Upper Hutt CTC Panel

The Upper Hutt CTC panel, which was installed in 1955, controlled the Trentham - Upper Hutt - Featherston single line section. This page describes the panel as it was in May 2006.

Over the weekend of 16/17 December 2006 control of Featherston was transferred to Train Control. Trentham followed on 6th February 2007 and Upper Hutt on February 25th.

Some of the information on this page is my interpretation of the information available to me, so should be treated with caution. Note also that the panel is very difficult to photograph with a hand-held point and shoot camera.

Upper Hutt Panel

Control Machine number 12 was in use for over 50 years.


The Green Machine

The Upper Hutt panel is two machines in one - a conventional panel for Trentham - Upper Hutt and a time code machine with electro-mechanical storage for field stations in the Upper Hutt - Featherston section.

Direct Control The left-hand side, which controls Trentham to Upper Hutt, is probably near original. Cross-overs at each end of Upper Hutt have been removed, the south backshunt truncated and the yard has gone, but the diagram still has the older style indication lamps.

The points and signals are directly controlled - i.e. it is not necessary to press a Start button. Operation is similar to the other Hutt Valley signal boxes - Taita, Woburn and Petone.

Remote Coding The right-hand side, controlling the single line section through the 8.8km Rimutaka tunnel to Featherston, was probably replaced sometime between 1994, when the Rimutaka loop was removed and Maymorn converted to a single-ended siding, and 1999 when the Maymorn siding was removed. The tunnel timer (right) and the tunnel indications (fourth panel from right) were not in the original installation. Smaller, non-original indication lamps are used on this section.

Featherston control codes are sent, and indications received, by time coding i.e. A Start button must be pressed to send a command. The Upper Hutt Up Departure signal is also cleared by pressing a Start button, although there is a switch for use when CTC has failed.

In 1955 the five narrow panels on the right (only four shown) were for Upper Hutt, Mangaroa (Maymorn), Centre of tunnel forced ventilation (not installed), Rimutaka Loop and Featherston.

Click on an image for More Information.....

Bell Codes

Bell Codes. Until well into the 1990s bell communication was used between Upper Hutt, Taita, Woburn, Petone and A-Box, Wellngton.


Trains In The Tunnel. Several features have been added to the panel to enhance the safety of trains in the Rimutaka tunnel.

Half Blocks

Permissive Working is permitted in the single line Trentham - Upper Hutt and Upper Hutt - Featherston sections.

Indication Lamps

Indication Lamps Older and newer style indication lamps are used on the panel.


Heretaunga Non-Stopping Button. A button on the panel allows the signalman to initiate earlier starting of the Sutherland Avenue alarms for non-stopping trains.


Switches. The signal and points switches on the Trentham - Upper Hutt section of the panel differ in operation and relative position from those on the Upper Hutt - Featherston section.

Control Codes

Control Codes. Indicators are provided to show when control codes are being sent and indications received.


Signal Panel Layout describes the configuration of the panel.


FAQ Probably *not* Frequently Asked Questions but it is convenient to refer to the questions and answers as a FAQ!

Last Updated: Sun Mar 11 10:39:55 NZDT 2007

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