Repair/ Renewal of Earthing Infrastructures lightning arrester and connected works at AFA Hyderabad

Amount

M&L for maintenance free chemical earthing with 01 No of copper cladded 17.2mm dia nickel cadmium steel with high tensile strength electrode of each of 3.0 m with suitable compressive coupler planted at depth not less that 3.0 m depth and duly covered with low resistant superior conductive powdered non corrosive, concrete brand earth enhancing material all as directed including connecting up to the common bus bar for a length upto 7.5 m with copper strip of size 25 x 4mm to achieve an earth resistance of below 1.0 Ohms including suitable PCC earth chamber. The copper strip shall be jointed to electrode with exothermic welding and all other joints shall be properly brazed after dismantling the existing unserviceable earthing complete all as specified and as directed.

M&L for maintenance free chemical earthing with 03 No of copper cladded 17.2mm dia nickel cadmium steel with high tensile strength electrode of each of 3.0 m with suitable compressive coupler planted at depth not less that 3.0 m depth and duly covered with low resistant superior conductive powdered non corrosive, concrete brand earth enhancing material all as directed including connecting up to the common bus bar for a length upto 7.5 m with copper strip of size 25 x 4mm to achieve an earth resistance of below 1.0 Ohms including suitable PCC earth chamber. The copper strip shall be jointed to electrode with exothermic welding and all other joints shall be properly brazed after dismantling the existing unserviceable earthing complete all as specified and as directed.

Note for Item No. 01& 02:-

(i) Electrode and copper strip of size 25 x 4 mm shall be welded using exothermic welding for interconnecting the earth electrodes and from earth to grid point up to7.5 m along with 40 mm dia GI light grade protection pipe.

(ii) The carbon based compound shall have a resistance value of less than 1.0 ohm. The compound shall be of minimum 30 kg per pit.

(iii) The bore hole for earth electrode shall not be less than 100 mm dia and 2mtr deep from GL and the extended rod shall be driven to a total depth of 3 mtr.

(iv) Provn of earth pit chamber of internal size 150 x 150 x 150 mm depth with PCC 1:3:6 cover slab 40 mm thick with reinforcement of 8mm TMT bars @ 100mm c/c both direction for each Earthing all as directed by Engineer-in-charge.

(v) Necessary earth work excavation in any type of soil, returning filling and making good the surrounding area complete.

(vi) All the joints Except test point shall be welded/ brazed properly and the copper earth strip whenever laid on the wall, floor etc shall be fixed on ceramic insulators not more than 600mm apart.

(vii) The contractor shall have to give guarantee for maintaining earth resistance of less than one ohm for a period of 05 years certified date of completion and to deposit security deposit of Rs 2000/- per each grid for a period of five years.

Note for Item No. 01:- (i) One No earthing shall be connected for obtaining lowest earth resistance which shall be less than two ohm.

Note for Item No. 02:- (i) Three Nos earthing shall be made for each grid and it shall be connected together for obtaining lowest earth resistance which shall be less than one ohm.

M&L for earthing complete with Galvanised steel earth plate eletrode 600 mm x 600 mm x 6 mm thick burried directly in ground (earth pit not less than 2.25 mtr deep below GL) with top edge of earth plate not less than 1.5 Mtr below normal ground level, earth plate surrounded from all sides by 15cm thick packed layer of charcoal dust and common salt filled in alternate layers and electrode connections by using Galvanised earth strip 32x6mm connected by means of bolts, nuts, check nuts and washer of galvanised iron or steel, provision of 40 mm dia GI pipe medium grade for protection of GI earth strip and 20mm dia GI pipe medium grade for watering arrangement and PCC (1:3:6) type C1 chamber of size 45cm X 45cm X 45cm including, MS funnel, wire mesh, 50 mm thick RCC 1:2:4 type B1 earth pit cover with 6 Nos, 8 mm dia high strength deformed steel TMT bars on both ways including necessary excavation in any type of soil, returning, filling in, removal of surplus soil to distance n exc 50 mtr, provision of charcoal and salt complete all as shown in electrical plate No 3 of schedule Part-I complete all as specified and as directed.

Note:- (i) Cost of GI earth strip and GI protection pipe upto 7.5mtr length shall be deemed to be included in the rate quoted for this item.

(ii) The unit rate shall also includes for Wire mesh, funnel, excavation, returning filling , removing , PCC chamber pit, RCC cover, test point etc.

M&L for earthing complete with Galvanised steel earth plate eletrode 600 mm x 600 mm x 6 mm thick burried directly in ground (earth pit not less than 2.25 mtr deep below GL) with top edge of earth plate not less than 1.5 Mtr below normal ground level, earth plate surrounded from all sides by 15cm thick packed layer of charcoal dust and common salt filled in alternate layers and electrode connections by using Galvanised earth strip 25x4mm connected by means of bolts, nuts, check nuts and washer of galvanised iron or steel, provision of 40 mm dia GI pipe medium grade for protection of GI earth strip and 20mm dia GI pipe medium grade for watering arrangement and PCC (1:3:6) type C1 chamber, MS funnel, wire mesh, 50 mm thick RCC 1:2:4 type B1 earth pit cover with 6 Nos, 8 mm dia high strength deformed steel TMT bars on both ways including necessary excavation in any type of soil, returning, filling in, removal of surplus soil to distance n exc 50 mtr, provision of charcoal and salt complete all as shown in electrical plate No 3 of schedule Part-I complete all as specified and as directed.

Note:- (i) Cost of GI earth strip and GI protection pipe upto 7.5mtr length shall be deemed to be included in the rate quoted for this item.

(ii) The unit rate shall also includes for Wire mesh, funnel, excavation, returning filling , removing , PCC chamber pit, RCC cover, test point etc.

M&L for earthing complete with copper earth plate eletrode 600 mm x 600 mm x 3 mm thick burried directly in ground (earth pit not less than 2.25 mtr deep below GL) with top edge of earth plate not less than 1.5 Mtr below normal ground level, earth plate surrounded from all sides by 15 cm thick packed layer of charcoal dust and common salt filled in alternate layers and electrode connections by using copper earth strip of size 20x3mm connected by means of bolts, nuts, check nuts and washer of copper, provision of 40mm dia GI pipe medium grade for protection of copper earth strip and 20mm dia GI pipe medium grade for watering arrangement and PCC (1:3:6) type C1 chamber of size 45cm X 45cm X 45cm including, MS funnel, wire mesh, 50 mm thick RCC 1:2:4 type B1 earth pit cover with 6 Nos, 8 mm dia high strength deformed steel TMT bars on both ways including necessary excavation in any type of soil, returning, filling in, removal of surplus soil to distance n exc 50 mtr, provision of charcoal and salt complete all as shown in electrical plate No 3 of schedule Part-I complete all as specified and as directed.

Note:- (i) Cost of copper earth strip and GI protection pipe upto 7.5mtr length shall be deemed to be included in the rate quoted for this item.

(ii) The unit rate shall also includes for Wire mesh, funnel, excavation, returning filling , removing , PCC chamber pit, RCC cover, test point etc.

S & F in repair Alluminium strip 25 x 3 mm with DMC / FRP insulators & fixing screws etc. for roof conductors / down conductors / connecting to earth pit to equipement including removing the old unserviceable strip and brazing all the joints complete all as specified and as directed.

S & F in repair Copper strip 20 x 3 mm along with DMC / FRP insulators & fixing screws etc. for roof conductors / down conductors / connecting to earth pit to equipement including removing the old unserviceable strip and brazing all the joints complete all as specified and as directed.

S&F in repairs Copper strip 32 x 6 mm with DMC / FRP insulators fixing screws etc. for roof conductors / down conductors / connecting to earth pit to equipement including removing the old unserviceable strip and brazing all the joints complete all as specified and as directed.

S&F in repairs GI strip 32 x 6 mm with DMC / FRP insulators fixing screws etc. for roof conductors / down conductors / connecting to earth pit to equipement including removing the old unserviceable strip and brazing all the joints complete all as specified and as directed.

S&F in repairs GI strip 25 x 4 mm with DMC / FRP insulators fixing screws etc. for roof conductors / down conductors / connecting to earth pit to equipement including removing the old unserviceable strip and brazing all the joints complete all as specified and as directed.

S & F in repair GI wire 4 mm with saddles and fixing screws etc. for roof conductors / down conductors / connecting to earth pit to equipement including removing the old unserviceable strip and brazing all the joints complete all as specified and as directed.

S & F in repair of Air Termination, Single pointed, aluminium rod 12 mm dia and 300 mm long complete all as specified and as directed.

S & F in repair of Air Termination, Single pointed, COPPER rod 12 mm dia and 300 mm long complete all as specified and as directed.

S&F in repair grid point made out of 4mm thick copper bus bar 250 mm length duly fixed on porcelain insulators housed in suitable size powder coated MS box and connecting up existing earthing together with newly created earthing to achieve the grid earthings barest minimum ohms complete all as specified and as directed.

S& F in repair Earthing grid indicator made out of 3 mm thick MS sheet of size 300 x 200 duly welded with 500 mm long 25x25x6mm angle iron duly fixed near to the grid point with cement grout including writing earthing details such as earth resistance, connected to etc complete all as specified and as directed.

S & F in repair Test Point Terminal Block made of gun metal or Phosphorus bronze size 75 mm x 75mm x25 mm, drilled and screwed and including 3 Nos 8 mm dia 25 mm long head screws. complete all as specified and as directed.

S & F in repair Bib taps, cast copper alloy with crutch or butterfly handle, screwed down, screwed for iron pipe or for brass ferrule including taking down old one complete all as specified and as directed.

Taking up or down down carefully unserviceable GI tubing 40 mm dia including all acessories complete all as specified and as directed.

M&L for steel tubes, 'medium grade', galvanised, 40mm dia with all fitting laid in trenches / pole for protection earth strip complete all as specified and as directed.

M&L for PCC (1:3:6) type C1 chamber of size 45 cm X 45 cm X 45 cm including, 50 mm thick RCC 1:2:4 type B1 earth pit cover with 6 Nos, 8 mm dia high strength deformed steel TMT bars on both ways including necessary earth work return filling and removal of soil and brick work as required at site complete all as specified and as directed.

Excavation in trenches n.exc 1.50 m wide and not exc 1.5 m depth and getting out in soft / loose soil for foundation, trenches etc complete all as specified and as directed.

Returing, filling in including spreading leveling, watering and well ramming in layers not exc 25 cm in soil for foundation, trenches etc complete all as specified and as directed.

Removing excavated materials (soil) to a distance not exc 50m and depositing where directed at a level not exceeding 1.5m above the starting point.complete all as specified and as directed.

Checking the IR of the building all sub main and DBs by using 500V LT meggar and entering in a new IR test register including obtaining the signature of the user rep and producing to Engineer in charge as one time testing during the contract period complete all as directed. Note:- The IR test shall be carried out as required basis during the period of the contract.

Checking the earth resistance of the existing earthing in the technical area including Messes once in three months and opening an earth resistance test register and recording building wise earth resistance including obtaining signature of user's representative in the register complete all as directed. Note: The earthing shall be tested in presence of user representative once in THREE months. One time testing including entering in the register is considered as one job. First testing shall be carried out within 30 days from the date of commencement of the contract.

Checking the serviceability including loose contact and condition of cable terminations of all the existing MCB DBs in the technical area including Messes once in four months and opening a DB serviceability register and recording building wise including obtaining rep of users signature in the register complete all as directed. Note: The checking shall be carried out in presence of user rep once in four months. One time checking including entering in the register is considered as one job. First testing shall be carried out within 30 days from the date of commencement of the contract.

S&F in repairs DMC / FRP insulators, of suitable size to seperate the earth strips from the walls, duly screwed on the walls including makingholes in the earth strips by drilling and fixing the earth strip rigidly with the insulators with GI bolts, nuts, washers etc complete all as specified and as directed.

Taking up or down down carefully unserviceable GI tubing upto 25mm dia including all acessories complete all as specified and as directed.

M&L for steel tubes, 'light grade',galvanised,with all fitting;laid in trenches or fixed on walls,floors etc of folllowing sizes all as specified and directed :-

(a) 20 mm dia

(b) 15 mm dia

AKSHITA ELECTRICAL

M/s Amit Associates

POWER CONSTRUCTION COMPANY

S J REDDY