Other formats

    TEI XML file   ePub eBook file  


    mail icontwitter iconBlogspot iconrss icon

The New Zealand Railways Magazine, Volume 3, Issue 4 (August 1, 1928)

Automatic Signalling and Train Control

page 36

Automatic Signalling and Train Control

“Keep the wheels moving”

Within the last nine months several links have been forged in the chain of electrically interlocked stations with three-position colour light signals, on the New Zealand Railway system. The outstanding benefits of the new installations are the better signalling facilities and the greater flexibility and safety of train movements which they give.

The Addington North box was the first to be equipped with the new system, being converted from mechanical to electrical operation on 5th November, 1927. This installation (worked under complete automatic block) was the means of completing the system between Addington North and Middleton shunting and marshalling yards, thus enabling goods road access between the two yards by an independent road for “Up” and “Down” goods traffic. There are various sidings connected with this road, and these are locked and worked by single line switch locks and ground levers.

Illustrating the Old and the New System of Signalling at Addington, Christchurch.

Illustrating the Old and the New System of Signalling at Addington, Christchurch.

The switch locks control the entry of a train on to the road from either end, and must be normal with points locked before the entering departure signals are operative. The mechanical frame at Addington was retained, and adapted to work with the new system.

Papatoetoe was the next station to be opened, and came into operation a month later, on the 5th December, 1927. This station, in conjunction with the new double line which was extended from Otahuhu, has been of immense benefit in the handling of traffic, the single line having previously had a throttling effect on train movements.

Incidental with the opening of this station, the first section, operating as far as Drury, of single line automatic signalling with three-aspect colour lights, was brought in. The second section (Drury to Mercer) followed a week later.

These are the first sections of single line automatic signalling to be brought into use in the Auckland district. They are being worked under the supervision of a train control officer. A selector telephone worked in conjunction with the automatic signals enables the train control officer to have a complete knowledge of all train movement. The control officer is within call at all times. All train movement is graphed on a train diagram as advice is received from stations, and the graph becomes a visual picture of the moving train service. The constant supervision of the controller enables him to anticipate crossings, and have crossing orders in readiness for issue to train men.

The knowledge of how the work of trains is being carried out at stations is a very important factor, because it results in the speeding up of goods trains, which means considerable economy. By this system the work of goods trains can be arranged systematically to fit in with other traffic movements, and as a result, delays are cut out. Pending the installation of the three-position automatic signalling (which is being pushed forward at the present time) train control is also being worked, under tablet, as far as Frankton.

The train control system has also been installed between Wellington and Marton in the North page 37 Island, and between Christchurch and Oamaru in the South Island. These two latter sections, as in the case of the former, are worked under the tablet system.

To the Wellington-Marton section, the Lambton-Upper Hutt signalling train control has been added, and to the Christchurch-Oamaru section that of the Christchurch-Arthur's Pass, or Midland section of signalling. This latter section has been fitted with telephone call lights (which are known as “T” lights) by means of which the train control officer may intercept a train at an unattended crossing loop for special instructions re crossing, etc.

Home Signals for Auckland and Tauranga Lines, Paeroa Junction.

Home Signals for Auckland and Tauranga Lines, Paeroa Junction.

The indications are displayed by a powerful white light having a block letter “T” painted on the inside of the lens. The light can easily be picked up in daylight for a distance of two or three hundred yards. These indications are exhibited both ways and as soon as any particular loop has been selected the lights remain on until the call has been answered, the opening of the telephone door box restoring the arrangement to “Normal.” (Two photos accompanying this article show the light before and after a call has been made at Moana, which is on the Otira-Stillwater section of the Midland line.)

Train Control Telephone Call Light at Moana (Midland Line) showing Light on.

Train Control Telephone Call Light at Moana (Midland Line) showing Light on.

Paeroa Junction has also to be added to the list of electrically interlocked stations, this station having been opened on the 10th June last. On the day of opening, and since, it has given every satisfaction. This installation comprises a full electric interlocking and is worked (as with other “full electric”) from the station office. The levers total 34, the frame being built by McKenzie and Holland Proprietary Ltd., Melbourne.

Yard shunting movements are controlled by two ground frames, one north and one south, so that shunting can be carried on independently of station control, once permission has been given by lever.

Paeroa is an important junction (and will become increasingly so in the future) because all the new East Coast, Tauranga and Taneatua traffic has to be handled there. As many as four trains at a time have to be re-marshalled, one of the trains (ex Tauranga) having to be turned to complete its journey to Auckland.

Whilst on the subject of electric interlocking there is one more small installation that must not be forgotten. This is at Kensington on the south side of the Dunedin goods yard, and now controls the “inward” and “outward” goods traffic from the main yard to and from the south. This is only a small contribution to the electric control of
Train Control Telephone Call Light, Moana, showing Light Off.

Train Control Telephone Call Light, Moana, showing Light Off.

page 38 points at the latter place, but the part it plays is very important. Previous to this installation the whole “inward” and “outward” goods traffic was handled through the main passenger yard. This meant that all inward trains had to run past the yard on to the main station road, and be handled from there back to the goods yard, a procedure which entailed much extra work and caused delay. This also applied to outward trains in a reverse way. The application of electrically worked points made it possible for the points now controlling the “inward” and “outward” movements to be worked a distance from the Kensington signal cabin, the latter movements not being practicable by mechanical means.

With reference to the extension of three-position colour light automatic signalling overseas there is great enterprise and interest shown by the railway authorities in Great Britain where the system is being speedily adopted for the handling of dense traffic.

The Southern Railway has decided to embark on an expenditure of £150,000 for the installation of colour light signals to replace the existing semaphore signals. This is following on a system, which was installed last year on the Holborn Viaduct to Elephant and Castle and Charing Cross, Cannon Street and Borough Market Junction sections of the line. This latter proved so successful that the railway officials decided that it was the most efficient method, especially in foggy weather, of dealing with the intensive services which are handled on the inner London area.

(Photo, W. W. Stewart.) Loading Luggage at Auckland Station.

(Photo, W. W. Stewart.)
Loading Luggage at Auckland Station.

When this is completed the Southern railway will have the most extensive installation of multiple colour light signalling in Europe.

It is an interesting fact that the installation of automatic signalling with alternating current is being energetically pushed forward in all parts of the world and it is worthy of note that in this respect New Zealand led the way throughout the British Empire, being the first country to instal automatic three-position signalling operated by alternating current.

Automatic Signalling and Train Control keep the Wheels Moving.

Myers Cricket Cup

The annual match between the staffs of New-market and Petone Workshops for the Myers Cricket Cup was played at Auckland a few weeks ago, and aroused considerable local interest among railwaymen. The opposing teams were in good form and gave the spectators an exhibition of first-class cricket. The contest resulted in a win for Newmarket by one innings and 38 runs. The cup is therefore held by Newmarket for another year. The nonparticipation of the other workshops (East Town, Addington and Hillside) in these annual contests is much to be regretted, and it is hoped that they will fall in line for the competition next year.