REPAIR AND MAINTENANCE OF LIGHTING PROTECTION AND EARTHING AT AF STN NAL UNDER GE (AF) NAL

Supply & Fix as in repair air termination single pointed copper rod 12mm dia, and 300 mm long complete all as specified and directed by Engineer-in-charge .

Material & labour for copper strip 20 mm x 3 mm with proceline insulator and fixing screws etc for roof conductors and down conductors or 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 through wall /floor / roof or fixed to poles or any other indicated situation for loop earthing etc. as required including taking down existing old unsv strip complete all as specified and directed by Engineer-in -charge . Note:- (i) Excavation & earth work shall be measured and paid for separately. (ii) Cutting holes in the wall and making good with cement plaster / mortar alongwith distemper / white wash is deemed to be included in the rate quoted. (iii) Cost of Insulators required for fixing of strip including nuts and bolts is also included in the unit rate quoted) above the ground all as specified and directed.

Material & labour for GI strip 25 mm x 4 mm with proceline insulator and fixing screws etc for roof conductors and down conductors or 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 through wall /floor / roof or fixed to poles or any other indicated situation for loop earthing etc as required including taking down existing unsv strip complete all as specified and directed by Engineer-in -charge . Note:- (i) Excavation & earth work shall be measured and paid for separately. (ii) Cutting holes in the wall and making good with cement plaster / mortar alongwith distemper / white wash is deemed to be included in the rate quoted. (iii) Cost of Insulators required for fixing of strip including nuts and bolts is also included in the unit rate quoted) above the ground all as specified and directed.

All as per description of serial item No. 3.00 (here in before) but galvanised iron strip of size 32 mm x 6 mm

Material & labour in repair test point terminal block made of gun metal or phosphorus bronze size 75x75x25mm drilled and screwed including 3 Nos. 8mm dia 25mm long hex. head screw complete all as specified and directed by Engineer-in-charge .

S & F in repair epoxy based insulator 40mm height for fixing GI strip/copper strip on wall / ceiling / floor / poles etc complete all as specified and directed by Engineer-in-charge . Note:- This item is considered for replacement of insulators other than those catered for unit rate of serial item No. 2, 3 & 4 here-in-before.

Taking down / out existing serviceable copper / GI strip of any size as roof conductors and down conductors or earth continuity conductor fixed to wall on batten or recess or chases or buried in ground or drawn in conduit/pipe or fixed to poles etc, incl nut bolt etc, straightening the twisted / bent up portion of strip and re-fixing in position complete all as specified and directed directed by Engineer-in-charge . Note:- Welding / soldering of earth continuity conductor where required shall deemed to be included in the unit quoted rate .

Material & labour as in repair for copper earthing with copper earth plate 600 mm x 600 mm x 3.15 mm thick, burried directly in ground in vertical position, earth pit not less than 2.25 Mtr deep below ground level with top edge of the plate not less than 1.5 Mtr below ground level. The earth plate to be connected with copper earthing strip of size 20 mm x 3 mm thick as earth lead by means of brazing between copper strip and earth plate min 45 cm in vertical length and copper strip also to be joined by brazing only. The copper earthing strip to be protected by galvanised iron pipe 40 mm bore (medium grade) up to ground level and there after with 40mm dia HDPE pipe up to test point. Earthing shall include provision of funnel with 20mm bore galvanised iron pipe (light grade), wire mesh, charcoal or coke and common salt in alternate layer of 15cm (compacted thickness) up to 90 cm all around earth plate further filled with 60 cm thick Tibba sand and 2nd layer with 30 cm of Magnesium sulphate powder (compact thickness ), 3rd layer with tibba sand up to ground level. Earthing shall also include concrete earth pit in PCC (1:3:6) type C-1 (with 20mm graded aggregate), 50mm thick precast RCC (1:2:4) cover slab (re-inforced with 8mm dia TMT bar @ 15 cm C/C bothways and suitable handle made of 10mm dia) including necessary earth work in excavation, returning filling and removal of surplus earth upto a distance not exceeding 50 Mtr etc all as shown on electrical plate No. 3 of MES Schedule Part-I complete to obtain less than 2 Ohm earth resistance value, complete all as specified and directed. Note :-Copper earthing strip (20mm X 3mm) up to 7.5 mtr included in this quoted rate.

All as per description of serial item No. 8.00 (here in before) but using galvanised steel earth plate electrode 600 mm X 600 mm X 6 mm thick electrode and galvanised iron strip 32×6mm as earthing lead connected by means of bolts, nuts, check nuts and washers etc and the GI earthing strip to be protected by galvanised iron pipe 40 mm bore (medium grade) up to ground level and there after with 40mm dia HDPE pipe up to test point

All as per description of serial item No. 8.00 (here in before) but using galvanised steel earth plate electrode 600 mm X 600 mm X 6 mm thick electrode and galvanised iron strip 25 mm X 4 mm as earthing lead connected by means of bolts, nuts, check nuts and washers etc and the GI earthing strip to be protected by galvanised iron pipe 40 mm bore (medium grade) up to ground level and there after with 40mm dia HDPE pipe up to test point