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GWR Route: Hatton to Bearley and Alcester Branch
Bearley Station: gwrbj2349
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View of the other of the side of the Bearley East Junction
to Bearley North Junction single line key token. The staff and ticket system
was still too inflexible for busy lines, as it did not allow for the situation
where the train intended to carry the actual token was cancelled or running
very late. To provide for this, the electric train token system was developed.
Each single-line section is provided with a pair of token instruments, one at
the signal box at each end. A supply of identical tokens is stored in the
instruments, which are connected by telegraph lines. A token can be removed
from one instrument only if both signalmen cooperate in agreeing to the
release. Once a token has been removed, another cannot be removed until the
token which is "out" is replaced in either instrument. (There are variations on
this sequence of events.) By this means, it can be ensured that at any one
time, only one token is available to be issued to a driver. Tokens belonging to
adjacent sections have different configurations to prevent them being inserted
into the wrong instrument. Nevertheless, in the Abermule train collision in
1921, lax working procedures allowed the safeguards provided by the electric
token system to be circumvented; a driver was handed a token for the wrong
section, and proceeded on the mistaken belief that the token was correct. To
prevent this, it is now a requirement in the UK for the signals controlling
entry to the single line section (starting or section signals) to be locked at
danger unless a token has been released from the relevant token instrument.
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