Document - irpmu.railnet.gov.in

3.1 DESIGN
i) Standards to be followed: All designs shall be prepared on CAD following General
Signalling principles and North Central Railway practices.
ii) The application data, Interface diagrams of the existing EIs, circuit diagrams of existing
interlocking will be made available by the Railways.
iii) The contractor should have at least 2 levels of internal check, production check and
Independent check followed by review of design at Design manager’s level before
submitting design for IRPMU’s approval.
iv) All the designs – application data and Interface diagrams of EIs, circuit alterations of
existing interlocking – will be approved by IRPMU. The onus of delivering safe design
will, however be of the contractor. IRPMU’s role will be limited to ‘in principle’ approval
only.
v) If any design deficiency is noted at any stage before and after commissioning (within
warranty period) due to any reason whatsoever, the contractor will arrange to correct/alter
the changes, install, Test (FAT & SAT) and commission the changes free of cost.
vii) The above guidelines would be applicable while designing application data and database
design for VDU at stations.
3.2 INSTALLATION TESTING & COMMISIONING
3.2.1 INTERCONNECTION/WIRING
Wiring of relay racks shall be carried out as per Interface diagram prepared by the contractor
and approved by the Railways.
Interconnection between terminal racks / boards and relay racks shall be carried out by
providing ladder arrangements/using existing ladder arrangement or by any other arrangements
as instructed by Railway representative.
It shall be possible to identify wires to all terminals by means of non- metal tag corresponding
to the circuit and wiring plan. Contractor may adopt any other means subject to approval of the
Railways. Tag shall be applied in such a manner that if a wire is removed from the terminal,
the tag will remain on the wire.
Where practicable the tags or labels shall be securely fastened adjacent to the terminals or
suitably painted so that the number can be easily read.
Contact numbering for the relays shall be made by the contractor as per the circuit diagram
approved by the railway and type of relay proposed to be used on the installation.
No joints are permitted in the connection wires.
Signature of contractor Page 16 of 104 Dy CSTE/Proj/IRPMU/CNB