Page 375 - IRSEM_Main Book

Chapter 16: Power Supply Systems for Signalling Installations

Section 1: Power Supply General

16.1.1 Power supply for different types of signalling installations shall be in accordance
with policy approved by the Principal Chief Signal and Telecommunication
Engineer of the Railway, if standard power supply scheme from Railway
Board/RDSO is unsuitable for a specific application.

(a) At all locations, secondary batteries of appropriate capacity shall be
provided for signalling circuits.

(b) Normal power supply for signalling installations shall be 230 V AC (single
phase) or 415 V AC three phase. Any other supply may be used with the
specific approval of the Chief Signal and Telecommunication Engineer
incharge of the work.

(c) Power supply system shall be such that fixed stop signals for approaching
train do not become blank when main power supply source fails.

(d) Power supply system with secondary batteries of approved type and
adequate capacity shall be used for signalling applications.

Section 2: Sources of Power Supply

16.2.1 Railway Electrified Area
(a) Electric supply for signalling and telecommunication installations in RE
areas shall normally be provided through Auxiliary Transformers (ATs) of
suitable capacity by tapping 25 KV OHE.

(b) On double/multi line sections, the power supply shall be drawn from 25 KV
OHE through ATs provided on up and down OHE lines separately. It shall
be ensured that supply from at least one AT is available in the event of
power block.

(c) On single line section where power supply is drawn from a single AT, a DG
set of suitable capacity shall be installed.

(d) At stations where local power supply is also available, it shall act as a
stand-by source of power supply.

(e) In big yards, DG sets of adequate capacity shall be installed in addition to
supply from ATs and local source.

(f) The power supply from Auxiliary Transformers (ATs), local source and DG
set (s) shall be brought and terminated at a power supply control panel in
ASM's office/cabin or at LC gate as required. The power supply control
panel shall be provided with the facilities for automatic change over
between source supplies. In addition, manual change over facility shall also
be provided in the control panel. The power supply control panel, in coming
cable (other than from DG set) and other associated arrangements shall be
provided and maintained by Electrical Dept.

Chapter 16: Power Supply Systems for Signalling Installations Page 323 of 535