VADODARA JAL SANCHAY PRIVATE LIMITED 42 MLD TTWW Recycle Plant
4.5 MEDIUM VOLTAGE BUSDUCTS - ALUMINIUM SANDWICH TYPE BUSDUCT
SCOPE:
➢ This specification covers the design, manufacture, testing , installation, and commissioning of
Aluminium busbar sandwich type bus duct. The proposed bus duct will serve as
interconnection between MV terminals of outdoor transformers to their respective MV
Switchgears.
CONSTRUCTION REQUIREMENT:
➢ Bus duct shall confirm to IEC 61439 (1&6) & IS 8623 (1&2); with latest amendments. Fault
level of the busduct shall be 65KA for 1 sec. Design ambient temperature: 50deg C.
415 V, 3phase AL + 100% neutral AL + 50% Internal Earth (AL) + External earth, naturally
cooled, totally enclosed sandwich type busduct of aluminiumbusbar, GI Enclosure, powder
coated Siemens grey RAL-7035 , IP 65 suitable for outdoor application with suitable vertical &
horizontal bends, adopter box, expansion joint, suitable hardware as per IEC/ IS specification.
Wall frame assembly shall be used wherever Busduct penetrates the wall. Expansion joint shall
be provided for every 30 mtrs and as per site/route requirement.
The tenderers are requested to visit the site and acquaint themselves with the site conditions
before quoting. No extra claims will be entertained at a later stage.
ENCLOSURE:
➢ Enclosure shall be made up to Electro galvanized/ Hot dipped GI sheet of 1.6mm thick/ 2mm
thick aluminium. The degree of protection shall be IP65.
➢ Enclosure shall be weather proof, dust tight suitable for outdoor installation.
BUSBARS:
Rating: As per Incomer rating
Material: Aluminium ETP grade with high conductivity (99.5% pure)
Configuration: 3Phase + 100% Neutral + 50% Internal Earth (AL) + + External earth (Al)
Rated Insulation Voltage: 1000V AC.
➢ Maximum operating temperature at any point of the bus shall not exceed 85 deg C with the
limiting ambient conditions specified 50degC. Eddy current heating shall be taken into account
while designing the enclosure.
➢ Busbars shall be insulated with high strength, good quality insulating material/ coating class F/
Class H as per site condition and shall be colour coded at the ends for easy identification of
phases.
➢ Adjacent busbar sections shall be joined with separate sub-assembly so that they can be
inserted / removed easily without disturbing the sections.
➢ Copper flexible shall be provided at all the terminating ends. i.e at Transformer end and Panel
end.
➢ Phase sequence of Bus-bars shall be matched according to the transformer phase sequence
Earthing:
➢ Internal Earth shall be of Aluminium and cross section of the same shall be 50% of Phase /
Neutral busbar. Integral earth shall be connected to nearest earth pit / Earth busbar as per site
conditions.
➢ External Earth with 2 separate runs of GI/AL of size 50 X 6 shall be provided throughout the
length of the busduct and enclosure, supporting structure etc shall be connected to Earth/
Ground bus.
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VADODARA JAL SANCHAY PRIVATE LIMITED 42 MLD TTWW Recycle Plant
PLUG In Boxes:
➢ Suitable Plug in boxes shall be provided as per requirement.
➢ Busbartrunking shall be installed so that plugs are side mounted to permit practical use of all
plug-in openings.
➢ All contact on joint and plug-in opening should be silver plated copper.
It shall be possible to inspect the plug-in opening and bus-bars prior to the installation of the plug-
in units.
Supporting Structures
➢ Structure and foundation drawing duly certified by Busduct OEM after joint site measurement
shall be submitted for approval.
➢ All supporting structures required for hanging and / or supporting the complete bus duct shall
be included in the scope. This includes all members, indoor / outdoor posts, bolts, shims, base
plates, beams, hangers, brackets, bracings and hardware.
➢ All steel members shall be hot dip galvanized. All hardware shall be in SS.
➢ The enclosure supporting arrangement shall be such that the bus duct load is not transmitted
onto the terminations.
➢ The insert plate required to be embedded in concrete will be provided by contractor and further
anchor bolts, plates, members required to support the bus duct shall be included by the Bidder
as part of the structural material. Alternatively anchor bolts can be used in which case the bolts
shall be shipped in advance for grouting in civil foundation.
Documents to be submitted for Approval:
➢ GA drawing, Structural and foundation drawing, Busduct route layout, Termination (for
Transformer connection) details
4.6 LT PANEL – PCC / PMCC / MCC / APFC / OTHER LT SWITCH BOARDS
➢ Panel shall confirm to Indian Electricity Act and rules CEA Notification/ Guidelines, CPWD guidelines
2019 as amended up-to date and shall be as a minimum.
➢ The MV switchboard panels shall be floor mounting, free standing, compartmentalized, extensible,
Modular type suitable for indoor installation. The panel shall be totally enclosed and dust, damp &
vermin proof. Enclosure shall have IP-52 or better degree of protection for indoor unit & IP-55 or better
degree of protection for outdoor unit as a minimum. Outdoor unit shall be double door and additionally
provided with canopy or weather shed for protection.
➢ Panels shall be complying to Form-3b as per IS/IEC 61439. Only metallic sheet shall be used for
compartment separations / partitions, Hylam/PVC sheets shall not be allowed.
➢ PCC/PMCC panel shall have 2 nos. outgoing MCCB/ACB power feeders, one number on each side of
BUS to feed power to downstream MCC panel.
➢ All MCC feeders will have two incomers (One Incomer as stand-by) with electrical and mechanical
interlocking between the two such that only one incomer is ON at a time.
➢ MV switch boards sheet steel shall be CRCA mini. 2.0 mm for load bearing members, mounting plate,
partition, doors/covers, Canopy. Gland plate shall be CRCA sheet min. 3.0 mm thick. All the doors and
others openings shall be provided with neoprene rubber gaskets or of durable material gaskets.
➢ All hardware shall be corrosion resistant in SS. Star washers shall be used for effective continuity.
➢ Suitable lifting arrangement with L angle welded at top for PMCC/MCC/APFC etc. shall be provided
on each panel or on each shipping section for ease of lifting of switchboard.
➢ A base channel of 100mm x 50mm x5 mm thick shall be provided at the bottom of the panel on all four
sides of each shipping section.
➢ Overall height of Panel shall not exceed 2300mm (For VFD, Soft Starter panel height up to
Max.2500mm can be accepted) including min. 100mm ISMC base frame.. However, in case of panel
mounted on floor without cable trench shall be mounted at least 500mm above the floor level to provide
adequate bending radius for in & out cables.: Folding type stand of minimum height 500mm with
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