Special Repair Replacement of Two Pole Structure to 4 Way RMU at HQ AFC, Port Blair

Amount

Dismantling and taking out old existing Two Pole Structure after necessary electrical disconnection & removing fixtures complete all as specified and as directed.

M & L for Cable End Termination Joint, Heat Shrinkable type, Indoor type, suitable for 11000 Volts, 3 Core, 185 Sq.mm, HT, XLPE Insulated, Armoured Power Cable with Aluminium Conductor and testing after jointing complete all as specified and as directed.

M & L for Straight Through Joint, Heat Shrinkable type, Outdoor Type, suitable for 11000 Volts Grade, 3 Core, 185 Sq.mm, HT, XLPE Insulated, Armoured Power Cable Aluminium Conductor and testing after jointing complete all as specified and as directed.

Supplying, laying and testing HT UG Cable, XLPE insulated, screened insulated, steel strip armoured and pressure extruded PVC bedded, 11000 Volts grade [heavy duty] suitable for Earthed System with aluminium conductor of size 3 Core, 185 Sq.mm conforming to IS – 7098 [Part – II] laid in trenches, fixed to walls or passing through pipes and connecting up complete all as specified and as directed.

Supply, Installation, Testing and Commissioning of fixed type, floor mounted, 12 kV, 630 Amp, Outdoor type[IP-54] with welded stainless steel tank with degree of protection IP67 one side extendable, copper bus bar/manual compact switchgear[Ring Main Unit] 4-way four modules CVVV type comprising of 01 No 12kV, 630 Amp, SF6 Insulated load break switch as incomer and 03 Nos 12 kV 630 Amps SF6 insulated outgoing Vacuum Circuit Breaker[VCB] suitable for installation in 12kV 3 phase, 3 wire 50 cycle effectively earthed system including electrical and manual spring charging mechanism and fully rated earth switch with provision for earth and testing of cable including Air insulated cable boxes with gland plate suitable for bottom entry 3 Core XLPE, 11kV underground cable up to 300sqmm with provision for earthing of cable including set of hooks strong enough to take the load of entire unit while lifting by means of crane, LBS shall have self powered short circuit earth fault indicator [Fault Passage Indicator] and the VCBs shall have self powered numerical protection relay for short circuit over current and earth fault, low energy release series trip coil for VCB tripping circuit, low voltage ring type. CT : 50A/1A Class 5p10, 2.5 VA for each phase shunt trip circuit for external trip signal all as specified and as directed. Note : 1. Each RMU shall consist of its own power supply unit incl. auxiliary power transformer, batteries & Battery Charger to provide stable power source for the RMU. 2. Foundation work as per OEM's Recommendation is deemed to be included in the quoted rates for installation of RMU.

Note for Serial Item No. 4: RMU shall be 11 KV, 630 Amps, 21 kA for 3 Seconds, SF6 Insulated, Manual / Motorised, Outdoor, Extensible type with Air Insulated Bus Connected Metering unit, Type tested in line with latest IEC Standards, suitable for operations near coastal area and at 40ºC Ambient Temperature without any de-rating, Switchgear and Busbar shall all be contained in a Stainless Steel Enclosure [Minimum 2mm thick AISI 441 Grade] filled with SF6 at 0.3 Bar [300 hPa] Relative Pressure, RMU Tank shall provide Full Insulation and Switchgear shall be insensitive to the environment with Degree of Protection of IP67, Switchgear Operating Mechanism shall have an IP2X Protection and Cable Chamber shall have IP3X Protection, Outer Enclosure shall be IP 54 type tested, Powder Coated with Pure Polyester Based Paint, suitable for the site installation conditions, Accidental Overpressure due to an Internal Arc is limited by the opening of the safety valve, at the bottom of the metal enclosure, away from the operator, Plug in type of extensibility must be provided and coupling busbar should not be exposed to air to avoid oxidation of busbars. Extension of cubicle shall require 450mm to handle and the gap between the coupled RMU’s must be within 10mm.

Each Load Break Switches shall comprise of 1 Nos of 11 kV, 630 Amps, 21 kA / 3 Seconds, 3 Pole, Manual, Load Break Switch, Short Time Current [STC] 21 KA for 3 Sec, Rated Power Frequency Withstand Voltage of 28 KV, Rated Lightning Impulse Withstand Voltage 75 KVp, Fault Passage Indicator System [FPIS] & Voltage Presence Indicator System [VPIS], Self Powered Numerical Protection Relay for Short Circuit, Over Current and Earth Fault, Low Energy Release Series Trip Coil for VCB Tripping Circuit, Low Voltage Ring type CT : 50-50/1A, Class 5P10, 2.5VA for each Phase, Shunt Trip Circuit for External Trip Signal, all Mechanical Interlocks etc. as per IEC 62271-100/102/200 and 1 Nos of Fault Passage Indicator [FPI] with Current Sensors [CBCT] for Earth Fault.

Notes: [a] An operator situated in front, lateral and rear [A-FLR 21kA – 1 Sec, Downwards Exhaust, for Tank as well as Cable Compartment] of the RMU Switchboard during an internal fault shall not be exposed to the effects of Arcing. Internal Arc Type Test Report for IAC AFLR 21 kA for 1 Sec for both Tank & Cable Box shall be for minimum 3 Way / 3 Function RMU. [b] All operations shall be from front of the RMU, including access to cable bushings. Bushings along the sides or the rear of the RMU are not acceptable. [c] The rate quoted is also deemed to be including the cost of connection of HT Cables up to 3 Core, 120 Sq.mm from 2 Pole / 4 Pole Structures, removing of cable loop and reconnection to RMU complete all as specified and as directed. [d] End termination joints shall be measured and paid separately. [e] CONSTRUCTION OF PLINTH / FOUNDATION FOR 11 kV RMU: The rate quoted is deemed to be including the cost of Plinth / Foundation and nothing shall be paid extra on this account. The foundation shall consists of Two Parallel Block Masonry Walls built in Cement Mortar 1:6 of length 2.10m, suitable thickness and height as per the manufacturer’s instructions over PCC Concrete Bed of 150mm thick in PCC 1:4:8, Type D-2, using 40mm graded stone aggregate over 150mm thick Hardcore of gauge not exceeding 63mm of broken stones or boulders, deposited, spread and levelled in layers not exceeding 15 cm thick watered and rolled, over 150mm thick Sand Bed, rendering to brick surfaces, 15 mm thick in Cement Mortar 1:4, and finishing the top surface even and smooth without using extra cement, applying Three coats of white washing including earthwork excavation complete all as per manufacturer’s recommendations, drawings, as specified and as directed.

Excavation in trenches not exceeding 1.5m wide and not exceeding 1.5m deep in Soft / Loose soil complete all as specified and as directed.

Returning, filling in, including spreading, levelling, watering and well ramming in layers not exceeding 25cm thick of excavated soil complete all as specified and as directed. Note: A deduction of 10% shall be made from total computed volume of filling to cater in bulk irrespective of machinery used for ramming.

Removal of excavated material [Soil] to a distance not exceeding 50m and depositing where directed at a level not exceeding 1.5 m complete all as specified and as directed.

Supply and laying of DWC [Double Wall Corrugated] HDPE Pipe and including fittings such as couplers, bends, end caps etc., ISI marked of Outer dia of 110mm and Inner dia 95mm polyethylene with smooth internal and profiled external surface for non pressure under ground cable complete all as specified.

M & L for Earthing complete with Galvanised Steel Earth Plate Electrode 600 X 600 X 6 mm thick burried directly in ground [earth pit not less than 2.25 m deep below ground level] with top edge of Plate not less than 1.50 m below normal ground level connected to 32 X 6mm GI Strip [Earth Lead] and GI pipe 50 mm, Medium Grade for earthing lead protection to the extent of maximum 7.5m, Earth Plate Electrode surrounded by 150mm thick packed layers of Charcoal and Common Salt filled in alternate layers, connected to the Plate by means of GI Bolts & Nuts complete all as per Electrical Plate No. 3 of SSR Part – I, connected to panel / DB including testing on completion including main earthing, Charcoal, Common Salt, PCC [1:2:4, Type B1] Pit with RCC 1:2:4, Type B1 Cover, 50 mm thick with 6 Nos, 8 mm dia TMT bars in both ways, MS frame made with 40 X 40 X 6 mm Angle Iron, MS Funnel with 20 mm bore, medium grade GI Watering pipe, wire mesh, earth work excavation, return filling, removal of surplus soil etc. complete all as specified and as directed.

S & F Earth continuity Conductor or main earthing lead made of GI Strip of size 32 X 6mm, fixed to wall on batten or recess or chases or burried in ground or fixed to poles or any other indicated situation including drawing through GI Pipe for earthing etc. complete all as specified and as directed.

S & F Test Point Terminal Box of size 200 X 100 X 100mm made out of 2mm thick hot dip galvanised sheet, drilled and screwed including 6 Nos 15mm long hexagonal head screws complete with Test Point Terminal Block made of Gun Metal or Phosphorus Bronze of size 75 X 75 X 25 mm drilled and screwed including 3 Nos 8 mm dia 25 mm long hexagonal head screw complete all as specified and as directed.

Prasur Electricals & Engineering Co.

OPS Associates