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THE WEST SOMERSET RAILWAY
A Description of the Signalling by Kevin Weston
Blue Anchor
Blue Anchor is the other signal box on the
branch that retains most of its original equipment. It is of brick construction
and the opening date is generally given as 1904. The layout is simple, a
crossing loop with a siding at the Minehead end. Three camping coaches are
parked on the siding, although the point was disconnected when the line
reopened. Some of the equipment in use dates from the opening of the signal
box. There is a road crossing at the Minehead end, protected by wooden gates
operated by a wheel in the signal box. This is the last set of original GWR
gates in use; all the others on Railtrack have been converted to barriers. It
is known that the crossing was rebuilt in 1955, we have the drawings for this
work and they indicate that the operating mechanism was overhauled but not
altered. The road approaching the crossing from the sea front is on a sharp
bend and, despite the 30 miles per hour speed limit; some car drivers still
come around the bend too fast and find the gates across the road. The gates are
hit at least once a year and the drivers have some original excuses. One of the
best was on a summer evening; a train from Minehead was in the process of a
run-round move when a car hit the gates, the driver complained that the
accident would not have happened if we did not run trains in the evenings. The
point at this end of the loop is operated by the original rodding, although it
is possible that the point was moved about 20 yards in 1934. This was the date
that the loop was lengthened at the Williton end. The Minehead end point
retains its original fouling bar for the FPL; the one at the Williton end of
the loop was converted to motor operation in September 1995, using a
reconditioned Westinghouse Style M3A machine with track circuit locking. Some
of the volunteers had complained about the use of this modern equipment, but
they have been reminded that this modern equipment, based on a
1930s design, is older that some of the steam engines they drive.
All the signals are BRWR design, erected around the same time as
those at Williton. When the branch closed in 1971, all the internal equipment,
apart from the lever frame, was removed. This equipment had to be replaced
before the signal box could be reopened. The frame has 17 levers with Stud
locking and is dated 1903, indicating that it was constructed in Reading Signal
Works before the signal box was built. It is believed that this frame is the
oldest of its type still in use in the signal box for which it was designed.
Railtrack has only one original Stud frame still in use, while several of the
other private railways have used reconditioned Stud frames. Token working to
Minehead was introduced in 1990 when the signal box there was opened. The WSR
has no signalling cable between the two signal boxes; the token operates over a
dedicated British Telecom line using a system of ac frequency signals. Six
frequencies are required to operate the system, which must ensure that only one
token can be removed at any time. While the signal box and station may give the
appearance of a country station in the 1950s, it is an interesting mix of
equipment, the modern electronic system for the token is working along side
mechanical interlocking designed nearly a hundred years ago.

Not all the siding connections are controlled by a signal box but
the Railway Inspectorate still require that all facing points on a passenger
line are fitted with a Facing Point Lock. Within the control of a signal box,
the FPL is either locked electrically through the lever lock or by a mechanical
fouling bar. In a block section, some other means is required to interlock the
point with the train staff. The normal method of operation is to provide a
small ground level lever frame to operate the points. The levers are locked in
the normal position and can only be released by a key attached to the train
staff. The key is retained in the lock while the points are operated and can
only be removed when the point levers are returned to normal. At the present
time there are two intermediate ground frames, one at Dunster and one at
Washford.
Level Crossings
Williton and Blue Anchor were the only signal boxes in use when
the WSR began passenger services in 1976. There are also four road level
crossings, which are not located at signal boxes and are not, therefore, under
the control of a signalman. Until closure of the branch, crossing keepers had
been employed to operate the gates and protecting signals at three of these,
while the fourth crossing at Dunster West was under the control of a signal
box. The railway at that time was operated entirely by volunteers, and there
was no one available to work these crossings. The solution was to convert them
to automatic operation. There was no requirement of both tracks to Minehead for
passenger trains and it was decided not to reopen Dunster signal box,
fortunately, the Railway Inspectorate gave permission for Dunster West Crossing
to become Open, i.e. no signalling required. The others, at Sea
Lane (Dunster East), Leigh Woods and Roebuck required road lights and rail
signals. Approaching trains are detected by track circuits, which are long
enough to give the road users sufficient warning of the fastest train. The line
speed on the WSR is 25mph but the design of the crossings has allowed for 40mph
trains slowing down to 25 mph over the crossings. A standard road light unit
for level crossings has a steady yellow for five seconds followed by two
alternate flashing reds. Two of these units are provided on each side of the
crossing. On the rail side, the driver will see a flashing white light when the
flashing red road lights are operating but must look out for road users
jumping the lights. If there is no flashing white, the train must
stop before passing over the crossing and the fireman will hand-signal the
train when the crossing is clear. New crossings now require a flashing red
light to be exhibited to the driver when the flashing white is not shown.
At Watchet, the railway has a very busy footpath crossing between
the town and the sea front. Miniature red and green warning lights are provided
for indicating to pedestrians. A track circuit and a treadle in each direction
detect the approach of trains. This is the only location where ac track
circuits are used, standby power in provided by a 24-volt battery through a
dc/ac inverter.
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