Page 546 - IRSEM_Main Book

Para No. 22.8.4(b) Annexure: 22-A2

Maintenance in Electrified Areas

(Extract of part 'J' of Permanent Way Manual PART 'J')

282 General Instructions to Staff: -

1) General Knowledge of Engineering Staff

(a) Every Engineering official working in electrical traction area shall be in possession of a
copy of rules framed for the purpose of the operation of the Traction Power
Distributions System pertaining to Engineering Department and ensure that staff
working under him are also acquainted with the rules. He will ensure that rules
pertaining to carrying out engineering works are strictly observed.

(b) All electrical equipment, every power line or cable shall be regarded as being 'live' at
all times. No work shall be commenced adjacent to any electrical equipment except
on authority issued in writing by a competent official of the Electrical Department to
the effect that the equipment has been made dead and earthed.

2) Defects in Overhead Equipment: Defects or break downs in the overhead equipment
including track and structure bonds noticed by the Engineering staff shall be reported
immediately to the Traction Power Controller. When defects in the overhead equipment
that are likely to cause damage to pantographs or trains are noticed, and it is not possible to
convey information to Station Masters or Signal men to enable them to issue caution orders,
the line shall be protected by the staff noticing such defects according to General Rule 3.62.

3) Traction Bonds: In electrified areas the return current fully or partially flows through the
rail. To ensure a reliable electrical circuit continuity and also to ensure proper earthing in
case of leakage of current, various types of traction bonds as described below are provided
at suitable places and maintained by the Electrical Traction Department: -

(a) Longitudinal Rail Bonds: In the case of D.C. traction system, practically the whole
return current flows through the rail. Therefore, two flexible copper bonds offering
minimum resistance to the flow of current are provided at each rail joint under the
fishplates. Two solid lugs at the two ends of the copper bonds are inserted in holes
drilled at the two rail ends between the fish bolt holes and are pressed by using a
bend press to rivet them firmly to the rails. On points and crossings and at junction
fishplates where continuity bonds of the above type cannot be provided due to space
constraints, continuity of return current path is achieved by using mild steel straps or
G.I. wire ropes.

Absence of such bonds may cause unsafe working condition and in extreme cases
may damage the rail ends.

(b) Cross Bonds (D.C): Cross bonds are provided between adjacent tracks at regular
intervals to reduce resistance of the current to the minimum. Such cross bonds are
also known as transverse bonds.

Chapter 22: Requirements Of Signalling In 25 KV AC Electrified Area Page 489 of 535