Bharat Sanchar Nigam Limited Tender

Providing and fixing of lightning arrestor of 1500 mm long, 25 mm dia hollow Copper tube having wall thickness not less than 1.60 mm inclusive of 5 spikes of 150 mm length i/c 15 mm length tinning the bottom portion of spike i/c fixing with teflon sheet/ earthing insulator on Top of tower with necessary brass nut/bolts as per specification and drawing attached for all heights of towers GBT and RTT at the scattered sites as per the directions of Engineer in Charge. complete etc as reqd

Supplying, Installation, Testing, & Commissioning of Maintenance free Chemical earth station as per latest RDSO specifications consisting of following:- (a) Steel electrode, High Tensile, low carbon molecularly bonded with copper on outer surface as Per UL requirement of 3 mtrs long, 17 mm dia with copper bonded thickness of minimum 250 microns and a copper coated low carbon steel strip of 300mm x 25mm x 6mm with suitable hole shall be exothermically welded to main Earth electrode for taking main the connection to main earth bus - 1No. (b) Earth Enhance material, Maintenance free, Environmental friendly, Mineral compounds, Semi soluble, non corrosive, conductivity improving material confirming to IS 62561 Part 7 of RDSO approved) = 30-35 Kg c) Poly plastic, Heavy Duty, weather-proof, environmental free earth pit chamber with cover size about top dia 250 mm bottom 330 mm and height 260 mm. Heavy duty of 7 TON load capacity, the base unit should have knockouts for interconnection of strips. Note:- (1) Measurement of earth resistance will be done after 24 hours as per RDSO specification. (2) Chemical Earthing work should be strictly carried out as per RDSO Specification attached), (3) The above work is all inclusive i/c transportation, T&P and testing at site complete as required. (4) This item will be executed only if existing tower earth is not available at site and as per decision of Engineer -in-Charge/competent authority.

Providing and fixing 50x3 mm GI strip along the leg of the tower at suitable interval for connection from lightening arrestor to existing earthing system at ground of tower with necessary screws /clamp at scattered sites of towers as per the directions of Engineer in Charge complete etc as reqd ( This item will be executed only if existing GI Strip is not available at site and as per decision of Engineer -in-Charge/competent authority.)