Providing Chemical ,GI plate Earthing and Lightning conductor works for Ph IX.2 4G Project of MDY OA

Amount

CHEMICAL EARTHING

Supply, Installation, testing & commissioning of Maintenance free Chemical Earthing with following components complete with excavation, civil works, including Labour Charges etc. as required. (Note:- The work has to be caried out as per RDSO specification NO. RDSO/SPN/197/2014 ) i) Earthing electrode shall be made of high tensile low carbon steel circular rod (UL listed), minimum 17.0mm diameter and minimum 3.0mtrs. long, molecularly bonded with copper on outer surface (minimum bonding thickness is 250 Microns). A hole of 100mm to 125mm dia shall be augered /dug to a depth of about 2.8 meters to place the Earth electrode. ii) Earth enhancement material (Non-bentonite) - 30-35 Kgs. After providing the Earth enhancement material around the electrode, remaining portion of the hole/pit shall be filled with the Back fill soil which is taken out during auguring / digging. iii) Copper strip of 300x25x6 mm, to terminate earth rod - 1 no (To be exothermally welded to earth electrode) iv) Construction of earth pit cover with heavy duty FRP Material/ Poly plastic of suitable size.

Supplying and laying of 35 sqmm multistrand single core PVC insulated copper cable on surface/recess/ in the existing pipe, from Main earth electrode to DC earth busbar i/c terminations with copper lugs etc.,as required (20mtrs / site)

Supplying and laying of 40 mm dia rigid PVC pipe on surface of wall / tray for mechanical protection of 35 sq mm cable, i/c providing clamps, cable ties, bends etc. as required (20mtrs / site)

Supply & Installation of Copper tape (25mmx2mm) OR solid copper round conductor (8mm dia) for interconnecting the main earth electrode and the other earth electrode of the Chemical Earthing System including earth enhancement material around the conductor, back fill soil etc as required. (This item shall be executed only if more than one chemical earth electrode is provided in a site) ( 1.5 mtr / site )

Providing and fixing of the 300mm x 50mm x 3 mm thick Copper bus bar as main earth bus bar on wall surface on suitable insulators having suitable no.of holes for connections complete etc., as required

GI PLATE EARTHING

Providing Earthing with G.I. earth plate of 600 mm X 600 mm X 6 mm thick including accessories at a depth of 3.75m as per Specifications, and providing masonry enclosure with cover plate having locking arrangement and watering pipe of 2.7 metre long etc. with charcoal/ coke and salt as required.

Providing and fixing 25 mm X 5 mm G.I. strip in 40 mm dia G.I. pipe from earth electrode including connection with G.I. nut, bolt, spring, washer excavation and re-filling etc. as required ( 3 mtrs / site)

Providing and fixing 25 mm X 5 mm G.I. strip on surface or in recess for connections etc. as required ( 20 mtrs / site)

Supplying and laying of 25 mm X 5 mm G.I strip at 0.50 metre below ground as strip earth electrode, including connection/ terminating with G.I. nut, bolt, spring, washer etc. as required. (Jointing shall be done by overlapping and with 2 sets of G.I. nut bolt & spring washer spaced at 50mm) (For interconnection of existing earthings) ( 3 mtrs / site)

EARTH RECONDITIONING

EARTH STRIP CONTINUITY CHECK

Improving of earth continuity from existing earth electrode upto to the earth bus/ earth terminations by making good of loose connections/joints including providing missing bolts/nuts,spring washers etc.,as required.

MINOR MODIFICATIONS

Providing minor repair works for existing earth pit by making good of loose connections, cleaning GI strip surface of the terminals with sand paper and providing nuts,bolts,spring washers,water funnel and adding salt water to improve earth resitance value to one Ohm and providing earth manhole cover made of heavy duty FRP material and sign writing etc.,as required.

Providing and fixing of the 300mm x 50mm x 6 mm thick GI bus bar as main earth bus bar on wall surface on suitable insulators having suitable no.of holes for connections complete etc., as required

LIGHTNING CONDUCTOR

Providing and fixing of lightning conductor finial made of 25mm dia 1000 mm long GI pipe ( B-class) having single prong at top of the tower with suitable size GI base plate including holes etc.complete as required.

Providing and fixing G.I. tape 20 mm X 3 mm thick on parapet or surface of wall for lightning conductor complete as required (For horizontal run) (20 mtrs / site)

Providing and fixing 25 mm X 3 mm G.I. strip along the tower/Wall with suitable insulators /clamps fixed at suitable interval etc.,as required (For Vertical Run) (25 mtrs / site)

SRI NARAHARI ELECTRICALS