Colour Light Shunt Signals

The same set of rules applies to all colour shunting signals (ground lights) but the way they opperate can differ. In this page I describe the rules and then, using the three ground lights at Petone as an example, I explain some of the differences in operation.

(Opposite) Signal 1518 at Woburn North Sidings was fixed red, situated next to a Shunting Limit Board. The signal has since been removed.

Shunt signal Woburn North Sidings

Colour Light Shunt Signals - The Rule Book

Shunt Signals

Shunt Signals At Petone

There are three shunt signals at Petone and they each behave differently.

Petone shunt signals

68 Shunt and Down Starting from Up Main

Three position.

Low speed to Down Main clear.

Requires the overlap (66T) clear as well as the section clear to display Caution.

Approach lock timer 30 seconds (delay when 10T occupied).

Classified as a Starting Signal.

8 Shunt from Down Main

Three position.

Low speed to Down Main occupied or Up Main occupied or clear.

The concept of an overlap is not relevant because the signal displays Caution to the up main occupied.

Approach lock timer 60 seconds (delay when 67T occupied).

73 Shunt from Up Main

Two position.

Low speed to Up Main occupied or clear.

Last wheel replacement.

Approach lock timer 60 seconds (delay when 14T occupied) - maybe not relevant now that 43 & 44 points have been removed).

Last Wheel Replacement

Last wheel replacement

A Wairarapa train sets back to Petone Sation under the authority of 73 Shunt from Up Main signal. Both Up and Down mains were blocked after a down EMU became tangled in the overhead. Although the rear of the Wairarapa train has passed 73 signal it is still showing Caution - Low Speed. The signal will go to stop after the locomotive has passed it. The section is occupied - an EMU (not visible) is berthed at the Wellington end of the Up platform.

Signal 68

The three aspects of signal 68 at Petone.

Signal 68 Petone Signal 68 Petone - caution Signal 68 Petone - Clear


Stop - the track is occupied or for some other reason the train should stop.

Caution - Low Speed

Proceed at low speed, prepared to stop. Points are in the correct position but track is occupied, or suitable for low speed only.

Clear - Low Speed

Proceed at low speed. Points are correctly set and track is clear, but suitable for low speed only, and signal next in advance is at "Caution" or "Clear".

Signal is classified as a Starting Signal so Normal speed may be resumed when clear of points.

Last Updated: Sat Aug 15 12:54:16 NZST 2009

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