Other formats

    TEI XML file   ePub eBook file  

Connect

    mail icontwitter iconBlogspot iconrss icon

The New Zealand Railways Magazine, Volume 1, Issue 10 (March 21, 1927)

[section]

The advent of electric automatic signalling into New Zealand marks the beginning of alternating current as an agent in signalling work in this country. It is true that numerous electric appliances and systems connected with signalling were in use previously, such as Morse and telephone, Winter's block, the tablet system, lock and block, the electric pneumatic interlocking at Dunedin, and numerous electric devices designed to meet necessary requirements as they arose. These, however, were all actuated or controlled by direct current electricity generated by cell power, and were the latest and most efficient for New Zealand conditions as they were successively installed. The expansion of hydroelectric power, giving a comparatively cheap supply of alternating current in practically every district served by trunk lines of railway, has enabled this country to retain its place in the forefront of British enterprise in safety appliances on railways.

Shunt Signal, Otahuhu.

Shunt Signal, Otahuhu.

The British railways, hampered by the possession of more complicated signalling systems, were not in a position to experiment on a large scale with automatic signalling, which reached its successful commercialisation first in the United States. Sporadic installations of automatic signalling were, however, in use in Britain, notably on the London Underground Railway during the process of the greater expansion of these systems.

It was left to New Zealand to pioneer the way in the British Empire with the first installation of single line automatic—that from Lower to Upper Hutt, which has completely justified the enterprise shown. This section, and the double line from Lower Hutt to Lambton, were fitted with arm signals, known as three position upper quadrant, but since these sections were opened further developments have taken place and subsequent installations of automatic have been fitted with daylight colour light signals, which are rapidly becoming standard, the essential methods of controlling the operation of the system, remaining however, practically the same.