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(d) The FPL may be fitted nearer to the closed switch rail leading to higher
speed movement.

12.4.2 Notches: Notches in stretcher blades shall be cut clean and square and to
correct size.

12.4.3 Facing Point Lock - Plunger Type

(a) Facing Point lock plunger shall be square ended and installed 12 to 20
mm clear of the stretcher blades when the points are unlocked.

(b) The plunger shall have a stroke of at least 150 mm.

12.4.4 Obstruction Test: Facing point locks shall be tested by 'obstruction test' with
a test piece of 5 mm thickness placed between the switch and stock rails at
150 mm from the toe. With the obstruction in, it shall not then be possible for
the lever working the facing point lock to be latched.

12.4.5 Switch and lock layouts are not permitted in new installations. Spring point
levers self-reversing shall be installed in accordance with approved plan.

Section 5: Location of Signals in Mechanical Signalling

12.5.1 Placement of Signal

(a) Signals shall be so located that they do not infringe the Schedule of
Dimensions. Deviations shall be sanctioned by the competent authority.

(b) Signal posts shall normally be on the left side and adjacent to the line to
which they refer, and signals shall be located so that they are normally on
the left of, or above the line to which they apply, unless authorised by
special instructions.

(c) Signals shall be inspected by a Signal sighting committee consisting of
officials of Signal, Traffic and Mechanical/Electrical Departments before
being brought into use.

12.5.2 Fixed Green Light of Warner Signal: The fixed green light above a Warner
Signal on a post by itself shall be provided and shall be repeated.

12.5.3 Fixing Signal arms:All signal arms shall be fixed on the left hand side of the
post.

12.5.4 Placement of Warner Signal: A warner Signal may be placed, either

(a) on a post by itself with a fixed green light by night 1.5 meters to 2 meters
above it at an adequate distance (not less than 1200 meters unless
otherwise permitted by approved special instructions) outside the First
Stop Signal or Gate Stop Signal; or

(b) on the same post, but 1.5 meters to 2 meters below the arm of the outer
Signal; and

Chapter 12: Installation, Testing & Maintenance of Mechanical Signalling Equipment Page 240 of 535