SPECIAL REPAIRS TO HT/LT TRANSFORMERS AT NCHC POWAI

Amount

Design, Supply, Erection, Testing and Commissioning of 11 KV, 630A, 21KA for 3sec, SF6 insulated, Manual , Indoor , Right side extensible RMU , type tested in line with latest IEC standards. The RMU shall be suitable for operations at a height up to 1000 meters above sea level and at 40 degree ambient temperature without any derating. The switchgear and busbar shall all be contained in a stainless steel enclosure filled with SF6 at 0.3 bar (300 hPa) relative pressure. The RMU tank shall provide full insulation, making the switchgear insensitive to the environment with degrees of protection of IP67 . The switchgear operating mechanism shall have an IP2X protection and cable chamber shall have IP3X. 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. An operator situated in front, lateral (A-FL 21kA – 1sec, downwards exhaust, for tank as well as cable compartment) of the RMU switchboard during an internal fault will not be exposed to the effects of arcing. Internal Arc Type Test Report for IAC AFL 21 kA for 1 sec for both tank & cable box should have been for minimum 3 way / 3 Function RMU. 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 should only require 450mm to handle and the gap between the coupled RMU’s must be within 10mm. All operations shall be from front of the RMU, including access to cable bushings. Cable bushings along the sides or the rear of the RMU are not acceptable. 11KV, 4 Way Ring Main Units ( CCT2T2) - Two isolator and two breakers Each of the above Ring Main Unit shall comprise of the followings: A. Load Break Switch (LBS) each comprising of the following – 02 Sets (i) 11 KV, 630A, 21KA for 3sec Manual Load break switch; with built in line side manual earth switch. Earthing should be completed within 2 operations only (i.e 1. Main switch - OFF, 2. Earth switch - ON). LBS shall have 3 positions, open or disconnected, closed and earthed, and will be constructed in such a way that interlocking prevents unauthorized operations. For earth switch, manual opening and closing will be driven by a fast-acting /snap action mechanism, independent of operator action. LBS and earth switch shall have a min of 1000 (M1) mechanical operations , and 5 nos closing operations at rated SC current. LBS should have 100 electrical operations at rated current – 01 No (ii) Position indicator through clear front mimic in line with IEC 62271-103 -01 No (iii)Live cable indicator with indications (Voltage Presence Indicator) at the front and three inlets provision to check the synchronization of phases. VPI should be of same make as that of RMU -01 No (iv) Cable box with termination bushing suitable for upto 2 RUN 3Cx300 Sq mm, XLPE cable-01 No (v)Fault passage indicator (FPI) with in-built Overcurrent, Short Circuit and earth fault indication . The FPI should be self-powered and should have internal lithium battery for external indication and setting of FPI in the absence of current. FPI should have 4 digit LCD display, ammeter feature and should be of same make as that of RMU-01 No vi) Cable Boots suitable for actual cable size-01No (vii) Auxilary switch : LBS - 2 NO +2 NC, Earth switch - 1 NO + 1 NC- 01No (viii) Mechanical operation counter -01 No

B. Vacuum circuit breaker (VCB) each comprising of the following -02 Sets (i) 11 KV, 630A, 21KA for 3sec Manual VCB with spring assisted mechanism and series trip coil; with built in manual line side three position disconnector cum earth switch. Earthing should be completed within 2 operations only (i.e 1. Main switch - OFF, 2. Earth switch - ON). Vaccuum interrupter should be of same make as that of RMU. The circuit breakers shall have 2 positions: open or disconnected and closed. A separate and independent 3 position earthing switch and disconnector shall be fitted to open and earth the cables in such way that interlocks prevent all unauthorized operations. An independent mechanism shall be fitted for the 3 positions earthing switch and disconnector. Circit breaker shall have a min of 2000 mechanical and 2000 electrical operations at rated current and 50 nos of operations at rated short circuit current. Disconnector and earthswitch shall have a min of 1000 (M1) mechanical operations. The earthing switch shall be fitted with its own operating mechanism and manual closing shall be driven by a fast-acting mechanism, independent of operator action. -01 No (ii) Position indicator through clear front mimic in line with IEC 62271-103-01 No (iii) Self powered relay with O/C , E/F protection. Relay should have a front USB port for laptop interface , LCD display ,10 event records, 5 fault records with time stamp, min 2 setting group and keypad for setting parameters for the relay. Relay should be of same make as that of RMU – 01 No (iv) Suitable ratio CT 30-75-150/1 A, Class 10P5-5P10-5P10, 2.5VA for protection -01 Set (v) Live cable indicator with indications (Voltage Presence Indicator) at the front and three inlets provision to check the synchronization of phases.VPI should be of same make as that of RMU - 01 No (vi)Cable box with termination bushing suitable for upto 1 RUN 3Cx300 Sq mm, XLPE cable -01 Set (vii) Cable Boots suitable for actual cable size -01 Set (viii)Mechanical operation counter -01 No (ix) Emergency trip push button -01 No C. Accessories (i) Antireflex operating handle -01 no (ii)Manometer -01 No

Design, Supply, Erection, Testing and Commissioning of 11 KV, 630A, 21KA for 3sec, SF6 insulated, Manual , Indoor , Right side extensible RMU , type tested in line with latest IEC standards. The RMU shall be suitable for operations at a height up to 1000 meters above sea level and at 40 degree ambient temperature without any derating. The switchgear and busbar shall all be contained in a stainless steel enclosure filled with SF6 at 0.3 bar (300 hPa) relative pressure. The RMU tank shall provide full insulation, making the switchgear insensitive to the environment with degrees of protection of IP67 . The switchgear operating mechanism shall have an IP2X protection and cable chamber shall have IP3X. 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. An operator situated in front, lateral (A-FL 21kA – 1sec, downwards exhaust, for tank as well as cable compartment) of the RMU switchboard during an internal fault will not be exposed to the effects of arcing. Internal Arc Type Test Report for IAC AFL 21 kA for 1 sec for both tank & cable box should have been for minimum 3 way / 3 Function RMU. 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 should only require 450mm to handle and the gap between the coupled RMU’s must be within 10mm. All operations shall be from front of the RMU, including access to cable bushings. Cable bushings along the sides or the rear of the RMU are not acceptable 11KV, 4 Way Ring Main Units ( CCCT2) - Three isolator and One breakers Each of the above Ring Main Unit of the following A. Load Break Switch (LBS) each comprising of the following – 03 Sets (I) 11 KV, 630A, 21KA for 3sec Manual Load break switch; with built in line side manual earth switch. Earthing should be completed within 2 operations only (i.e 1. Main switch - OFF, 2. Earth switch - ON). LBS shall have 3 positions, open or disconnected, closed and earthed, and will be constructed in such a way that interlocking prevents unauthorized operations. For earth switch, manual opening and closing will be driven by a fast-acting /snap action mechanism, independent of operator action. LBS and earth switch shall have a min of 1000 (M1) mechanical operations , and 5 nos closing operations at rated SC current. LBS should have 100 electrical operations at rated current – 01 No (ii) Position indicator through clear front mimic in line with IEC 62271-103 -03 No (iii)Live cable indicator with indications (Voltage Presence Indicator) at the front and three inlets provision to check the synchronization of phases. VPI should be of same make as that of RMU -01 No (iv) Cable box with termination bushing suitable for upto 2 RUN 3Cx300 Sq mm, XLPE cable-01 No (v)Fault passage indicator (FPI) with in-built Overcurrent, Short Circuit and earth fault indication . The FPI should be self-powered and should have internal lithium battery for external indication and setting of FPI in the absence of current. FPI should have 4 digit LCD display, ammeter feature and should be of same make as that of RMU-01 No vi) Cable Boots suitable for actual cable size-01No vii) Auxilary switch : LBS - 2 NO +2 NC, Earth switch - 1 NO + 1 NC- 01No (viii) Mechanical operation counter -01 No

B. Vacuum circuit breaker (VCB) each comprising of the following -01 Set (i) 11 KV, 630A, 21KA for 3sec Manual VCB with spring assisted mechanism and series trip coil; with built in manual line side three position disconnector cum earth switch. Earthing should be completed within 2 operations only (i.e 1. Main switch - OFF, 2. Earth switch - ON). Vaccuum interrupter should be of same make as that of RMU. The circuit breakers shall have 2 positions: open or disconnected and closed. A separate and independent 3 position earthing switch and disconnector shall be fitted to open and earth the cables in such way that interlocks prevent all unauthorized operations. An independent mechanism shall be fitted for the 3 positions earthing switch and disconnector. Circit breaker shall have a min of 2000 mechanical and 2000 electrical operations at rated current and 50 nos of operations at rated short circuit current. Disconnector and earthswitch shall have a min of 1000 (M1) mechanical operations. The earthing switch shall be fitted with its own operating mechanism and manual closing shall be driven by a fast-acting mechanism, independent of operator action. -01 No (ii) Position indicator through clear front mimic in line with IEC 62271-103-01 No (iii) Self powered relay with O/C , E/F protection. Relay should have a front USB port for laptop interface , LCD display ,10 event records, 5 fault records with time stamp, min 2 setting group and keypad for setting parameters for the relay. Relay should be of same make as that of RMU – 01 (iv) Suitable ratio CT 30-75-150/1 A, Class 10P5-5P10-5P10, 2.5VA for protection -01 Set (v) Live cable indicator with indications (Voltage Presence Indicator) at the front and three inlets provision to check the synchronization of phases.VPI should be of same make as that of RMU - 01 No (vi)Cable box with termination bushing suitable for upto 1 RUN 3Cx300 Sq mm, XLPE cable -01 Set (vii) Cable Boots suitable for actual cable size -01 Set (viii)Mechanical operation counter -01 No (ix) Emergency trip push button -01 No C. Accessories (i) Antireflex operating handle -01 no (ii)Manometer -01 No

Taking down existing 11/433 V step down distribution transformer by disconnecting HT and LT cables on both sides of the winding and keeping the transformer at substation store room with proper wheel locking for not to rolling down complete all as specified and directed.

Supplying, installing, connecting, testing & commissioning of Three Phase 11KV/433Volts Distribution Step Down,Indoor, Transformer of Rated capacity 500 kVA as per IS 1180-(Part-I): 2014, with energy efficiency level No 3, Oil immersed type,Copper wound, Indoor type, ONAN type cooling, connection symbol Dyn11, HT winding with delta connected, LT winding with star connected with neutral brought out, HT (11 KV, 3 Phase, 50 Hz), LT (433 Volts 3 Phase 4 wire), with off load tappings on HT side to vary secondary voltage to +5% to -10% within limit all as per IS-1180 amendemnets 1,2,3 and 4, 02 Nos body earthings complete Mounted over the Existing foundation complete as specified and as directed. The Accessories needed of the transformer shall be following below are, (a) Rating and Terminal Marking Plate,(b) Lifting Lugs,(c) Oil Level Indicator with Minimum marking,(d) Roller Unidirectional with Locking arrangement,(e) Pressure Relief valve,(f) Dehydrating breather,(g) Drain valve and Filter valves with blanking plates,(h) Stem type thermometer.(i) Conservator oil Tank Note - The new Transformer shall be manufactured and tested at OEM factory.

Taking out existing HT VCB panel disconnecting HT cables from in coming, out going and transformer and VCB panel and panel shift at substation store room complete all as specified and directed.

Supply, Installation, testing and commissioning HT panel -11 KV, 630A , 3 Phase, 50 Hz, 3 wire ( As per IEC 62271-100/200) totally enclosed, pre wired, metal clad, indoor type, floor mounted, Horizontal isolation type vacuum circuit breaker (VCB) 630 Amp rating having rupturing capacity ( Max 26.2 KA 3 Sec) with copper Bus Bar , The panel should be tested for interal arc for 25 KA or above for 1 sec. The breaker of the offered new outgoing panels should be interchangeable with the existing breaker at NCHC Powai Sub station No -02 for any emergency . Qty of panels - Two nos incomer panels for receiving two incomer supply. Both incomer panels should have electrical interlocking so that only one incomer will be operational at one time. Suitable relay having under voltage function should be given for achieving the electrical interlocking . The side cable box should be supplied by OEM for mounting of Transformer cable from side of incomer panel. ( As per the existing panel configuration available at site) Following items are required for outgoing feeders - (a) Panel enclosure - The panel enclosure should be made of Aluzinc sheet . Only the front door and rear cover be made of CRCA sheet by OEM manufacturing unit. (b) Mechanical inter lock and automatic safety shutter gear 1 No (c) Isolating plugs - 6 Nos (d) 11 KV, 630 Amps max 25 KA at VCB -01-No ( comprising of the following:- (i) Assembly of 1 nos vacuum interrupters ( The make of the vacuum interrupter should be same as make of VCB) (ii) Hand and motor operated spring charged, independent starting, tripping trip free operating mechanism with manual closing and tripping push buttons. (iii) Mechanical operation counter- 1 nos (iv) Closing and Tripping coil. -1 no (v) Breaker operated auxiliary switch 6 Nos and 6 N/C (vi) Bus bar chamber including set of 3 phase 630 Amps Copper bus bar. - 01 Set (e) 230 V AC Single phase, 80W rated strip type heater-2 Nos (g) Current transformer chamber incorporating 3 single phase resin cast CTs of ratio 50/1 Amps with suitable VA burden and accuracy class 1 and 5P10 -01 No (h) Rear cable termination, provision for terminating cable Contd.....

(i) Digital Ammeter - 01 No (k) On/off/Trip indication - 01 No (l) 3 phase RYB indication with lamps - 01 No (m) TNC Switch - 01 No (n) Trip circuit supervision healthy indication lamp - 01 No (o) Digital Multifunction meter Model EM 6400 Accuracy Class -1 - 1 no (p) Necessary separate power pack for each switch gear (The 230 V AC supply is available at site) (Q) Numerical relay - Earth fault , over current, under voltage function having suitable protection setting range ( Schneider make) -01 no ( r) One no hygrostat to be provided in each Panel ( R) Aux relay for transformer protection-01 Set ( s) Temperature sensors ( battery less, wireless and sensors should be suitable to mount/place directly on the live bus connection to get the max accuracy. ) for monitoring of bus side ( RYB phase) and cable side ( RYB) temperature - 6 nos for each outgoing panel only (T) - Humidity Sensor - One no Humidity sensor to be provided in S/S All temperature sensor and humidity sensor data will be monitored through common Local HMI to be provided on one no HT panel. The Sensor shall be approved according to IEC Standard 61010-1, IEC Standard 60068-2-6(SEP1001 - Vibration Test) and IEC 68-2-31 (SEP1002 - Drop Test), IEC 60068-2-27 (Shock Test), IEC 60721-3-3 (Shock Test), and UL Standard 61010-1. t) Illumination lamp with Power socket (U) Master trip reay - 1 no Note - (i) The breaker of the new switchgear should be interchangeable with the existing breaker at NCHC Powai Sub Station -02 (ii) The new switchgear shall be OEM make and to be offered for Factory Acceptance Test at OEM factory. The system integrator, panel builder panels are not acceptable. (iii) The make of the vacuum intrupter should be same as make of VCB. (iv) The design should have top and bottom separate arms in breaker. The breaker having single arm design with vacuum bottle in horizontal position shall not be acceptable. Vendor to quote new design of switchgear where this type of arrangement is not applicable.

Supply and fix cable jointing kit for 11 KV grade cable for end termination joint , heat shrink type, joint complete with jointing material and accessories suitable for 3 core XLPE, armoured, aluminium conductor cable of size up to 120 sqmm complete all as specified and directed.

Supply and fix cable jointing kit 11 KV (earthed) grade cable for straight through, heat shrink type, joint complete with jointing material and accessories suitable for 3 core XLPE, armored, Al conductor cable of size 95 sqmm to 120 sqmm complete all as specified and directed.

Supply, laying & testing cable XLPE insulated, screened, PVC bedded, galvanized steel strip or wire armored, electric power cables (heavy duty)with stranded aluminum conductor, 11000 volts grade, of size 3 core 120 sq mm. Note :- New Cable laid hence no sch of credit consider.

Excavation in trenches not exc 1.5m wide and not exc 1.5m depth in soft/loose soil for foundation or laying of cable and getting out etc complete all as specified and directed.

Returning filling, including spreading leveling, watering and well ramming in layers not exc 25cm thick etc complete all as specified and directed

Removal of excavated material (soil) n. exc 50 mtr and depositing where directed etc complete all as specified and directed.

Material and labour for filling fine, river sand for sand cushioning in trenches for cable protection all as specified and directed. (Note : Punned thickness only will be measured and paid).

Material and labour for un-reinforced pre-cast concrete cable cover class HV type-1, flat of size 300mm x 180mm x 40mm etc complete all as specified and directed.

M & L for Earthing complete with galvanized steel earth plate electrode 60cm×60cm× 6mm thick, buried directly in ground (earth pit not less than 2.25 metres deep below ground level) with top edge of the plate not less'than 1.5 metres below normal ground level, connected to galvanized earth lead using galvanized iron strip 25×4mm as earthing lead by means of bolts, nuts, check nuts and washers of galvanized iron or steel all as shown in electrical plate No. 3 connected to earthing test point all as specified or indicated including testing on completion.

M&L for PCC 1:2:4 type B-1 (using 20mm graded crushed stone aggregate) as in coping / foundation of RMU including use of form work and finishing all exposed faces of concrete as per clause 4.11.16.2 (a) & (d) of SSR Part-I complete complete all as specified and directed.

Supply and fixing Pre cast RCC Joint indicator of size of 250 x 150 mm at bottom 200 x 150mm at top and 1250 height fabricated in cement concrete of 1:2:4 surface should be sooth finished. The word "HT Cable" should be engraved on the route indicator of letter size 500mm complete all as specified and directed

RAVINDRA BROTHERS

cooltech engineering services

United Sales Corporation

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Radha Engineering Services