AUGMENTATION OF EXTERNAL ELECTRIC SUPPLY NETWORK SYSTEM AND REPLACEMENT OF 02/04/06 POLE STRUCTURE TO HT SWITCH GEAR SYSTEM AND ALLIED WORKS AT 23ED AF STN UNDER GE AVADI

Earthwork excavation in trenches not exceeding 1.5 m wide and not exceeding 1.5 m depth and getting out in soft / loose soil for laying cables / pipes / erection of poles etc. complete all as specified and as directed. Note: Excavation shall be carried out manually at certain location at site where directed by the Engineer-in-Charge to avoid breakage of existing Electrical ,water connections. Rate quoted by the contractor shall deemed to be include for the manual excavation. If any damage occurs during excavation to the existing electric cable, water pipe lines etc shall be made good by the contractor without any extra cost to the Government.

Returning filling in soft / loose soil including spreading, levelling, watering and well ramming in layers not exceeding 25 cm thick complete all as specified and as directed.

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

M&L for unreinforced precast concrete cable cover, class HV, type 1, flat, of size 300mmx180mmx40mm covering as a protection to the electric cable laid dry, flat , transversally along the length of cable on sand cushioning complete all as specified and as directed.

Supply and lay GI tubes, 'light grade' galvanised 80mm bore as a protection for cable/ earthing strip with all fittings laid in trenches/walls / under road / drain crossings etc., complete all as specified and directed.

M&L for filling the fine sieved excavated dry soil as in cushioning to underground cable 8cm before laying the cable and 15cm after laying the cable and punned down to 18 cm thick complete all as specified. Note: Thickness shall be measured after punning.

Supply and laying in trenches/poles/wall etc HT UG Cable XLPE insulated with multistranded aluminium conductor armoured with galvanised steel wire / taps 11000 volts grade conforming to IS specifications and of size 3 core 95 sqmm complete all as specified and as directed. Note: (a) The routine tests and acceptance tests as per IS 7098 (Part –II) shall be carried out at factory premises and contractor shall submit the test report alongwith paid vouchers and quoted rates shall deemed to be include for the same.

Supply, installation, testing and commissioning of 11 KV, 630 A, 25 KA/3 Sec 3 way (1LBS+2 VCB) Ring Main Unit motorised operated RMU with PT Chamber, Auxiliary transformer battery & battery charger. 11 KV SF6 Insulated 3 way ( 01 LBS+2 VCB) Ring Main Unit of outdoor type, motorised type, motorized operated, Extensible type with PT Panel 1-Ph PT, 11kv/110V, 25VA, Cl-1, Auxiliary Transformer 11 KV/ Sqr 3/415 Sqr.3, 500 VA with surge suppressor (Rated Voltage 9 KV) Incoming 1 @ 2 is LBS 630 Amps. Triple Pole, Single break, 3- position (ON, OFF and Earth) Ring Main switches, each with motor charges spring mechanism and fully rated earth switch, Air insulated cable boxes for bottom entry of single run of 3 core cable upto 300 Sqmm, FPI for load break switches CTs for metering of ration 400-200/1A, 2.5 VA, CL0.5, Outgoing VCB consist of 11 KV, 21KA/3 Sec, 630 Amps triple pole and vacuum circuit breaker with independent manual charged spring mechanism and fully rated earth switch with provision for earth of the cable. Earthing of the outgoing cable is achieved by the use of CB in series with the off- load dis-connector/ selector switch. This enhances the making capacity of the earth switch, Each outgoing feeder with Air insulated cable boxes for bottom entry of single run of 3 core cable upto to 300 sqmm over current & earth fault relay with digital display & self Powered CT's for metering & protection circuit mounted on cable box of rating 100-50/1-1A, Cl 0.5, 2.5VA, 5P10. Capacitive voltage indicators - LED Display, Tripling coil for tripping the circuit breaker in fault condition, Local PUSH to TRIP mechanism for emergency trup. Right Angle boots ( Non touch Proof type) MFM. The combined unit shall consist of 630 Amps continuously rate copper bus bar, positive standard mechanical interlocks to avoid unsafe operation, Mimic diagram in front Panel complete with status indicators (On- Off-Earth) . Provision for deadlocking for open, close, earth position in correct sequence, Manometer for indicating SF6 gas pressure with green & red zone, hooks strong enough to take the load of entire unit while lifting by means of crane, SF6 tank of 3mm stainless steel, robotically welded construction ( degree of protection IP-67), External stud for earthing connections, outer enclosure (cladding) constructed with 2mm CRCA sheets (having degree of protection IP54) , Terminal Protector Boots for each function. The unit shall be painted in RAL7035 Paint shade complete all as specified and as directed. (Location:- AF main Gate-01 Nos, Narender Auditorium- 01, DC-III- 01)

M&L for cutting the existing road/path of any description for laying of GI tubing and making the good to disturbed road/ path with and including provision of plain cement concrete 1:2:4 type B1 using 20mm graded stone aggregate complete all as specified and directed.

M&L for drilling/ making bore hole under the road in any type of soil through trenchless technology by HDD (horizontal direction drilling method) including necessary machinery as required, preparing and setting up the plant and equipment , preparing new pipe/cable laying work like excavation shoring/ strutting etc drilling, stringing reaming pulling back the new work on the path alignment proper disposal of drilling fluid and the ground penetrating radar survey to protect existing utilities at the pipe/cable installation location restoration of site after completion all inclusive as per and STT IS No 2.3 2.2 2.2 second edition 2008 code of practice of trenchless technology suiting Indian condition for making horizontal bore size of 75mm dia suitable for HDPE pipe insertion under the road crossing hard standing including provision of HDPE pipe of size 75 mm nominal dia of grade PE 80 for protection of cable to any depth complete all as specified and directed.