Page 315 - IRSEM_Main Book

12.27.2 Date of last Overhauling and Testing

(a) Date of last overhauling and testing shall be painted on the lever frames,
interlocking key boxes and Station Master's slide control frames.

Section 28: Testing and Overhauling of Electromechanical

Installations

12.28.1 Mechanical Locking

(a) Instructions contained in the preceding paragraphs for the installation,
maintenance, overhauling and testing of locking of mechanical interlocking
frames shall also apply to electromechanical installations with mechanical
locking frames wherever relevant.

(b) The mechanical locking of interlocking frames shall be tested for lost
motion, as per para 12.1.3(i) and lost motion, when in excess of the
prescribed limits, shall be removed.

12.28.2 Electrical Locking

(a) In electromechanical installations electric lever locks, key transmitters,
circuit controllers, Detectors etc. shall be provided as per approved plan.

(b) Diagram of electrical circuits for each such gears shall be prepared and
shall show all the necessary controls which shall be required to release a
particular lever.

(c) Where lever locks have been provided in the mechanical lever frames for
controlling operation of Electric Point Machine, Electric Signal Machine or
for route holding etc the functioning of the same shall be tested.

(i) Points Lever: In points lever ABDE locks are provided for Track &
Indication locking. Lever shall be tested to ensure that the lever lock is
energised and the lever is free to be operated in A/E position only
when the controlling tracks are clear. The lever shall again be locked
in D position when the point is being operated from normal to reverse
and lever shall be free only when the points has operated fully and
locked and detected in reverse position. Similarly, while operating the
lever from reverse to normal the lever shall be first locked in E position
to ensure track locking and subsequently will be held at B position for
point operation. The lever lock shall not energise at B position unless
the points have operated, set, locked and detected in normal position.

(ii) Signal Lever: While pulling the signal lever from normal to reverse
the lever shall be locked in A position and will be free only when route
for the reception of the train has been correctly set, all facing points
locked and all the controlling tracks are clear i.e. all conditions are
fulfilled for taking 'OFF' the signal. While putting back the lever from
reverse to normal position the lever shall be locked at B position and
will be free only when the intended movement is completed and it is
free from back locking as well as approach locking where provided.
Normal indication locking must also be effective in B position in case
of semaphore signal.

Chapter 12: Installation, Testing & Maintenance of Mechanical Signalling Equipment Page 269 of 535