Section 11: Indicators and Signs associated with Points

(Page 2 of 2)

The development of new signalling systems employing simplified infrastructure and train-operated (hydro pneumatic) points brought about a new requirement to have points indicators on running lines. In April 1984, the crossing loops at Garve and Arisaig on the Scottish Region were provided with simplified infrastructure in preparation for the eventual provision of Radio Electronic Token Block (RETB) over the routes concerned. The points at each end of the loops became train-operated and points indicators were provided, applicable to facing moves over those points. When the points are set correctly, the yellow light in the indicator will be illuminated [11.27]. If the light is out, the driver must stop and not pass over the points until they have been secured.

[11.27] 'Points Set' Indicator - Points set correctly (Scottish Region).

With a desire for cheapness and simplicity, the British Railways Board in London had proposed that the standard form of points indicator for future works should be mechanically operated. Normally this indicator would display a diagonal black stripe [11.28], indicating that the points to which the indicator applies are set correctly. When the face of the indicator was rotated such that the black stripe was horizontal [11.29], it indicated that the points were not correctly set. One of this type had been installed at Bedford St. Johns (London Midland Region) before being transferred to the west end of the loop at Strathcarron in June 1984. Since it could not be made to work properly, electrical indicators normally displaying a yellow light were installed (see [11.27]). Given the availability of power supplies for platform lighting and points heating, it was decided that electrical indicators would be provided as standard in future.

[11.28] Mechanical 'Points Set' Indicator ('off').	[11.29] Mechanical 'Points Set' Indicator ('on').

Another new signalling system to use simplified infrastructure and train-operated points was known as "No Signalman Key Token Remote" (NSTR). This system was pioneered on the Central Wales Line (Western Region) in 1986. Unlike the RETB system, with NSTR there is no means to ensure that a train has departed a crossing loop before a following train is allowed to approach the same loop. With this in mind, it was considered that rather than show a yellow light, points indicators on NSTR lines should show a position light aspect (two white lights at 45°) [11.30]. When the Whitby line (Eastern Region) was converted to the NSTR system in 19__ however, points indicators showing the usual yellow light were provided [11.31].

[11.30] Points Indicator - Points set correctly (NSTR lines).	[11.31] Points Indicator - Points set correctly (Eastern Region).

In 1987 and 1988, at certain locations on the Scottish Region, the train-operated points were altered to normally lie the opposite way. This was done to ease shunting at those places, but had the side effect of imposing right-hand running through the crossing loops. To remind drivers that the train-operated points lie normally to the right, a supplementary arrow sign was added to the relative 'points set' indicator [11.32].

[11.32] 'Points Set' Indicator with supplementary arrow sign.

The 'points set' indicators used on the Cambrian Lines RETB scheme (London Midland Region) had the yellow light set against a large white board [11.33].

[11.33] 'Points Set' Indicator - Points set correctly (London Midland Region).

In 1987, fouling point markers were provided at crossing loops on the West Highland Lines (Scottish Region) pending the introduction of RETB. These comprised an orange cylindrical marker with a white stripe [11.34] provided at ground level between the loop lines at each end of a crossing loop. These were provided to allow trainmen to determine whether their train was within the fouling point.

[11.34] Fouling Point Marker (Scottish Region).

In c.2001, at Selhurst Depot, certain key fouling points were identified by painting sleepers orange.

The 'remote ground frame marker' [11.35] was introduced in 1996 as part of a proposal aimed at warning drivers in the event of detection being lost at ground frame operated points in remote areas. The marker would be positioned on the approach side of the points applicable to moves in the facing direction. A colour light distant signal would be provided at braking distance on the approach side of the marker. If detection of the points was lost, the distant signal would display a yellow aspect (see [2.93]), and trains would then require to be stopped at the marker board. Similar signs may be seen at facing points on French railways, but they serve a different purpose. Provision of the remote ground frame marker board was discontinued from 1999.

[11.35] Remote Ground Frame Marker.

In 1997, mechanical points indicators were provided at Welbeck Colliery, associated with the ground frame operated points at either end of the run-round loop. Separate points indicators were provided for both the facing and trailing directions. Although similar in appearance to 'yellow' disc shunting signals (without lights) [11.36 & 11.37], their meaning was quite different. In the 'proceed' position [11.37], the disc indicates that the points have been operated to the appropriate position, and in the case of facing movements, that they are locked.

[11.36] Points Indicator ('on').	[11.37] Points Indicator ('off').

In 2003, signal MB298 on the Down Arrival Line at Mossend Yard was provided with an additional miniature indicator. When the signal is cleared for a route to the Down Yard, the indicator shows a left-hand or right-hand arrow (along with the route indication "Y") to indicate the lie of the facing handpoints ahead [11.38]. The same arrow indication is repeated at the points themselves.

[11.38] Handpoints Indication (e.g. points set to left).

In 2003, the original fouling point markers on the West Highland Lines (see [11.34]) were replaced by new markers in the form of a plain yellow post [11.39]. Ironically, just a few days after the markers were replaced, a Class 156 'Sprinter' struck the rear end of a steam-hauled empty coaching stock train that was stopped foul of the loop points at Glen Douglas on 12 June 2003.

[11.39] Fouling Point Marker (Scotland Zone).

Some of the American-style handpoints in Bescot Yard are of the non-trailable type. The switch stands that control them have been fitted with indicators to allow the shunter to determine from a distance which way the points are lying. When the points are in the 'normal' position, a white arrow pointing up on a blue background is displayed [11.40]. In the 'reverse' position, the indicator shows a black arrow pointing left or right, on a white background [11.41].

[11.40] Switch Stand Indicator Sign - Normal.	[11.41] Switch Stand Indicator Sign - Reverse (e.g. points set to left).

In 2006, ground mounted points indicators were installed on each approach to a particular set of points at Kings Heath Traincare Depot in Northampton. Separate indicators were provided for both the facing and trailing directions. In common with the earlier forms of electrical points indicators, a yellow light is exhibited when the associated points are in the correct position (see [11.31]). The new indicators comply with the latest standard that requires a red light to be exhibited when the points are incorrectly set [11.42]. This provides a positive 'stop' indication, in contrast to the earlier indicators where no light meant 'stop'.

[11.42] Points Indicator - 'Stop' indication.

Home Page