corrigendum tender for puf insulated hdpe drinking water tanks , pre- insulated ppr pipe , pre-insulated ppr pipe fitting , joint kit , self-regulating heat tape , copper cable , distribution panel , earthing , lightning arrestor , itc, anti freezing system for water supply in high altitude region of sikkim, 500 litre capacity multi-layered hdpe tank as per specification document, 750 litre capacity multi-layered hdpe tank as per specification document, 1000 litre capacity multi-layered hdpe tank as per specification document, company-fitted pre-insulated ppr pipe, size 25 mm (pn20/sdr 6 carrier pipe, 40mm rigid puf insulation core, uv-stabilised 110mm outer dia, 2.5 mm thick hdpe outer jacket with integrated guide channel)., company-fitted pre-insulated ppr pipe, size 32 mm (pn20/sdr 6 carrier pipe, 40mm rigid puf insulation core, 125mm outer dia, 3.0 mm thick uv-stabilised hdpe outer jacket with integrated guide channel)., pre-insulated plain equal tee fittings (ppr core with factory matching puf/hdpe outer shell encapsulation) 25/32 mm, pre-insulated plain reducing tee fittings (ppr core with factory matching puf/hdpe outer shell encapsulation). 25/32 mm, pre-insulated 90 degree plain elbow fittings (ppr core with factory matching puf/hdpe outer shell encapsulation). 25/32 mm, pre-insulated 90 degree brass threaded female elbow fittings (ppr core with factory matching puf/hdpe outer shell encapsulation). 25/32 mm, pre-insulated plain reducer compatible with pre-insulated pipe and water tank inlet/outlet connections. 25/32 mm, pre-insulated plain union compatible with pre-insulated pipe and water tank inlet/outlet connections. 25/32 mm, pre-insulated plain socket compatible with pre-insulated pipe and water tank inlet/outlet connections. 25/32 mm, pre-insulated brass-threaded female adapters compatible with pre-insulated pipe and water tank inlet/outlet connections. 25/32 mm, pre-insulated brass-threaded male adapters compatible with pre-insulated pipe and water tank inlet/outlet connections. 25/32 mm, pre-insulated plain ball valve compatible with pre-insulated pipe and water tank inlet/outlet connections. 25/32 mm, high-density field joint kits (inclusive of polyurethane liquid foaming agents a & b, outer hdpe split sleeves, and heavy-duty mastic sealant tape)., industrial-grade semiconductive self-regulating heat tape (35w/meter output at 220v ac, tinned copper metallic braid grounding shield, fluoropolymer outer chemical/frost jacket). spacing 3 mtr, microprocessor-based digital temperature differential controller (auto & manual operation) hosted in an ip65 weatherproof rugged outdoor wall-mount housing., high-precision platinum resistance temperature sensors (dual pt100 type) with a 10-meter factory-shielded signal transmission cable., heavy-duty, industrial m20 3-pin waterproof electrical connection plugs and specialized moisture-proof heat-shrink end seal termination kits., 3-core, 1.5 sq. mm pvc insulated and sheathed flexible round copper power cable, 1100v grade conforming strictly to is 694 year 2010, heavy-duty power distribution panel containing type-c/d curve miniature circuit breakers (mcbs), earth leakage circuit breakers (elcb/rccb), and coordinated type 1 + type 2 surge protection devices (spds) per iec 61643-11., maintenance-free chemical gel earthing system (copper-bonded steel electrode, 3m length, 17.2mm diameter) including eco-friendly low-resistance soil enhancement material (semr) for permafrost soil conditions., early streamer emission (ese) or conventional faraday-rod lightning arrestor system conforming to iec 62305 / nf c 17-102, including 25x3 mm insulated copper down-conductor strips., supervising the installation of system, testing, commissioning & training the staff to operate the system