build from our friends in the industry. I would like especially to thank Bob Meanley, Ian Howitt, Jim Burrows and Ken Grubb for their invaluable help in specifying the system and selecting tools and materials. Mandy Sharpe, of Sharpe Engineering Solutions, designed and installed the AWS/TRPS and OTMR systems for us and we’re very grateful to Mandy for all her assistance too. We also had extremely useful inputs from Martin Bratt of EWS and Jon Hemsley of Delta Rail. And we mustn’t forget John Beesley for sponsoring and constructing the headlamp housings. Together these people helped us get this all-new design pretty well right first time, so its success is not just down to the A1 team, but also to these other talented engineers from across the railway business. They generously gave us the benefit of their practical experience of what does and doesn’t work when you bring modern electronics together with steam. Thanks to you all! To follow If you’ve found this update interesting then look out for Part 2 in the story, which will explain how we generate and control the electrical power on the A1. 23rd November 2008
21st July 2008 Progress on the electrics has continued apace. Paul Depledge has now completed all the main electrical system conduit work on loco and tender. He has also installed all the conduit for the TPWS (Train Protection and Warning System) and OTMR (On Train Monitoring and Recording) and pulled through all the plain cable in preparation for A six day visit from 16th June 2008 Paul Depledge has been making good progress on the system installation in Darlington. All the major wiring looms are now pulled through and he has been concentrating on installing the conduit for the TPWS and OTMR systems, and on the remainder of the cab conduit and wiring runs.
Alan Green has now completed manufacture of the first in the production batch of six marker and six marker/tail optics units. This will give us four of each for the loco/tender and two of each as spares.
27th May 2008 Paul Depledge has now completed the main conduit runs down the loco and tender and with the assistance of Mick Robinson has started loom making and pulling cables through the conduits. Paul has completed virtually all the boxes and other mechanical components of the electrical installation on loco and tender. Volunteer Rob Payne has assembled the essential and auxiliary I/O (Input/Output) boxes. The Essential Services box is in the process of being fitted out and the Auxiliary Services cabinet (which is smaller and less complex) will be completed by our electrical designer, Rob Morland in his own workshop. Additional work has been required to re-fit the alternator and its regulator following the reinforcement of the tender back drag box. The front and back marker lamp boxes and associated conduit work have been fitted. The electrical system design is now essentially complete. The only areas where more work is required are the marker and head lamps (where the LED system has to be finished and the units constructed). Thanks to our recent appeal the Trust now has all eight required plus spares. The internal layout of the battery boxes is now complete and CAD drawings are being produced by David Elliott. Each box will contain two batteries and a Battery Panel, to which will be fitted the DC-DC converter battery charger and associated protection components. The first power supply has been wired up to test the DC-DC converter charging a set of batteries. Using the shore supply this has been bench-tested through two complete battery charge-discharge cycles and performed without any problems. The first item of circuitry to be carried on the loco has now been built and tested. This is the simple circuit that provides a health indication via LEDs on the Control Panels for each of the input and output supplies. Boards containing four of these circuits have been assembled and potted in flame-retardant silicone elastomer. Two units are required and four boards have been built, providing two spares. On the loco itself, the key challenge has been to identify the best routing for the wiring between the cab, frames and battery boxes. This is a very congested area and it was important that we came up with an arrangement that is reliable and maintainable. Paul Depledge has managed to fit in enough conduit capacity which has allowed the circuit schematics and wiring lists to be finalised. Rob Morland is in the process of assembling and testing the Input/Output and Battery Box panels and will deliver them to Darlington as complete units ready for fitting.22nd April 2008
24th March 2008 Paul Depledge continues to make progress with the conduit runs and boxes for the electrical system The Trust hosted a visit on 26th January by Martin Bratt, head of electrical engineering at EWS. Martin spent much of the day with us in Darlington and provided extremely useful, practical information on a range of issues concerning the electrical system design and installation. Having incorporated a number of minor changes suggested by Martin, the electrical system design is now essentially complete. The only areas where more work is required are the marker and head lamps (where the LED system has to be finished and the units constructed). Thanks to our recent appeal the Trust now has all eight required plus spares. The parts list now contains all the items known to be required for the build. A number of consumable items (connectors, conduit components, boxes, etc) will be added as these are procured for the installation. Rob Morland and David Elliott have completed the design of the two under-seat panels. David has committed the designs to CAD. These panels contain the majority of the circuitry for the Essential and Auxiliary Services Supplies. They are now out for fabrication. The internal layout of the battery boxes is now complete and CAD drawings are being produced by David. Each box will contain two batteries and a Battery Panel, to which will be fitted the DC-DC converter and associated protection components. The first power supply has been wired up to test the DC-DC converter charging a set of batteries. Using the shore supply this has been bench-tested through two complete battery charge-discharge cycles and performed without any problems. The first item of circuitry to be carried on the loco has now been built and tested. This is the simple circuit that provides a health indication via LEDs on the Control Panels for each of the input and output supplies. Boards containing four of these circuits have been assembled and potted in flame-retardant silicone elastomer. Two units are required and four boards have been built, providing two spares. On the loco itself, the key remaining challenge is to identify the best routing for the wiring between the cab, frames and battery boxes. This is a very congested area and it is important that we come up with an arrangement that is reliable and maintainable. This will allow the circuit schematics and wiring lists to be finalised. Once the conduit runs on loco and tender are complete, Paul Depledge will start pulling the wiring looms through. In parallel with this Rob Morland will assemble and test the I/O and Battery Box panels, which will then be delivered to Darlington as complete units ready for fitting. We can then terminate all the wires, assemble the connectors, bus-out and check all the wiring, connect the panels and commence final system test. 19th January 2008 Paul Depledge has been making good progress with the electrical installation on the tender and is now beginning to prepare for the TPWS installation by accumulating the various junction boxes required to terminate the antenna connections. The bulk of the LS0H wire has been delivered to Darlington. This will allow the pulling-through of the main wiring into the conduit runs as these are completed on locomotive and tender. David Elliott and Rob Morland have been working through the design of the in-cab system, which has taken some time as there is very restricted space available under the two crew seats for all the electrical equipment that is required. After looking at a variety of standard enclosures we have finally concluded that the best solution will be to construct our own to fit precisely in the spaces. These will be fabricated from 3mm steel plate and we will have them laser cut with all the holes needed for switches, connectors etc. Rob Morland will build and test the complete I/O Panels before delivering them to Darlington for fitting. David Elliott has completed the AutoCAD drawing for the Essential Services I/O Panel (under the driver’s seat) and Rob is currently preparing a sketch of the cut-outs required in the front and rear panels. Once completed David will put these onto AutoCAD and they can then be loaded directly into the laser cutter to complete the panels. The metalwork will be painted for protection. David is currently working on the drawing for the Auxiliary Services I/O Panel (under the fireman’s seat). For the Control Panels (which are located on the inside cab roof) we have been able to use standard diecast aluminium boxes, which are at Darlington for fitting. In this case the electrical installation will be attached to the front panel of each box – once again Rob will complete this work at home and the panels will be delivered to Darlington for fitting. One pair of the 65AH batteries is now in Darlington to assist in the design of the interiors of the battery boxes. As with the under-seat cubicles, space is at a premium here, so getting the shelves in the right place is going to be important if everything is to fit and remain accessible.
The first of the DC-DC converters has been delivered to C. P. Power in the UK and we will receive this shortly. This will enable work to proceed on the next stage of electrical circuit design, build and test. Most of the MIL-C-5015 connectors and all the specialist tooling have now been delivered to Rob and are awaiting completion of the under-seat cabinets to allow the wiring to commence. Roger Burgess has completed an excellent initial AutoCAD drawing of the main circuit schematic. This looks very good and we now await completion of the remainder of the design, at which point we will be able to provide Roger with a full information pack to allow completion of the drawings. Rob Morland has modified the Stones cast bronze marker lamps to incorporate red and white LEDs. However, the Trust needs two more (of eight in total) for Tornado. In addition to the A1s, they were fitted to some early diesel shunter classes including 03 and 04 plus various 0-4-0 designs by North British, Hunslet and Barclay. 20th December 2007 The overhauled coach alternator is back with Ian Howitt for fitting to the tender frame, along with the regulator box. Paul Depledge has recently started work at DLW to fit conduit and terminal boxes round the engine for the electrical system. Rob Morland has continued to detail the electrical system with cable being ordered and delivered. David Elliott has spent much time on the layout of the under-seat cubicles to fit in TPWS equipment and main busbar/distribution panels.7th December 2007 27th November 2007
22nd October 2007
16th September 2007 Following completion of the detailed circuit design for the locomotive and tender electricals, components have now been selected and a parts list created. This contains over 330 items (excluding individual auxiliary lighting components, most cables and connectors). David Elliott has completed the outline mechanical and space design for the under-seat electrical panels within the cab. There is just enough room to mount the TPWS and OTMR units, along with our input/output panels, under the driver’s and fireman’s seats. The main charging, protection and power distribution systems for the two supplies (essential and auxiliary) are new designs and therefore need to be built-up and tested before installation on the locomotive. Rob Morland will build one of each of the new circuits and test these for basic functionality before shipping to Darlington. 13th August 2007 The OTMR (the monitoring and recording unit) has now been delivered to Darlington and will soon take its place in the mounting position under the cab. On the wider electrical "front" the full specifications are nearing completion.
21st May 2007
The Stones cast bronze lamp fittings are a conspicuous feature of the A1 locomotives so it was felt that they should be provided on 60163 TORNADO. In 2000 the A1 Trust was offered 3 lamps by a collector who was disposing of some of his collection, and these were acquired, and featured on the photograph which formed the front cover of Steam Railway in July 2005, with the centre bufferbeam lamp conspicuous by its absence. At the end of March this year, a Stones lamp appeared on e-Bay and by mid April had been acquired for the A1 Trust by Peter Neesam, who, when not making and fitting cladding for the boiler at Darlington Locomotive Works, spends an unhealthy amount of time on e-Bay looking for railwayana! This lamp had been converted for mains operation, but still retains its mechanism for changing from white to red, to form a tail lamp. When originally fitted to the the A1 class, each lamp was switched on or off by a switch located on the underside of the lamp body. The handle on the side of the lamp rotates through 180 degrees to move a red filter in front of the bulb
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The system has been designed, built and installed by the A1 electrical team of Rob Morland, Alan Green, John Beesley and Paul Depledge. It is one part of the new A1 that is very different from the original Peppercorn design.
Steam locomotives currently have a derogation to use a portable headlamp up to 75mph, but as we were able to start from scratch on our design, we’ve decided to go for the full standard, which requires a much brighter light than can be practically supplied from a portable battery-powered lamp. This might sound like a simple change, but it has significant implications for the system design. Firstly, the head and tail lamps are Essential Systems, linked to the safety of the railway. We therefore need to satisfy our Vehicle Acceptance Body (VAB) that they meet the specifications laid down and are as reliable as reasonably practical. So, we needed duplicated power supplies, two battery systems, two means of generating power whilst on the move and sufficient battery storage to complete a duty even in the unlikely event of both generators failing. We also needed sensors for each lamp wired to indicators in the cab so the crew can confirm that all the lamps selected are working. We decided to go for a “belt and braces” design that provides all this, and more.
The marker and tail lamps use the original Stones marker lamp housings and lenses donated by Covenantors, but feature a new optical system with electrical switching between white and red LEDs for head and tail displays. The headlamp consists of a cluster of seven high-power LEDs built into a new assembly and enclosed in a lamp housing designed and built specially for us under a generous sponsorship by 
Rob Morland has been fitting components into the I/O (Input/Output Panels and initial termination of connectors. David Elliott is engaging Mandy Sharpe to carry out a turnkey job to install, commission and test the TPWS and OTMR system, planned to take place in July.
Additional work has been required to re-fit the alternator and its regulator following the reinforcement of the tender back drag box. Otherwise Paul Depledge continues to make good progress with the conduit runs and boxes for the electrical system. Volunteer Rob Payne has assembled the essential and auxiliary I/O boxes which along with the GN Steam-made under-cab routing boxes are presently being zinc plated and passivated. The front marker lamps have been fitted and Paul is presently fitting and conduiting the rear marker lamps.
The overhauled coach alternator is back with Ian Howitt for fitting to the tender frame, along with the regulator box. Paul Depledge from ID Howitt has visited to discuss installation of the electrical conduit and wiring work. As a consequence (and with VAB approval), the decision has been made to use flexible conduit wherever possible to save complex bends in solid conduit and difficulties with subsequent pulling through of cables. Rob Morland is working on the modification to the marker lamps to incorporate red and white LEDs, and has ordered a substantial quantity of electrical components. The VAB has indicated their acceptance of the EMC (Electro Magnetic Compatibility) of the solid state battery chargers which is a significant step forward.
Rob Morland has made further progress with the electrical system and is developing (with a colleague) modifications to the marker lights to use LED bulbs and to incorporate red and white LEDs in the same lamp housing. Leyland Auto Ltd at Bamber Bridge has been instructed to overhaul one of the coach alternators to fit under the tender. Work has started to locate the steam turbo alternator behind the RH smoke defector to enable completion of the steam pipe work. Work is in hand to finalise the conduit routes from front to back of the frames. Rob is also in further correspondence with the VAB on acceptance of our electrical specification.
Great progress is now being made with the electrical side of the locomotive.
The Peppercorn A1 Pacific was one of several LNER classes built with electric lighting powered by a Stones 350W turbo-generator. This system provided marker lights on the locomotive and the tender, illumination for the cab and gauges, and sockets on the frames to plug in inspection lamps. 4 lights were provided on each end of the locomotive in the conventional lamp bracket positions so that the standard head codes could be displayed. In practice it would appear that the generators were not very reliable as almost all pictures of electric light fitted locomotives show them carrying traditional oil lamps as well. This is hardly surprising,as until the advent of Automatic Warning System (AWS) in the late 50s, most steam sheds had little or no dealings with electrical equipment and no (or only primitive) facilities for maintaining it. Indeed when AWS was adopted on a widespread basis, separate batteries were provided, these being charged regularly on depot.
The steam driven turbo-alternator which will be one of the sources of power generation on the locomotive has now arrived.
Also recently delivered has been the drive pulley which will be fitted onto one of the tender axles and which will drive the tender mounted alternator - this will be the major source of electrical power with the steam driven alternator being run when the locomotive is stationary for extended periods.