MAINTENANCE OF VARIOUS TYPE OF EARTHING AND LIGHTENING ARRESTER AT VARIOUS LOCATIONS UNDER GE (AF) MARATHAHALLI, BANGALORE

Amount

Taking down broken earth pit chamber and provision of inspectioin chamber by using precast RCC slab of external dimension 450 x 450 x 75 mm with internal opening 300 x 300 RCC 1:2:3 type B1 20mm graded aggregate reinforced with 8mm CTD bars at 10 Cms centre to centre both ways including finishing and pre cast RCC chamber in 1:2:4 Type B1 of internal dimensions of 300 x 300 x 300mm height with 75mm thick wall and precast RCC 1:2:4 type B1 cover 50mm thick reinforced with 8mm CTD bars at 10Cms centre to centre including one lifting handle including PCC Sub base 1:4:8 100mm thick all as specified and directed. Note : (i) Necessary excavation and removal are include in the quoted rate (ii) The rate including disconnecting the existing strip/wire from earth electrode and refixing the same with suitable bolts and washer.

Material and labour for earthing complete with Copper earth plate electrode 600 X 600 X 6 mm thick buried directly in ground (earth pit not less than 2.25 m deep below normal ground level) with top edge of the plate not less than 1.5M below normal ground level connected to GI earth lead wire 4.0mm dia by means of nuts, bolts, check nuts and washer of GI steel and connecting to testing point including provision of test point and all as shown in electrical plate No. 3 of SSR Pt I. The work is inclusive of necessary earth work and PCC chamber in type CI (1:2:4) with 8 CTD bar reinforcement both ways at 140 mm centre to centre complete all as directed . Notes:- (i) copper strip beyond 7.5 M shall be measured and paid separately (ii) Ther rate include measuring earth resistance.

Material and labour for earthing complete with Copper earth plate electrode 600 X 600 X 3.15 mm thick buried directly in ground (earth pit not less than 2.25 m deep below normal ground level) with top edge of the plate not less than 1.5M below normal ground level connected to copper earth strip 20 x 3 mm thick by means of with brazing at joints and connecting to testing point including provision of test point, test point terminal block made of gun metal or phosphorus bronze size 75x75x25mm and all as shown in electrical plate No. 3 of SSR Pt I. The work is inclusive of necessary earth work and PCC chamber in type CI (1:2:4) with 8 CTD bar reinforcement both ways at 140 mm centre to centre complete all as directed . Notes:- (i) copper strip beyond 7.5 M shall be measured and paid separately under relevant items of this schedule.

Supply and lay connect GI earth strip of size 25 x mm in ground not exceeding 40cm deep/fixing to wall/structure including earthwork and necessarty insulators, clamps, bolts nuts etc.

Supply and fix PVC insulated cable of size 50 Sqmm, 1100 Volts grade with multistrand copper conductors all as specified and directed.

Taking down rusted GI wire and supply and fix GI earth wire 4.00 mm dia for interconnecting of earth elecyrodes all as specified.

Taking down damaged copper earth strip, Supply and fix copper earth of size 20 x 3.15mm with saddles sand fixing screws etc for roof conductors and down conductors above ground level all as specified.

Taking down rusted tubing, supply and lay in ground GI tubing light grade 40mm dia for protecting earth continuity strip all as specified.

Taking down rusted tubing, supply and lay in ground GI tubing light grade 25mm dia for protecting earth continuity strip all as specified.

Taking down perished High Density Polyethylene (HDPE) pipe, suplly and lay the 20mm dia etc complete

Taking down perished High Density Polyethylene (HDPE) pipe, suplly and lay the 50mm dia etc complete

Cutting existing hard standing/flooring not exceeding 600mm width x 600mm depth all as specified as directed.

Material and Labour for Plain Cement Concrete (1:2:4), type B1 (using 20mm graded stone aggregate) as in Coping, bands benching etc including finishing the concrete surfaces even and smooth without using extra cement including necessary form work Complete all as specified and directed by Engr-in-Charge.

Taking down perished / dishaped, horizontal / vertical aluminium conductor of any size and Material and labour for Aluminium strip 25 3 mm size fixed to wall with insulator to over head tank/ Storage shed or any other indicated situation all as specified and directed by Engr-in-Charge. Note : The rate included Scaffloding/ Cradles etc, necessary for execution of work and protective measures.

Material and Labour for Air termination, single pointed, aluminium rod 12mm dia and 300mm long in repairs all as specified.

Material and Labour for Test point terminal block made of gun metal or phosphourus bronze size 75 x 75 x 25mm drilled and screwed including 3 Nos 8mm dia 25 mm long hex, head screw in repairs all as specified

Material and Labour for Maintenance free earthing system consists of One pit using copper - bonded steel rods, Earth enhanching compound and exthermic welding for earth pit electrode and copper bus bar, Each earth pit consists of 17.2 mm copper bonded steel cored electrodes 10 feet ong - 01 No, enhancing Compound 10 Kg bag-3 Nos, inspection chamber installation of the Earthing system with single earth pit digging the earth pit with depth 8 feet interconnecting the copper bus bar with exothermic powder complete all as specified and directed by Engr-in-Charge. Note : (i) Earth resitance value shall be 1.0 Ohms (ii) 25mm x 5mm x 300mm copper bus bar - 01 No (iii) 25mm x 25mm x 150mm bus bar - 01 No (iv) Earth conductor beyond 7.5 Mtr shall be measured and paid separately

Material and Labour for maintenance free ring earth consisting of four earth pits spacing of miniumum 4 mts and using copper - bonded steel rods, compression couplers earth enahching compound and exothermic welding for interconnecting the four earth pit elecytrodes. Each earth pit consists of 17.2 mm copper bonded steel coredelectrodes 10 feets long - 04 Nos, Earth enhancing compound of 10 Kg bag - 16 Nos, 25mm x 2mm copper strip - 16mts, including inspection chamber of size 30cm x 30cm complete all as specified and directed by Engr-in-Charge. Note : (i) Earth resitance value shall be 0.50 Ohms (ii) 25mm x 5mm x 300mm copper bus bar - 01 No (iii) 25mm x 25mm x 150mm bus bar - 01 No (iv) Earth conductor beyond 7.5 Mtr shall be measured and paid separately

Material and Labour for carry out earth resistance tests with the help of earth resistance tester digial/analong and write the derived reading on the Earth Identification plate all as derected.

Disconnecting the connection from the Energy meter terminal, taking down u/s digital meter from the position, replace the defective spares, callibration and re-fixing the same in the position and duly terminate the seal all as specified and directed.

Display board (Earth pit marker) made out of 25mm angular frame with 45 cm height one side welded with 2mm thick MS sheet, frame work of size 15cm x 15cm including excavation, PCC foundation and duly painted with redoxide & two coats black enamel paint with follwing litter display with white paint including taking down detoraited earth pit marker:- (a) Earthing pit No: (b) Earthing resistance: (c) E-N Volt: (d) Check done on: (e) Check due on:

Excavating in trenches n.exc 1.5m Wide and n.exc 1.5m depth for foundation etc for shafts, wells, manholes, columns, pier holes etc 10 Sqm on plan and n.exc 1.5 m in depth and getting out in hard / dense soils all as specified and directed.

Returning, filling in including spreading, levelling watering and well ramming in layers not exceeding 25cm thick in hard / dense soil complete all as directed by Engr-in-charge.

Removing excavated soil to a distance n.exc 50m and and depositing where directed at level not exceeding 1.50m above the starting point complete all as directed by Engr-in-charge.

M.G. Enterprises