IMPROVEMENT TO LIGHTNING ARRESTOR AND EARTHING INFRASTRUCTURE AT CERTAIN LOCATIONS AT DIGARU 2ND CALL

Amount

SCHEDULE 'A' PART-I (B/R PORTION)

Earthing complete with copper earth plate electrode 60 cm x 60 cm x 3.15 mm thick buried directly in ground (earth pit not less than 2.25 meter deep below normal ground level) with top edge of the earth plate not less than 1.5 meter below normal ground level, connected to copper strip of size 20 x 3mm length 7.5m (Minimum)as earthing lead by means of bolt and nut, check nuts and washer of galvanized iron or steel and earth lead protected by 40mm bore light grade GI ppe all as shown in electrical plate No 3 of MES Schedule part I with and including excavation & earth work in any type of soil, providing charcoal dust and common salt upto 15 cm above top edge of earth plate, construction of PCC pit in cement concrete 1:2:4 type B-1 with 50 mm thick RCC cover 1:1.5:3 type B-1 reinforced with 8 mm dia MS deformed bars @ 100mm center to center both ways, watering arrangement with funnel and wire mesh and watering pipe of 20mm bore GI medium grade and 40mm bore light grade pipe for earth lead protection and testing on completion complete all as specified and directed.

Material and labour for chemical earthing complete with copper plate electrode of size 90 cm x 60 cm x 5 mm thick buried directly in ground (earth pit not less than 2.25 meters deep below the normal ground level) with top edge of plate not less than 1.5 m below normal ground level connected to copper earth strip 32 x 6 mm length 7.5m (Minimum) as earthing lead by means of copper bolts, nuts, check nuts and washers all as shown on electrical plate No 3 of SSR Part-I (2009), using adequate quantity of chemical to be provided and connected to earth test point including 25 mm bore GI medium grade pipe for watering with funnel and wire mesh and 65 mm bore GI light grade pipe for protection of earth strip and providing water supply connection from nearest water supply point and testing including PCC chamber complete to achieve earth resistance less than 01.00 ohm all as specified and as directed. Note :- (i) The unit rate shall deemed to include for earth work in soft/loose soil, PCC (1:2:4) type B-1 chamber, RCC (1:1.5:3) cover 50 mm thick reinforced with 8 mm dia TMT bars @ 100 mm c/c both ways, funnel with watering pipe 25 mm bore medium grade, GI protection pipe light grade 65 mm bore and wire mesh complete in addition to item No 1 (a) to (e) of preamble (notes) under sub-heading Earthing, specified on SSR Part-II 2020. (ii) If the desired earth resistance is not achieved during testing as per IS the complete earthing shall be redone by the contractor at his own cost and no extra claim shall be admissible in this regard. (iii) Copper strip shall be provided upto earth test points as directed. (iv) The unit rate shall be inclusive of filling the earth pit with sodium chloride 200 kg (Minimum), Magnesium and copper sulphate 100 kg (Minimum) and balance charcoal in layers upto 15 cm above the top edge of earth plate all as directed.

Supply and fixing of copper air termination rod 16mm dia and 1.20 m long including poviding with all accessories to fixed at the existing position at top of the roof level etc complete all as specified and as directed.

Supply and fixing GI Pipe of 40mm dia "medium grade" suitable for holding Lightening arrestor including fixing accessories such as clamps/Nut Bolts and 4mm dia GI wire to its existing position complete all as specified and as directed.

Supply and fixing earth continuity conductor or main earthing lead made of Copper strip of size 32 x 6 mm as roof conductor/down conductor above ground level/ burried in ground fixed with saddles (made of Porcelain / PVC ) and screwd at a distance 30 cm complete all as specified and as directed.

Supply and fixing Porcelain post insulators of size 25mm long for fixing of aluminium strips/GI strips/ Copper strip for roof conductor and down conductor etc complete all as specified and directed.

Supply and fixing in repair test point terminal block made of gun metal or phsphorus bronze size 75 x 75 x 25 mm drilled and screwed including 3 nos, 8mm dia 25mm long hexagonal head screw including dismantling of the same etc complete all as specified and directed

M/S. SUBHAS CONSTRUCTION CO.

KR POWER INFRA INDIA PVT LTD.

M/S PRASANTA MAHANTA

TOTCO

M/s JK Jangid and Company

OM INFRA

M/S DB TRADING CO