Page 384 - IRSEM_Main Book

(g) Rail ends shall be kept free from brake-dust, dirt, sand, rust, other foreign
materials etc. All rough edges and burrs at rail ends must be removed.

(h) To avoid crushing of end posts of insulated rail joints due to creep, at least
one rail length on either side of insulated joint should be provided with anti
creep devices.

(i) Rail screws should preferably be used in place of dog spikes at insulated
joints.

Note: The requirements mentioned in the para no. 17.1.2(a) to (i) are covered in
the chapter II, Part "H" of Permanent Way Manual.

(j) Wooden sleepers, concrete sleepers or any other approved type of
insulated sleepers shall be provided for track circuiting. Concrete sleepers
where used, shall have a minimum resistance of 500 ohms between insert
to insert.

(k) Where short welded rail panels are used, SWR shall not butt against
insulated joint. Two rail lengths of 13 meters/12 meters shall be interposed
to isolate short welded rail from insulated joint. This standard length of
rails shall be anchored effectively to arrest movement in either direction.

(l) In case of turnouts and crossings, insulated stretchers, insulated gauge tie
plates and insulated crossing plates shall be provided as per approved
drawings.

(m) GFN liners shall be provided in the track circuited area using concrete
sleepers.

(n) Track circuited area shall be free of vegetation. Only insulated trolleys
shall be used.

Section 2: Installation of DC Track Circuits

17.2.1 Location of Track Relays

(a) Track relays shall be located at the entry end of the track circuits wherever
possible.

(b) Where track relays cannot be located in the cabin/Relay Room, they shall
be housed in locations of an approved type.

(c) Where relays are likely to be subjected to vibration, suitable anti-vibration
measures may be provided. They shall be mounted on shock absorbers
such as rubber pad, foam etc.

(d) Connections between the track relays and track repeating relays shall be
made in accordance with the approved wiring diagram and must invariably
incorporate both cross protection and double cutting arrangements.

(e) The feed and relay ends shall be connected by separate and individual
cables.

Chapter 17: Train Detection Track Circuits & Axle Counters Page 332 of 535