The power box was
commissioned as a series of phases as already mentioned; more details
and dates on this can be found in the section Preston
Signalling by David Ingham.
During the Stage 1 commissioning work Farington Junction box would
act as the link up box from October until November 1972, with the area
south under the control of the new power box, while the tracks north
would remain under mechanical control.
Stage 2 would take the south link north to Skew Bridge, until the
final Stage 7 work (February 1973).
The most northerly work was stage 6 carried out in January 1973.
Carnforth No.2 and Burton and Holme would remain in use until Stages 7
and 8 of Carlisle scheme were implemented over the weekend of the 12th and 13th May 1973. This would mark the conclusion of the
route to Carlisle.
The Stage 7 work was the Preston station area and linked the
northern (Oxheys) and southern areas, which had already been
commissioned, together. It took in the Fylde lines, with Salwick No.2
becoming the fringe box.
This only left East Lancashire to be completed.
Strand road box became a ground frame and the Deepdale branch at
the former Preston No.5 end, now came under the control of the power
Between Weaver Junction and Gretna a total of 811 signals were
required, along with 562 miles of telecoms cable.
The sheer scale of the re-signalling project at Preston really has
to be admired, it was the largest installation of the three power
boxes, here are a few statistics:
Manual signal boxes abolished 87
Fringe boxes and token stations 11
Colour light signals 466 (254 Warrington 325 Carlisle)
Routes signalled 866 (232 Warrington, 553 Carlisle)
Point Machines 364
Track Circuits 1050
Route miles 114
Track miles 263 (145 Warrington 221 Carlisle)