SPECIAL REPAIR FOR IMPROVEMENT TO LIGHTENING ARRESTORS AT AFNET L-2 AT VARIOUS LOCATION AT AFS AMLA

Amount

Taking down existing conventional lightening arrestor (such as roof/down conductor of GI/Al strip, AT rod) any description from roof of building and removing materials for taking credit and making good to the disturbed surfaces to match the existing complete all as specified and directed.

Dismantling existing GI/chemical earthing (such as conductor of GI/coper strip, earthing plate/pipe) any description from building/ signal equiment and removing materials for taking credit complete all as specified and directed.

Material & labour for plate earthing for complete with galvanised mild steel plate electrode 60 cm x 60 cm x 6 mm thick buried directly in ground vertically (in earth pit not less than 2.25 m below normal ground level) with the top edge of the earth plate at a depth not less than 1.5 m below normal ground level, the earth electrode surrounded by adequate quantity of charcoal dust and salt to a packed thickness of 15 cm on all sides and incl GI strip 32x6 mm bolted (with GI nuts, bolts & check nuts) and riveted to earth plate at one end and connected to metallic bodies of equipments etc at the other end, earth strip encased in and including 40 mm bore GI light grade pipe with all fittings from top of electrode to body of equipment fixed with and including 25 x 4 mm flat iron clamps, bolts, nuts and washer and also including providing watering pipe 20mm bore GI pipe medium grade from bottom of earth pit to top of electrode complete with wire mesh, funnel and earth pit in PCC 1:2:4 type B-0 using 12 mm graded crushed stone aggregate and CI cover 10 mm thick hinged to CI frame complete as shown in Electrical Plate No. 3 of SSR Part-I. complete all as spcified and directed.

Note:- (a) Rates for excavation and earthwork in any type of soil/strata, testing on completion, GI strip 32x6 mm dia and 40 mm dia protection pipe upto 7.5 mtr from earth plate is deemed to be included in rate quoted. (b) On testing after completion if, earth resistance not found less than 2 Ohms the earthling shall be re-done at no extra cost.

Supply and fix air termination single pointed aluminium rod 12mm dia and 300 mm long for fixing on GI pipe medium grade 40mm dia pipe duly making suitable fixing arrangement of one end of air termination rod all as specified and directed.

Material & labour for aluminium strip 25 mm x 3.15 mm as earth continuity conductor or main earthing lead fixed to wall on batten/ porcelain/ epoxy insulators or recess or chases or buried in ground or drawn in conduit/ pipe or fixed to poles or any other indicated situation for loop earthing etc. connected upto test terminal point etc including fixing with saddles and screws for fixing porcelain/epoxy insulators/ conduit/ pipe complete all as specified and directed. Note: Insulators/conduit/pipe shall be measured and paid separately under relevent items here-in-after

Material & labour for maintenance free grounding solution set earthing in replacement of old earthing comprising of high tensile low carbon steel rod of 3 meter length & 17.2 mm dia with 250micron (average) molecularly bonded copper thickness on the outer surface along with earth enhancing back-fill compound strictly be a carbon based conductive concrete type which has a resistivity of less than 0.12 Ohm Mtr. Back-fill compound should be electronically conductive (Like in metals) and should not depend on moisture for conduction, back-fill compound should be environment friendly, should solidify when mixed with water and set like concrete and should not leach / diffuse into the ground, back fill compound shall not be mixed with any soil while pouring in the bore hole. The earth electrode should finally be housed in a heavy duty readymade type PVC chamber with future access cover complete all as specified and directed.

Note :- (i) Rates for excavation and earthwork in any kind of soil/ strata, testing on completion, copper strip 20x3 mm and 40 mm dia light grade GI protection pipe upto 7.5 metres from earth plate is deemed to be included in the rate quoted. (ii) On testing, after completion, if the earth resistance < 5 ohms is not obtained, earthing will be rejuvenated without any extra to the department. (iii) Test certificate from the OEM has to be produced by the contractor for the material used in earthing.

Material & labour for earth continuity conductor or main earthing lead fixed to wall on batten or recess or chases or buried in ground or drawn in conduit/pipe or fixed to poles or any other indicated location for loop earthing etc. with GI strip 32 x 6mm complete all as specified and directed.

Material & labour for copper strip 20 mm x 3.15 mm as earth continuity conductor or main earthing lead fixed to wall on batten/ porcelain/ epoxy insulators or recess or chases or buried in ground or drawn in conduit/ pipe or fixed to poles or any other indicated situation for loop earthing etc. connected upto test terminal point etc including fixing with saddles and screws for fixing porcelain/epoxy insulators/ conduit/ pipe complete all as specified and directed. Note: Insulators/conduit/pipe shall be measured and paid separately under relevent items here-in-after

Supply and fixing test point terminal block made of gun metal or phosphorus bronze size 75x75x25mm drilled and screwed including 3 Nos. 8mm dia 25mm long hexagonal head screws including provision of 30cm x 25cm x 8cm sheet metal box made out of 3.15 m thick CRCA sheet with front hinged door shutter & locking arrangement and duly painted with two coats of synthetic enamelled paint over a coat of red oxide primer complete all as specified and directed.

Supply & fixing PVC junction box IP 65 of size 200 mm x 160 mm x 98 mm having shutter & lifting knob with provision of earthing strip entry glands on wall/poles with suitable size of nut, bolts and washers complete all as specified and directed.

Supply and fixing GI pipe of size 50 mm bore, light grade to be fixed on pole for GI strip protection including socket bend etc complete all specified and directed.

Supply and fixing post insulator epoxy LV type suitable for lightening conductor aluminum strip size 25x4 mm, fixed on wall/roof/pole including screws complete all as specified and directed.

Supply and lay in trenches / fixed to walls PVC super quality pipe not less than 32 mm dia class 3 grade for protection of earth strip complete fixing with suitable clamps at 0.5 mtr span all as specified and as directed. NOTE :- Rates for flat iron clamps, bolts, nuts and washer etc are deemed to be included in rate quoted.

M&L for Cement concrete 1:2:4 type, B-1 (using 20 mm graded stone aggregate) as in bed blocks, copings and the like including weathering, slightly rounded or chamfered angles & throating including provision of necessary formwork, complete all as specified and directed.

Note:- The amount against the Schedule of Credit mentioned in the tender document shall be deducted from the total amount quoted against Sch 'A' while deriving the Contract Sum for Acceptance.

Paragon Electrotechnics (BID ID -3496576)

M/s Vinod Yadav (BID ID -3494074)

Shri Sai Enterprises (BID ID -3497566)