Page 479 - IRSEM_Main Book

Section 3: Maintenance of Automatic Signalling Section

20.3.1 LED signal lamps shall be replaced in case of failure/after completion of codal life.

20.3.2 Marker light shall be replaced on age cum condition basis.

20.3.3 The following shall be tested by the SSE/JE (Signal) at least once in a year:

(a) Track Circuit control on signal and aspect control by signals in advance;

(b) Automatic Cutting-in of the next restrictive aspect when the LED aspect of
the main signal fails;

(c) Interlocking equipments and circuits for level crossings and points;

(d) The circuits that establish the direction of traffic in Single Line and prevent
clearing of conflicting signals on sections provided with Automatic block
Signalling on Single Line;

(e) Axle Counter resetting circuits, if provided.

20.3.4 All failures reported by the Loco Pilots/Motor man shall be promptly attended.

20.3.5 Track Circuits/Axle Counter Maintenance

(a) Adequate precautions should be taken after every track renewal work to
ensure proper working of track circuits/Axle counters.

(b) Provisions contained in Chapter 17 of SEM shall be adhered to.

20.3.6 Power Supply: Provisions contained in Chapter 16 of SEM shall be adhered to.

20.3.7 Cables: Provisions contained in Chapter 15 of SEM shall be adhered to.
Section 4: Modified Semi-Automatic Signalling Working

20.4.1 (a) Under special instructions, one of the automatic stop signals between two
stations in the automatic block signalling territory on Double Line may be
made as modified semi-automatic stop signal in each direction. During
abnormal conditions like fog, bad weather impairing visibility, Modified Semi-
Automatic Signal may be worked by extinguishing ‘A’ marker in the manner
prescribed under special instructions and this section shall also ensure that
the ‘A’ Marker of the Advanced Starter Signal of the station in rear and
Home signal of the station in advance shall also be extinguished. (Provisions
as per para 9.01 of GR shall be ensured.)

(b) Interlocking will be such that during mid-section Modified automatic signal
working with ‘A’ marker extinguished, not more than two trains, one on either
side of this modified stop signal, will be ensured by the signalling system
between two stations in any given direction at any given point of time. The
mid-section modified semi-automatic stop signal shall when ‘OFF’ depict the
aspect (Green or Double Yellow etc.) based on the aspects and number of
Automatic signals (including any other signal) between this signal and the
Home signal of the receiving station.

Chapter 20: Automatic Block Signalling Page 425 of 535