Page 512 - IRSEM_Main Book

Section 4: Electronic Interlocking (EI)

21.4.1 Essential Requirements of Electronic Interlocking

(a) Electronic Interlocking System shall be approved type and shall conform to
latest approved specification.

(b) Electronic Interlocking System shall have the highest level of safety
integrity as stipulated.

(c) Electronic Interlocking System shall be suitable for working on Electrified
and Non-Electrified sections.

(d) Electronic Interlocking System Installation shall be of Route setting type
using Dropdown menu Or Entry/Exit control with a facility for individual
operation of points.

(e) Signalling and interlocking arrangements for the Yard shall be in
accordance with the approved Signal Interlocking plan (SIP) and Control
Table.

(f) Electronic interlocking system shall be capable of working with Control
Panel or/and Control Terminal.

(g) Electronic Interlocking system shall have adequate built-in redundancy as
per approved specification.

(h) Provisions given in Sections 1,2 given above are generally applicable for
Electronic Interlocking also.

21.4.2 Control Terminal (Video Display Unit (VDU))

(a) Same requirements given in Para 21.1.1, 21.1.2 shall apply for existing
Control Panels (where provided) for Electronic Interlocking(E.I)
installations. Control Panels shall not be used in future Electronic
Interlocking installations.

(b) Control Terminal/multiple Control Terminals shall be of appropriate size to
display layout of the Yard in well-proportioned dimensions and shall
display all functions clearly distinguishable. Normally Control
Terminal/multiple Control Terminals shall be provided in redundant mode.

(c) Video Display indications on Control Terminal shall conform to Control
Panel indications as covered in Para 21.1.4 or other approved type.

(d) Operation of Signals, Points and other Controls such as Gate, Crank
handle, Siding, Slot etc. shall be carried out through appropriate dropdown
menus or other approved means.

(e) Control Terminal shall have suitable protection facility against
unauthorized operation which may be provided by physical ‘SM Key’ in a
separate box and key contacts are taken to pick up two separate ‘SM Key’
relays in relay room for redundancy purpose. These relay contacts are
taken as input through two different input cards preferable in different OC’s
and ‘SM Key IN’ bit shall be made by their parallel proving inside E.I.

Chapter 21: Relay & Electronic Interlocking Page 455 of 535