NATIONAL ALUMINIUM COMPANY LIMITED - Rites

Bidder shall consider earthing ring mains at each electrical premise and connect the electrical
equipment with the rings. The earthing ring mains shall be connected with underground
earthing mats to be provided by the bidder made of 2x40mm dia solid MS rod. Adequate
number of risers shall be made available for connection with his earthing ring main. For
transformer neutral earthing, bidder shall consider dedicated plate earthing.
Lightning protection shall be provided by the bidder for complete WT SYSTEM including tall
installations covered under the battery limit.
Bidder shall also include complete illumination of the premises under the battery limit and all
the above electrical premises coming at WT SYSTEM substation and adjoining areas.
Air-conditioning, conditioning, ventilation and exhaust fans for various rooms / premises of WT SYSTEM
along with their complete electrics shall be under scope of the Bidder. The battery and battery
charger room shall be air- conditioned. Switchgear cum MCC room of WT substation shall have
pressurized ventilation. Transformer rooms of the WT substation shall have exhaust fans fans.
All interconnection for power, control and instrumentation/signal amongst equipmen equipment
supplied by the Bidder shall be under Bidder's scope of work. Similar interconnections
including power, control and signal between Purchaser's equipment and Bidder's equipment
shall be done by the Bidder. All the cable terminations at both ends, cable tr trays and cable
accessories shall be under Bidder's scope.
2.5 Electrical system design criteria
a) General
The design, manufacture, assembly and testing as well as performance of the equipment shall
conform to the relevant IS : specifications (latest revision) and other relevant standards. In
case IS specifications is not available in respect of certain items, the Bidder may base his
proposals on IEC/BS/VDE/DIN recommendations or other reputed national or international
standards subject to the approval of the Purchaser Purchaser/RITES. . All equipment supplied and all work
done including system design and detailed engineering shall also comply with the statutory
requirements of the Government of India and the Government of Orissa.
b) Climatic Conditions
Electrical Equipment selection and derating shall generally be based on ambient temperature
of 50 o Electrical Equipment selection and derating shall generally be based on ambient temperature
C. The equipment offered shall be suitable for smooth, efficient and trouble free service
in the climate prevailing at Angul.
c) Standard Voltage levels
Technical Specification:Sec-6, Electrical
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