PROVN OF HT ELECTRIC RING MAIN UNIT FOR EXTERNAL ELECTRIC SUPPLY AT NIWARU MIL STN

Amount

Excavation in trenches not exceeding 1.5 metre wide and not exceeding 1.5 metre in depth for foundation etc or for shafts, wells, cess pits, manholes, pier holes, laying cables erection of poles / struts/stays etc not exceeding 10 Sqm on plan, not exceeding 1.5 metre in depth and getting out in any type of soil complete all as specified and directed.

Returning, filling in, including spreading, levelling, watering and well ramming in layers not exceeding 25cm in any type of soil complete all as specified and directed.

Removing of excavated material (soil) to a distance not exceeding 50 metre and depositing where directed at a level not exceeding 1.50metre above the starting point complete all as specified and directed

M&L for sand cushioning to PVC underground cable with screened and washed sand and punning to provide a required cover complete all as specified and directed.

Supplying and laying factory made un-reinforced PCC precast cable covers class HV, type I, with peak, size 300mm x 180mm x 40mm complete all as specified and directed.

Supply, laying and commissioning XLPE insulated screened, PVC bedded galvanised steel strip or wire armoured electric power cables (heavy duty) cross sectional area 95 Sqmm, 3 core with aluminium conductor 11000 volts grade IS-7098 marked, suitable for HT 11 KV (E) System laid in trenches/ ducts/ encased in GI pipe/ fixed to poles including jointing & testing complete all as specified and directed.

Supply & fixing or laying galvanised steel tubing light grade (ISI marked) 100mm bore for protection of underground cable on poles / walls under road crossing etc complete all as specified & directed.

M&L for cable end termination, jointing kit for HT 11 KV (Earthed) grade cable for cold shrinkable type joint complete with jointing material and accessories suitable for 3 core XLPE armoured aluminium conductor complete all as specified and directed of following sizes :-

(a) 95 sqmm x 3 core outdoor type end termination

(b) 240 sqmm x 3 core indoor type end termination

(b) 95 sqmm x 3 core indoor type end termination

M&L for jointing kit for HT 11 KV (Earthed) grade cable for straight through cold shrinkable type joint complete with jointing material and accessories suitable for 3 core XLPE armoured aluminium conductor complete all as specified and directed of following sizes :-

(a) 50 sqmm to 95 sqmm x 3 core

(b) 240 sqmm to 300 sqmm x 3 core

M&L earthing complete as per electrical plate No 3 of MES SSR Part-I with galvanised steel earth plate electrode 600 mmx600mmx6mm, buried directly vertically in ground in a pit depth not less than 2.25 metres below ground level with top edge of earth plate at a depth not less than 1.5 metre below normal ground level connected to and including galvanised iron or steel earth strip 32mm x 6mm by means of bolts, nuts check nuts and washers of galvanised iron or steel. Earthing strip shall be protected by galvanised iron or steel pipe 40 mm bore light grade and connected to continuous earth wire on pole / test point. Watering pipe shall be 20 mm bore GI medium grade. The earthing shall be of inclusive of excavation & earth work in any type of soil, charcoal, salt, funnel PCC pit and RCC cover complete all as specified & tested complete. NOTE:- (i)The concrete pit shall be made in PCC 1:3:6 type C-1, using 12.5mm graded crushed stone aggregate 40mm thick precast cover slab of RCC (1:2:4), type B-1, using 20mm graded crushed stone aggregate with suitable MS handle in lieu of CI cover shown in electrical plate No 3 of MES SSR Part-I shall be provided. Reinforcement in RCC cover shall be of 8mm dia TMT bars laid @150mm c/c both ways (ii) Quoted shall include the cost of 7.5 metre GI pipe for protection of earth wire/strip. (iii) Quoted shall include cost of 7.5 metre earth lead wire/strip. (iv) Earth electrode shall be surrounded by adequate quantity of charcoal dust and salt to a packed thickness of 15 cm on all sides.

Supply, installation, testing and commissioning of 3 way, 11KV Outdoor (IP54) type Extensible Ring Main unit (RMU) fully motorized consist of 2 Nos vacuum breakers for incoming and 1 No vacuum breaker for outgoing with self-powered relay for protection of transformer, floor mounted, fully motorised with internal copper bus bars and all parts such as bus bars, LBSs connections of RMU should be enclosed in stainless steel tank. RMU shall be solid earthing system and complete with all accessories such as Terminal boots, VPIS, FPI, cable supports, mechanical indications for Load break switch ON/OFF, Spring charge, Manometer as per with IEC standards 62271-200. Internal arc type tested for 21kA for 1 sec. and also RMU test reports shall be type tested with min. 3 functional units and the type test reports on single functional unit shall not be acceptable and including necessary interlocking paver block M-30 and 60mm thick alongwith PCC and sand as site requirement for safety and operation etc, complete all as specified and directed.

Rated voltage should be – 12 KV

Rated power frequency voltage – 28 KV

Rated lightning impulse withstand voltage – 75 KV

Rated current for LBB feeder – 630 Amps

Rated short time current withstand – 25 KA for 1 Sec

Rated short time making current – 50 KA

Ambient Temperature – (-5 deg C to +40 deg C)

Rated internal arc rating – 21 KA for 1 Sec for tank and cable box both category IAC-AFLR.

RMU shall be fully motorized and manual operation both.

RMU shall be provided with battery and battery charger rated for 24V DC for motorization suitable for 10 Nos on/off operations.

RMU shall be extensible by means of plug in type arrangement in future.

RMU manufacturer shall use own make of vacuum interrupter, relays etc.

RMU tanks shall be 2 +/-0.5 mm thick of stainless steel material welded by using robotic welding or manual tight welding. Sealed for light high having IP 67 degree protection with S&F gas as insulation with leakage rate less than 0.1% per year tested as per IEC 62271-200.

RMU enclosure shall be made up of CRCA having minimum thickness of 3.15 mm

RMU cable box shall be only front accessible type to have easy access to protection and metering CTs.

RMU shall be painted with suitable painting having thickness 60-80 micron.

RMU shall have metering bus connected metering compartment shall be preferably on the left side.

RMU metering compartment shall be provided with potential transformer rated for 11 KV/3/110KV/3, 25VA for metering purpose having class – 0.5accuracy.

RMU shall be provided with metering CTs rated for 200-100/1 amps class-0.5 accuracy, 2.5 VA burden for circuit breakers.

RMU shall be provided with metering CTs rated for 200-100/1 amps class-10P10 accuracy, 2.5 VA burden for circuit breakers.

All feeders of RMU shall be provided with multifunction meters having complete range of measurement including maximum demand and shall have serial port for communication on MODBUS protocol. The RMU manufacturer shall user meters of own make.

All circuit breaker feeders shall be self powered and shall be provided with over current & earth fault protection for transformer and shall have serial port for communication on modbus protocol.

RMU shall be provided with fault passage indicators on every isolator having LCD display and auto reset facility and one NO/NC auxiliary contact for showing status of SCADA.

Nominal operating gas pressure -- 1.2 Bar abs

RMU shall have Live Cable LED indication through capacitor voltage divide mounted on the bushings.

Note: The quoted rates include PCC footings with brick masonry 1.2 M wide on all four sides including making arrangements for cable entry on rear side of RMU duly plastered including approach stairs. RMU shall be installed at a height of 75 cm above ground level.

Labour only for boring under road/drain/PCC path By mechanical manual method for inserting the 100 mm dia light grade pipe GI tubing for cable protection all as specified and directed.

RAJENDER ENTERPRISES

LAKSHMI ASSOCIATES

SHREE BHAGWATI ENTERPRISES

S.G.ENGINEERING COMPANY