PROVISION OF 11 KVA AVR FOR MAFI ELECTRIC NETWORK SYSTEM AT MAIN RECEIVING STATION OF GE (AF) AT AFS YELAHANKA

Supply, Installation, Testing and Commissioning of HT 11 KV, AVR 630 KVA, 3 Phase, 50 Cycles, Outdoor type, Copper wound with Class ‘A’ insulation, On load step less rolling contact type voltage regulator, auto wound delta connected booster transformer double wound open/open automatic control gear consisting of one electronic relay design oil cooled with input 9 KV to 12 KV and output 11 KV (+/-) 1% with lifting lugs and Swivel type rollers, Two Nos earthing terminals, rating plates indicating details, Buckholz relay, first fill of oil, oil and winding temperature gauge, Alarm and LED lamp indicating Input Voltage exceeding specified range complete and including necessary interconnection with LT UG Cable of AVR & Booster Transformer all as specified and as directed with following specification :- (a) Basic Insulation level 28 KV for 1 minute. (b) Type of cooling ONAN (c) Correction speed 200V / Second (Minimum) (d) Duty cycle 100% continuous load. (e) Suitable for balanced/unbalanced load. (f) Power loss shall be less than 1% or as specifed by OEM (g) Voltmeter for Input voltage for 3 phase, auto manual function selector switch. (h) Magnetic core shall be made of cold rolled grain oriented low loss steel stampings. (j) Control and monitoring system with alarm, lamps to Indicate Input Voltage exceeds limits of specified range Voltmeter to Indicate output Voltage for 3 phase separately Auto / Manual change over switch. A switch to raise and lower Voltage in manual position.

(k) Tab limit switch in order to avoid over running highest and lowest position chain drive coupling devices and all electrical connection. Hand Control, Hand wheel will be located on the front of the regulator tank at convenient operative height. Motor Control Raise / lower push button control by means of small single phase reversible geared motor of the permanent capacitor type shall be provided. The limit switches shall be provided to restrict the travel at extreme position with this arrangement, it wound also be possible to provide remote control of the Regulating unit. The reversible geared motor wound of ‘STEP-SYN’ type. Automatic Control Automatic correction of fluctuating supply voltage are shall provide electronic relay which will sense the output voltage and provide signal to the driving motor for necessary corrections. Notes: Rate shall be for the complete board including base frame, cutouts, foundation bolts. All necessary interlocking arrangements to be provided as per standards and as indicated in the drawings.

Supply and fixing 11 KV operating voltage, 21 kA for 3 seconds, 3 phase 50 Hz, IP 54, SCADA compatible, motorized, three way Ring Main Unit comprising Two number vacuum circuit breakers duly interlocked and one number motorised load break isolator, battery chargers, totally enclosed metal clad switch gear with motorized with battery and charger, protection relays, having rated current of Ring Switch and Breaker is 630 Amp, One side extensible, with internal arc classification with AFLR with 21 kA for 1 second, copper bus bar with danger notice board, with factory made weather proof enclosure by the switchgear manufacturer. The unit shall be painted in RAL 7032 / 7035 paint shade with following specifications and all as per the IEC 60298,IEC 60265, IEC 60129, IEC 60420, IEC 60056, IEC 60694 and as per the specification of the manufacturer. (a) Ring Switch/Isolator: (i) Capacity 11 KV, HT, 630 Amps. Triple pole, single break, having three position ('ON', 'OFF' and 'EARTH') Ring Main Switches, each with independent motor charged spring mechanism and fully rated earth switch. (ii) Air insulated cable boxes with gland plate suitable for bottom entry of single run of three core cable up to 300 sqmm. (iii) Cable Bushings (iv) Capacitive Voltage Indicator with LED Display. (v) Mimic diagram on front panel, complete with status indicators (ON-OFF-EARTH). (vi) Motor for motorised operation. (vii) One set of Potential Free contacts for SCADA Compatibility. (viii) Fault Passage Indicators (ix) One set of Right Angle Boots-NON TOUCH PROOF

(b) Vacuum Circuit Breaker : (i) Capacity 630 Amps, Triple pole, Vacuum Circuit Breaker, with independent motor charged spring mechanism and fully rated earth switch, with provision for earth of the cable. (ii) Air insulated cable box with gland plate suitable for bottom entry of single run of 3-core cable up to 300 sqmm. (iii) Multi powered Over current, Earth Fault and short circuit three element numerical Relay. (iv) Resin cast current transformers for protection mounted CT ratio 40-80/1A, 5P10, 2.5VA. (v) Capacitive Voltage Indicators with LED Display. (vi) Mimic diagram on front panel, complete with status indicators (ON-OFF-EARTH). (vi) Motorised assembly. (vii) Epoxy Molded low energy Tripping Coil for tripping the circuit breaker in fault condition. (viii) Right Angle Boots-NON TOUCH PROOF. (c) General specifications: (i) One set of positive standard electrical/mechanical interlock to avoid unsafe operations. (ii) Provision of pad locking for open, close, earth position in correct sequence. (iii) Monometer for indicating SF6 gas pressure with green and red zone. (iv) 2.5 mm thick stainless steel SF6 tank with robotically welded construction with IP67 protection. (v) External stud for earthing connections. (vi) One no of Operating Handle.

Excavation in trenches not exceeding 1.5 m wide and not exceeding 1.5 m deep for laying of cables, pipes, foundation for poles etc., and getting out in hard/dense soil all as specified and as directed.

Returning filling in excavated soil upto a depth of 30 cm after riddling of excavated soil (in lieu of sand) for cushioning of cable and refilling of trenches with left over normal excavated soil including spreading, leveling, watering and well ramming in layers complete all as specified and as directed

Removing surplus soil to a distance not exceeding 50 m and depositing where directed at a level not exceeding 1.5 m above the starting point as directed.

Supplying and laying un-reinforced precast concrete cable cover, class HV, Type 1 with peak, size 300 mm x 180mm x 40mm all as specified and as directed.

Supply and laying & Testing cable XLPE insulated screened PVC Bedded galvanised steel strip or wire aromoured electric power cable (Heavy duty ) with stranded aluminium conductor , 11000 Volts grade of size 240 Sqmm 3 Core complete all as specified and directed.

Supply and laying & Testing cable XLPE insulated screened PVC Bedded galvanised steel strip or wire aromoured electric power cable (Heavy duty ) with stranded aluminium conductor , 11000 Volts grade of size 120 Sqmm 3 Core complete all as specified and directed.