This page explains the principles of New Zealand signalling and safeworking. The emphasis is on automatic signalling and the Hutt Valley Line.
(Right) The Johnsonville Branch Up Departure signal. The All Trains Stop board was installed after a wrong side failure with a tri-colour signal head in Australia (Jan 2008). Special procedures applied to passing this signal until the tri-colour unit had been replaced with a three light LED unit. The smudge is on the EMU front window, not the camera lens!
The safe operation of a railway depends on the signalling (i.e. the hardware) and the operating rules that define how the hardware is to be used (i.e. the software). My Signalling Overview page decribes the combinations of hardware and rules used in New Zealand.
Signal aspects are explained in New Zealand Signal Aspects and also the NZR training document Illustrated Guide To Three Position Colour Light signals. This booklet dates from the 1960s or 1970s and does not describe two newer aspects - Advance Caution and Intermediate Speed.
The signal classification determines the rules that apply when a signal is to be passed at stop.
A set of six photographs demonstrate overlaps on the Hutt Valley Line.
The railway in New Zealand has used various signal configurations for controlling the exit of a train from a loop - ground lights, single unit running signals and double unit running signals. My Loop Exit page uses diagrams and photographs to document examples between Ngauranga and Featherston.
I explain permissive working.
Ngauranga To Wellington
The Ngauranga to Wellington section provides a variety of examples of New Zealand double line automatic signalling practice, including:
Wellington Junction Signalling
New Zealand railways use speed signalling. However there are locations where the signalling indicates the route and speed boards define the authorised speed. One example is Up trains at Wellington Junction. In contrast Down trains at Wellington Junction are directed with signals that more closely follow speed signalling conventions. On both of these pages I use a diagram and some photographs to show how notice boards can change the meaning of a signalling installation.
Wellington Station Layout
Mechanical Points Indicators
A diagram and photographs explain the rules applying to mechanical points indicators.
Trap Point Operating Mechanisms
Trap points and safety points protect the mainline and loops from runaway vehicles. I have created a series of pages which use diagrams and photographs to explain the mechanisms used to operate these points.
My Safe Working page provides links to html and pdf versions of the following safe working documents:
19th Century Signalling
In 2004 at Masterton some interesting relics of late 19th/early 20th century signalling are still in regular use on the commercial railway. Masterton is the only location I know of where a Woods key is still used and is one of only two or three stations that have two-position signals.
Hutt Valley Signalling History
My Hutt Valley Signalling History page documents the history of signalling in the Hutt Valley and also on the Rimutaka tunnel route to Featherston.
South Junction Temporary Signalling
In March 2002 a low-speed light was installed on the Up Departure signal at Pukerua Bay. The purpose was to allow Up EMUs to reverse on the single line during a Block Of Line. The line was closed between South Junction and Waikanae for tunnel floor lowering and other work.
The Wellington - Johnsonville Line is now controlled by CTC but has had some interesting features over the years. Although it is not in the Hutt Valley I have created a Johnsonville Line Signalling page. Some of the interesting features include:
A variety of boards are seen by drivers as they go about their daily work.
Colour Light Shunt Signals
Although the same set of rules applies to every shunt signal, the way in which individual shunt signals operate can differ. I explain the rules applying to shunt signals and then, using Petone as an example, explain some of the ways in which their operation can differ.
My Comparative Aspects page compares the aspects used in New Zealand with those used by the Rail Infrastructure Corporation (RIC) in NSW and the Burlington Northern and Santa Fe (BNSF). The comparison is not a comprehensive explanation of RIC or BNSF signalling. The purpose of the page is to demonstrate that there are many different ways of defining colour light signal aspects.
Last Updated: Tue 28 May 2013