DISTRIBUTION TRANSFORMER

Transcription

1 ELECTRICITY COMMISSION PLANNING AND STUDY DEP. BAGHDAD, REPUBLIC OF IRAQ Annex A SPECIFICATION No. D-26 DISTRIBUTION TRANSFORMER 61410/11kV REVISION YEAR 2001

2 DISTRIBUTION TRANSFORMERS 1- SCOPE OF THE TENDER : Tenderer are invited for the design, manufacture, testing and supply of a 11000/416 volt,oil immersed copper winding outdoor type (Directly under the sun) transformers to be supplied complete with all necessary fittings, accessories offload tap changer, insulating oil and spare parts... etc. The transformer is to be hermetically sealed (without conservator tank)bolted cover with bushing insulators on both H.T and L.T sides for the following rating : 100, 250, 400, Box type for rating 630 and 1000 KVA. And a valid ISO 9001 certificate. 2- GENERAL REQUIREMENTS : The transformers shall be of first class quality and design for continuous satisfactory operation as continuity of supply is of prime consideration. the design shall be allow all necessary precaution for the safety of operation and maintenance personnel. the transformers shall operate satisfactorily under variations of load, voltage or short circuit or other conditions which may occur on the system provided that these variations are within the assigned rating of the apparatus. All the equipment shall be designed to obviate the risk of accidental short circuit. 2-1 Climatic Conditions : The materials used shall be suitable for the following climatic conditions prevailing at the site: Ambient temperature: Highest maximum (in the shade) +55C for about 6 hrs a day. Lowest minimum 10C Maximum yearly average+30c Maximum daily average +40C Sun Temperature: Black objects under direct sunshine attain a temperature of 80 C Air humidity : Maximum 92% at 40 C Minimum 12% Yearly average 44%

3 2-1-4 Sand storm: In general the atmosphere is dusty which may result in a layer of dust being deposited on all exposed surfaces. Also fine dust particles may penetrate even through minute openings. 2-2 Altitudes From sea level up to (1000m) 2-3 System Data: High voltage side:- Nominal voltage Short circuit level Frequency Highest system voltage system Low voltage side:- Nominal voltage: 416/240 volts s ystem Short circuit level Volts 25 KA at volts 50 HZ volts 3- phase,3-wire with neutral isolated but provision is made for earthling through an earthling resistance of 21.1 ohms to limit the earth fault current to 300 Amp. phase,4-wire neutral solidly earthed. According to the short circuit level of H.T side and the rated power of the transformer 2-4 Standards: All the equipments shall be in accordance with the latest issue of the international Electro technical commission (IEC specification). 2-5 Deviation: The tenderer shall particularly mention in his tender all deviations from the specification described in these tender specification. 2-6 Schedules: The tender shall duly fill in the schedules A&B of guaranteed technical particulars, prices, delivery and deviations attached to this specification. Incomplete tenders are liable to rejection.

4 2-7 Guarantee: The tenderer shall confirm than the transformer guaranteed against all defects arising from faults design, materials and workmanship, for a period of (12) months from commissioning or (18) months from arrivals, whichever period expires earlier. 3- system composition The transformer shall operate in distribution systems where most of the net work is overhead lines and comprising partly underground cable. 4- TECHNICAL SPECIFICATION The transformers shall be copper winding. Hermetically sealed of the blolted cover and should have the following characteristics:- Rated outputs ONAN. 100, 250, 400, 630, and 1000 KVA. Duty.step-down, outdoor bushing type for 100,250,400,Box type for 630 & 1000 KVH. Type wound, 3-phase Rated voltage at no load. H.V. 11kv L.V- 416 volt. System frequency 50HZ Interphase Connection H.V. Delta L.V- star with neutral brought out. Vector relation ship Dyn 11 Type of Cooling. ONAN Temperature rise ( i ) 45 C in top oil by thermometer (ii) 50 C in winding by resistance. Off circuit tapings five tapping for 2.5% - 5% on the H.T winding for off circuit operation externally. The machine must be of the robust and definite position type with a click indicating position arrived during tap changing. System Highest Voltage.. H.V side 12 kv Terminal arrangement of transformers:- The 11 kv side terminal is to be a clamp type with eyebolt and nut suitable for conductors up to 150 mm 2 copper. The low voltage terminal are to be flat bar type with holes suitable for compression type thimble the sizes of L.V side: For 100 KVA transformer 4x1x70 mm 2 copper. For 250 KVA transformer 6x1x mm 2 copper For 400KVA transformer 7x1x150 mm 2 copper For 630 KVA transformer 11x1x240 mm 2 copper For 1000 KVA transformer 14x1x240 mm 2 copper

5 Terminal arrangement of outdoors transformers must be brown colored bushing insulator mounted on the top cover of transformer for both H.T. and L.T, with arcing horn on H.T.bushing for outdoor transformer only. Neutral bushing should distinguished from phase bushing, - For box-type transformer a suitable iron box cover the top bushings. 5- Fittings and Accessories: - Terminal marking plate. - Tapping switch. - Valves 3 / 4 B.S.P fitted on cover and bottom of tank, switch cocks. - Thermometer pocket. - Lifting lugs. - Pressure relief valve. - Earthling terminal on tank. - Rating and diagram plate to be chromium plated of the engraved type. - Skid mounting to be vertical with the length of the transformer. - Oil level indicator, to be of mechanical type located on the top cover of transformer to avoid oil leakage, covered by metallic envelop. 6- painting A primary coat shall be applied immediately after cleaning all ungalvanized metallic parts thoroughly. An oil and weather resistant type second coat shall then be applied and the transformer finished in aluminum paint. 7- insulating oil The transformer is to be shipped with first filling of oil which shall be SHELL DIALA (B). 8- loss evaluation The tolerance permitted is +10% of the evaluated guaranteed total losses mentioned in the offer. Any transformer with total losses more than + 10% will be rejected. For transformer with total losses within +5% of the evaluated guaranteed losses, no variation to the contract price shall be made, for transformers where the total losses between 105% to 110% of the total evaluated guaranteed losses, the contract price shall be reduced by the cost of the difference between the total losses and the 105% of the total evaluated guaranteed losses according to the following values. Iron losses 1800 USD per kw. Copper losses 600 USD per kw. For any transformer with total losses less than 100% of the guaranteed losses, no variation to the contract price shall be made.

6 9-1 Inspection: 9- Test The material shall be subjected to inspection and test by our inspectors or international inspector at any time during manufacture. The manufacture shall provide all inspection facilities for the said inspection and inspection shall be made at the place of manufacture or at international testing facilities. The inspector shall have the right of rejecting any portion of the material at any time during manufacture if it dose not meet with the requirements of this specification in all particulars. He shall have the right of overseeing the packing and shipping of all material to be supplied. 9-2 Test at manufacture work: Test at manufacture s work shall comprise type tests if required and routine tests. a-type tests The type test prescribed shall be carried out on one unit of each capacity 1- Test of temperature rise clause 41 of IEC 76/ Full wave impulse-voltage withstand test clause test 45 of IEC 76/ Cost of these tests to be borne by the manufacturer. b- Routine tests Each transformer shall be subjected to all the routine tests specified in section twelve of IEC 76/ Test reports: Five copies of the test reports will be mailed within 8 days after the tests have taken place. These reports will indicate: - The results of the tests. - The calculation of performance of the items. - The guarantee figures to show that each apparatus performs the conditions of the specification within the guaranteed limits. 9-4 Test Certificates: The tenderer shall furnish the Electricity Commission (EC) with 6 copies of test certificates. No equipment shall be shipped without obtaining the (EC) inspector prior approval of the certificates.

7 9-5 Witnessing tests: Unless otherwise agreed to, all tests at factory shall be witnessed by an authorized representative of our (EC). The cost of travelling & accommodation of required authorized engineers to witness the test at the place of manufacture for required days, to be on tenderer account. 10- Drawing, Instruction Book And Litreature document to be submitted with the tender: The following documents shall be submitted by the tenderer along with his tender:- a- full and technical specification of transformer including schedule A&B of guaranteed technical particulars. b- An outline drawing showing the plan, front and side elevation of the transformers, dimensions, terminals, equipment, and all accessories of the transformers. c- Catalogues of the manufacturer for transformers. d- Valid ISO-9001 certificate of the manufacture r for transformers. e- Test certificate for identical transformers. f- Reference list of manufactured and exported transformers. g-incomplete tenders are liable to rejection Document to be furnished by the successful tenderer: Within a period of 4 months from the date of award of the contract, the successful tenderer shall furnish the (EC) with the following documents:- a- 24 sets of prints on paper on all drawings. b- 24 copies of all instruction books and technical maintenance of the transformer, OFF Load tap changing gear and other ancillary equipments. c- 24 copies of instruction for erection of the equipment. d- 24 copies of spare parts list with catalogue number Language: The language to be used in the drawings and instruction book shall be English Dimension: Due to the space requirement in our system it is important for the participants in this tender to make sure that the dimension of each type of the

8 required transformers to be as small as possible the following table is indicative as a maximum for each single dimension:- Table of Dimension Transformer KVA Length MM Width MM Height MM Approval of drawings: The successful tenderer shall prepare and submit to the (EC) all necessary drawings complete with explanations in due time and obtain approval of the same before commencing manufacture. Failure to comply with this clause shall make the equipment or parts or parts there of liable to rejection. 11- Packing The supplier will pack or protect the goods in the most appropriate manner. He will be responsible for any loss or damage arising from careless packing or protection up to the place of final destination after completion of the inspection and tests at the factory, each item shall be packed for export shipment. All parts provided for shipping purposes only and which are to be removed at the time of erection shall be conspicuously tagged. The method of packing shall be such as to protect all the items against excessive corrosion of dampness, and shall afford adequate protection against breakage or other injury, or loss due to breakage of cases or crates from the time the items leaves the factory until finally installed at the substation during which time, the apparatus will travel by rail by a long sea voyage again by rail or truck to the site of the substation. The equipment will also undoubtedly stand on wharves and in the open during and in between periods of transportation and will thereby be exposed to heavy rain, hot sun, humid climate and sudden changes of temperature. Owing to the numerous handlings, the containers should be very strong also extra ordinary care should be given to the packing of the equipment and especially the items having insulating material to prevent the injury due to moisture, from sources external to the packing or from excessive condensation with the packing.

9 12- Spare parts and special tools for each rating 12-1 Spare parts: 1- H.T / L.T winding. 3% 2- H.T bushing with it s accessories. 10% 3- L.T bushing with it s accessories. 10% 4- Tap changer. 3% 5- Pressure relief valve. 2% 6- Oil level indicator. 10% 7- Cover gasket 10% Unit price per set and per piece for each item are required Special tools: All special tools required for maintenance of transformer shall be included in the scope of supply. An itemized list of special tools together with prices shall be submitted with the tender.

10 SCHEDULE ((A)) SCHEDULE OF THE GUARANTEED PERFORMANCE AND OTHER TECHNICAL PARTICULARS (TO BE COMPLETED BY THE TENDERER) Unit KVA KVA KVA KVA KVA Tr. Tr. Tr. Tr. Tr. 1- Name of manufacturer. 2- Country of origin. 3- Standard on which performance data is based. 4- Continuous maximum rating for the specified. Temperature rise and ambient temperature ( valid clause 5 (1) ONAN rating-(kva) 5- Rated temperature rise ( C ) a- Oil by thermometer. b- Winding by resistance 6- Hottest spot temperature-(c). 7- No-load voltage ratio at normal tap & vector relationship> 8- Exciting current referred to H.V. and 50 c/s and at.. (Amps) a- 90% rated voltage. b- 100% rated voltage. c- 110% rated voltage. 9- Power factor of exciting current at100% rated voltage and 50 HZ.. (%). 10- Iron losses at 50 HZ and at.. (kw). a- 90% rated voltage. b- 100% rated voltage. c- 110% rated voltage. 11- Copper losses at full load (O.N.rating) and at 75 C (kw) 12- Total losses.. (kw). 13- Resistance voltage at full load and at 75 C (%). 14- Reactance voltage at full load and at 75 C... (%) 15- Impedance voltage at full load 75 C... a- At normal tap. b- At highest tap. c- At lowest tap. 16- Resistance of H.V. winding per phase at 20 C -(ohms). 17- Resistance of L.V. winding per phase at 20 C -(ohms). 18- regulation at full load at 75 C a- 1.0 power factor. b- 0.8 P,F lagging. 19- Efficiency at 75 C -(%) a- 100% load b- 75% load

11 c- 50% load d- 25% load 20- Calculated thermal time constant -(Hrs). 21- Maximum flux density at normal voltage and frequency and at normal ratio - (KI/sq.cm) a- core b- yoke 22- Maximum flux density at 110% voltage and frequency and at normal voltage and frequency and at normal ratio a-core b- Yoke 23- Insulation of a-core bolts b- Core bolts washer c-side plates d- Core laminations 24- Current destiny in windings Amps/sq.cm. a- H.V. winding b- L.V. winding 25- Insulation on copper 26- insulation strength of winding. a- Impulse full wave -(kv) ( I ) H.V. (I I ) L.V. b- Impulse chopped wave -(kv) ( I ) H.V. (I I ) L.V. c- Applied voltage test. -(kv) d- Induced voltage test. -(kv) 27- Insulation strength of terminals. a- Over voltage test -(kv) b- Minimum wet withstand voltage. -(kv) c- Minimum impulse withstand. -(kv) d-minimum puncture or oil-immersed withstand voltage. -(kv) 28- Type of core 29- Tap changer a- Manufacturer b- Type c- Step of one tap in per cent of rated voltage 30- Thickness of transformer tank (mm) a-sides b-bottom c-corrugated radiators

12 (i) (ii) 31- Weights and dimensions a-net weight of core b-net weight of copper H.V. L.V. c-net untanking weight of -(Kg) -(Kg) (i) Core -(Kg) (ii) Frame -(Kg) (iii) Coil -(Kg) d- Volume of insulating oil -(IMP.Gall) e- Net weight of insulating oil -(Kg) f- Total weight of transformer less oil -(tons) g- Weight of the largest shipping package -(tons) h- Crane lift for untanking core and coils -(m) i- Crane lift for removal of bushings -(m) j- Dimensions of transformer -(m) (i) (ii) (iii) (iv) Under base to top most point Under base to bushing mounting flanges Overall breadth Overall length k- Overall shipping dimensions of tee largest package. 32- Noise level..db.

13 SCHEDULE B OIL CHABACTERISTICS TABLE (TO BE COMPLETED BY THE TENDERER) NO. DESCRIPTION UNIT SPECIFICATIONS 1. MAKER S NAME 2. REFERENCE NAME OF OIL 3. SLUDGE VALUE 0% 4. FLASH POINT (CLOSED) C 5. POUR POINT C 6. VISCOSITY AT 21 CST 7. ELECTRIC STRENGTH(BREAKDOWN KV VOLTAGE) 8. ACIDITY(NEUTRALIZATION VALUE) -TOTAL mg/koh/g -INORGANIC 9. SAPONIFICATION VALUE mg/koh/g 10. COPPER DISCELERATION 11. CRACKLE 12. SPECIFIC GRAVITY 13. SULFER CONTENT 14. DIELECTRIC DISSIP ATION FACTOR (tend)

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35 Ministry of Electricity Planning and Studies Office Baghdad Iraq Specification No. D-02 TECHNICAL SPECIFICATION OF 33/11KV MOBILE SUB-STATION 1 10MVA 1 16MVA REVISION YEAR 2001 YEAR 2009

36 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA 1. GENERAL 1.1 SCOPE OF WORK: Tenderers are invited for the design, manufacture, testing and commissioning, of trailer mounted 33/11.5 KV 10 MVA and 16 MVA mobile substations to be supplied complete with all necessary fittings accessories according to attached single line diagrams. spare parts and a valid ISO 9001 certificate for power transformer and (33KV, 11KV) switchgear i.e circuit breakers and their switchboard, to be submitted with tender documents, otherwise the offer will be rejected. 1.2 STANDARDS The applicable standard to design the equipments and accessories shall be the latest IEC recommendation. 1.3 SCHEDULES The tenderer shall duly fill in the schedules of guaranteed technical particulars, prices, delivery time schedules and deviations attached to this specification. Incomplete tenders will be rejected. 2. General Requirements: The materials shall be of first class quality and designed for continuous satisfactory operation as continuity of supply is of prime importance and to operate satisfactorily under variation of load, voltage and short circuit or other conditions which may occur on the system provided that these variations are within the assigned rating of the apparatus. The materials used shall be suitable for the following climatic conditions: 2-1 Ambient temperature: Highest maximum (in the shade) 55 C for about 6 hours a day Lowest minimum (-10) C Maximum yearly average (+30) C Maximum daily average (+40) C 2.2 Sun Shine temperature: Black objects under direct sunshine attain a temperature of 80 C 2.3 Air humidity: Maximum 92% at 40 C Minimum 12% Yearly average 44% 2.4 Altitudes: From sea level up to (1000m) 2.5 Sand storm: The equipments shall be suitable for outdoor installations and subjected to frequent sand storms and heavily polluted atmospher. (1-21)

37 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA 3. TECHINCAL REQUIREMENT 3.1 System Data a- 33 KV system Nominal voltage Highest system voltage System Short circuit level b- 11 KV system Nominal voltage Highest system voltage System Short circuit level volts volts 3- phase, 3 wire,50hz 25 KA r.m.s at volts volts volts 3-phase,3 wire with neutral earthed through an earthing resistance of 21.1 ohm to limit earth fault current to 300Amps. 25 KA r.m.s at volts c-l.t.system Nominal voltage 416 volts + 6%, -10% System 3- phase, 4 wire with neutral solidly earthed Short circuit level 35 KA r.m.s at 400 volts 4. GENERAL SPECIFICATION OF THE SUBSTATION : 4.1 The substation is to include the 33 kv switchgear, 33/11.5 KV transformer, 11 kv switchgear, 33 kv &11 kv cables on drums, with all necessary accessories to complete in working condition. 4.2 The 33 kv & 11 kv switchgear is to be contained in an outdoor kiosk and the transformer to be of outdoor type. Mobile substation maximum height 4.5 meter. 4.3 The kiosk type is to be sheet steel with double layers, rock wool or any alternative of thermally insulating material in between roof and walls for thermal insulation to with stand the local ambient conditions. Kiosks to be air-conditioned. 4.4 The complete unit must be transportable as a single unit. The structure should be fixed to a rigid frame and base ensuring successful operation and transportation. 4.5 The trailer should be according to the relevant international standard and it is to be coupled to a truck. The trailer should be made steel framed, reinforced, complete with all necessary equipment (such as rear light, breaks, flashers, wheels. etc). The trailers have to be designed for heavy road conditions to prevent the damage of substation equipment during transportation. The trailer should be low-bed type with three axles for maximum permissible load. One axle in front to support the trailer It should be designed with suitable connection to 6x4 tractor (tractor is out of scope) Four number of heavy lifting jacks. Two spare tires. 4.6 Station fire extinguisher shall be of the portable type using suitable chemicals for the electrical fire extinguishers. The size shall be determined by the tenderer to suit the type of the equipment. 4.7 Normal indoor and outdoor lighting & sockets 4.8 In case of internal arc fault a safety diaphragm to relief the pressure caused by the arc outside the kiosk. Degree of protection between compartments should be IP40 in the switchgear. 5. INSTRUMENT AND PROTECTION TRANSFORMERS : 5.1 CURRENT TRANSFORMER: In general the instrument and protection current transformer must comply with the IEC and dry type. Three secondary winding of the CT s for 33 & 11 kv circuit one for over current and earth fault protection and the other for measurement shall be designed for rated (2-21)

38 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA current of 5 AMP. The third shall be designed for differential protection with rated current of 1 AMP. Of special class with suitable accuracy class and a saturation factor protecting the instrument in case of short circuit in the main installation, and the protective CT shall ensure correct operation up to the maximum fault current which can be attained or any developed C.T to fulfill the above requirements. 5.2 VOLTAGE TRANSFORMER : In general the voltage transformers must comply with the IEC And dry type. The secondary voltage shall be 110 Volts between phases. The PT should be of suitable accuracy class and protected by means of easily accessible fuses on H.T side and M.C.B on L.T side The voltage transformers used for earth fault indication and metering shall be of three single phase double wound (star/ star) type with a tertiary winding connected in open delta the secondary star winding shall be used for visual indication of earth fault and for metering, the open delta winding for operating an audible alarm or trip of earth fault on the 11 kv side. 6. INSTRUMENTS AND RELAYS : All indicating instruments must be water and dust proof designed for tropical climate and capable of continuous operation at full load current as well by fault current. All relays shall be of ELECTRONIC type. Relays shall be of withdrawable type to carry out routine tests in service. and for early replacement. Additional protection relay without auxiliary supply or supplied through capacitor storage unit shall be added to operate the protection when there is no D.C supply in the substation. 7. PROTECTION RELAYS: 7.1 ALL panels shall be provided with over current and earth fault relay (2 O/C + 1E /F) of IDMTL type as follows:- Time range 0 3 sec. Current setting for O/C % In Current setting for E/F 5-40% In Instantaneous element %(when required) 7.2 Under voltage relay on the 33kv side to trip the 33kv C. B. in case of supply voltage failure. Earth fault alarm relay self rest of two normally open contact for local and remote alarm should be connected to the open delta winding of V.T on the 11kv side. 7.3 Transformer Neutral point. this protection shall be definite time earth fault relay connected to the C. T. of the neutral earthing resistor to make trip of 33kv C.B, in case of earth fault 7.4 Differential protection for the transformer. 8. SWITCHGEAR: 8.1 The switchgear shall comply with IEC 60289, completely metal- clad type with suitable air insulated bus bar covered by proper insulation assigned for indoor installation equipped with vacuum type circuit breaker. The switchgear shall be provided with suitable interlocks and adequate safety devices to prevent access to the live compartment. 33 KV and 11Kvcircuit breakers to be withdrawable type. A set of metal shutters shall be provided to cover all live parts. Shutters shall open automatically by positive drive initiated by the movement of circuit breaker carriage. The circuit breaker should be fixed with suitable fixation facility in test position during transportation of mobile substation in order to protect the plug and socket isolating devices. 8.2 CIRCUIT BREAKER OPERATING MECHANISM:- Circuit breaker operating mechanism shall be of the spring powered stored energy. Each equipment shall be provided with visual indicating device to show the circuit breaker "Open" or "closed" it shall operative when the circuit breaker is in the "service" "isolated" and "earthed" positions. (3-21)

39 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA It shall be possible to complete the closing tripping indication and interlock circuits when the circuit breaker is isolated. Locking facilities shall be provided so that the circuit breaker can be locked in each position. The closing mechanism shall be provided with electrical release coils and shall be of "trip free" type. It shall be possible to charge the mechanism spring with circuit breaker ineither the "open" or the "closed" position. In normal operation the recharging of the operating spring shall be commenced immediately and automatically upon completion of the circuit breaker closure. A visual mechanical indicating device shall be provided to indicated the state of the spring " spring charged" when the spring is in condition to close the C.B and "spring free" when the spring not in a condition to close the C.B. The mechanism shall be fitted with local manual spring release preferably by push botton, shrouded to prevent inadvertent operation. The mechanism shall be suitable for motor and hand rewinding (motor should be for a system of 220 V A.C) and shall be suitable for remote control for both closing and opening operations. 9. TRANSFORMER: 9.1 TRANSFORMER SPECIFICATION The transformer and its associated equipment shall comply with the latest issue of IEC6076. It should be as slim as possible to suit the requirement of the substation. The transformer shall have the following characteristics: a) Rated output power (ONAN) 10 MVA, 16MVA b) Duty Step Down, Outdoor service c) Type Core, double wound 3- phase, box type d) Rated voltage at no load H.V 33 kv L.V 11.5 kv e) System frequency 50 Hz f) Interface connection H.V- Delta L.V- star with neutral brought out Through 15 kv outdoor bushing and arrester of 7.3 KV g) Vector group Dyn 11 h) Type of cooling ONAN i) Temperature rise 45 C in top oil by thermometer 50 C in winding by Resistance j) Impedance voltage 7-10% at 75 C and at principal tapping k) System highest voltage H.V 36 kv L.V - 12 kv l) Terminal arrangement Suitable for switchgear connection m) Taps On- load on H.V. side for variation in equal steps from + 7.5% to 10% n) Oil characteristics To be confirmed 9.2 ON LOAD TAP CHANGER: The tap changer is to comply with IEC recommendation. Each transformer shall be equipped with on load tap changer suitable for the rated current of the transformer (+ 20 % over load) on-load tap changer of modern design and robust construction of MR type VACUTAB (machine - fabrick ReinHausen of West Germany). The current breaking contacts shall be contained in a separate oil tank. The tap changer shall be easily accessible so that it could be inspected and if necessary removed without having to remove the cover of main tank. The mechanism derive shall be (ED) type, designed to be controlled through push buttons. In addition to manual operation by means of a suitable operating handle. necessary interlock shall be provided to prevent simultaneous operation of manual and electric drive. The tap changer motor shall be designed for 3 - phase, 416 volt A.C. supply the tap changing process once initiated must be completed even in case of power failure to the driving mechanism. (4-21)

40 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA It shall not be possible for the tap changer to be left in an intermediate position. The tap changer control circuit should be provided with protective device against short circuit when the tap changer is in operation. (To prevent operation of tap changer during short circuit ). The mechanism, fuses, relays and control equipment shall be housed in a suitable weather proof metallic cabinet mounted on the transformer. 9.3 FITTINGS AND ACCESSORIES: The following fittings and accessories shall be provided: a. Conservator to be provided with filter cap and drain valve and a shut off valve between the conservator and transformer tank. b. Oil level gauges marked to indicate normal level at 20 C one at each side of the conservator one for transformer oil and the second for the tap changer oil. c. Explosion vent, double diaphragm type, with port hole type oil level gauge. With one contact for tripping. d. Dial type thermometer to indicate top oil temperature with maximum reading pointer and 2 sets of contacts suitable for alarm and trip. e. Winding temperature indicator to indicate the hottest spot temperature of the winding with maximum reading indication and two sets of contacts for alarm and trip. f. Drain valve plug g. Dehydrating breather for each part of conservator h. Buchholz relay, double float type and flap with alarm and trip contacts and test terminal block. i. Gas relay for OLTC with trip contact j. Manhole of adequate size to permit internal inspection of the transformer. k. Air release plugs on the top of the necessary transformer parts l. Two nos.. filter valves with caps. m. Rating and terminal plate to be chromium plated n. Two nos. Grounding pads. o. Lifting and jacking lugs p. Water proof metallic junction box to house all terminals, controls, etc q. Alarm and signaling relays for all control and protection equipment of the transformer. All these devices shall be mounted on the 33 kv switchgear panel or on transformer control board. 9.4 PAINTING A primary coat shall be applied immediately after cleaning all ungalvanized metallic parts thoroughly. An oil and weather resistance type second coat shall then be applied and the transformer finished in aluminum metallic paint. 9.5 INSULATING OIL The transformer shall be supplied with first filling of oil. The insulating oil shall be SHELL DIALA (B) or BP Energol JS-V/JS-A no other Oil will be acceptable 9.6 TESTING OF TRANS PORMER In addition to the routine test which shall be carried out on the power Transformer. A type test of temperature rise, and impulse withstand voltage test must be carried out on one transformer test should be carried out by KEMA or CESI or EDF of France. 9.7 LOSS EVALUATION The tolerance permitted is + 10% of the evaluated guaranteed total losses mentioned in the offer. Any transformer with losses more than + 10% will be rejected for transformers with total losses within + 5% of the evaluated guaranteed losses, no variation to the contract price shall be made. For transformers where the total evaluated losses between + 5% to + 10% of the total guaranteed losses, the contract price shall be reduced by the cost of the difference between the total evaluated costs of losses and the 105% of the total evaluated losses according to the following values:- Iron losses 1800 USD per kw. copper losses 600 per kw. (5-21)

41 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA for any transformer with total losses less than 100% of the guaranteed losses, no variation to the contract price shall be made 9.8 COMPENSATION FOR EXCESSIVE TEMP ERATURE RISE If the transformer C.M.R. output must be reduced by n% to maintain the rise of temperature of any part of the transformer within the guaranteed limits, the compensation shall represent twice times n % of the corresponding F.O.B. price of the transformer. 10. DC SUPPLY:- Two kinds of DC supply are required: - The first is the main DC supply for control and protection is to use (110 V) DC system consist of nickel - cadmium alkaline type battery set of (55) ampere - hour, and battery charger of (20) Amp Current rating, of floating operating mode able to supply the control and protection circuit load and at the same time to charge the battery. the R.M.S ripple voltage on the DC side shall be less than 1% of the mean DC voltage. On the front of the charger housing shall include the following: - Operating on/off switch with red and green lamps respectively. DC voltmeter indicating charger or battery voltage with selector switch. DC Ampere meter to indicate the total output current. the second emergency DC supply is to use a capacitor storage units instead of the main DC in case of low or failure of DC voltage of battery and battery charger set. the charging of these capacitors shall be from the auxiliary transformer through rectifier, and this supply is to feed all protection and tripping circuit of 33kv and 11kv C.B including protection circuit of transformer tripping relay DC DISTRIBTION BOARD Consist of necessary MCCB and MCB s with suitable current ratings and sufficient number to fulfill all requirement of the DC distribution. DC under voltage and earth fault relay & indicators to be provided. voltage & current meters are required. (6-21)

42 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA 11. CONNECTION The required arrangements regarding the connection between the substation with the network and transformer with the switchgear shall be as follows: KV CONNECTION The incoming connection to the 33 kv isolator shall be by a flexible single core cable with one end to be permanently connected to the incoming side of the isolator, or be connected after rewound the cable so the box to be of air insulated and easily worked. The other end to be of clamp for over head line connection operated from the ground by the telescopic insulating rod (the rod is to be part of the S/S) KV CONECTIONS : The outgoing feeders of the 11 KV switchgear shall be connected to the line as for the 33KV side TRANSFOMER CONNECTION The connection between transformer with H.T & L.T switchgear shall be single core cables. All the connection & live parts to be protected against direct touch so that the connection to the transformer on 33KV and 11KV sides shall be through plug in termination CABLES The 33&11kv cables are to be of flexible type EPR single core copper conductor and according to IEC recommendation: The 33kv cable for incoming to be sq mm cross section EPR type of 30 meter length with suitable clamps. The 11 kv cable for outgoing to be sq mm cross section EPR type of 50 meter length for each feeder. For transformer connection the cables to be sq mm XLPE TYPE ON 33KV SIDE AND sq mm XLPE type on 11kv side for 16 MVA mobile substation and Sq. mm. XLPE type for 10 MVA substation. Each cable has to be mounted on moving drum with arrangement for the connection on the side of the switchgear. the drum to be mounted on a stand fixed to the trailer with easy movable action for pulling & rewinding the cable. 12. EARTHING THE NEUTRAL POINT OF THE TRANSFORMER:- The neutral point of the 11 kv side of the transformer to be earthed through an earthing resistance of 21.1 OHM. 11KV 300 AMP rated current 30 sec-rated time. The housing of the resistance should include 11KV 400 AMPS on load isolator and 7.3 KV arrester. Detailed design specification, descriptions, catalogues, methods of mounting to be submitted with the offer which include : Anticorrosion methods for resistor plates. Temp. rise curves The effect of the mechanical stresses on the resister during faults. The resistor shall be equipped with /5 A CT and E/F relay to be provided 13. AUXILIARY SUPPLY 13.1 AUXILIARY TRANSFORMER:- An auxiliary transformer of (33/0.416) KV voltage and 50 KVA rating Oil immersed hermetically sealed to be supplied completed with all necessary fitting such as off load tap changer, pressure relief valve and mechanical oil level indicator. to be protected by 33kv switch fuse combination with suitable 33kv, 5Amp HRC fuses. The switch must be open automatically when each fuse has blown AC DISTRIBUTION BOARD Consist of necessary MCCB and MCB s with suitable current ratings of sufficient number to fulfill all requirements of the AC distribution. AC under voltage and earth fault relays and indicators to be provided. Voltage & current meters are required. (7-21)

43 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA 14. DRAWINGS AND INSTRUCTION BOOKS : 14.1 The following document shall be submitted in three copies with the tender documents, in English language. Technical literature giving full description of the trailer truck, transformer & switchgear offered with all details of the S/S and their contents. Also outlined drawings with dimensions showing the front side and top elevation of the trailer substation. Single line diagram to show the connection of all equipment of the S/S in detail Complete description of all equipments, Relays, C.Ts, P.Ts, C.Bs, transformer, batteries, battery charger etc Catalogues of the manufacturer for mobile s/s. Valid ISO 9001 certificate of the manufacturer of 33KV & 11KV C.Bs, 33KV & 11KV switch gears 33/11.5 KV power transformer Type test certificates of identical equipments. Reference list of manufacturer and exported mobile s/s. Incomplete tenders are liable to rejection 14.2 The document to be furnished by the successful tendrer in English language include five copies of the following drawing within two months from the date of the order. Schedule of the anticipated shipping dates. Installation drawings. Out lined drawings of the S/S, and single line diagram Sectional elevation of all part of S/S General arrangement and schematic diagram of all equipment One set of reproducible print (velograph ) tracing cloth etc of all approved drawings Two copies of final as built drawings for each s/s. NOTE : It must be noted that all drawings are subjected to approval before manufacturing BEFORE SHIPMENT : All instructions for maintenance, testing and commissioning of all relays and equipment s, shall be supplied. 15. PACKINGS The supplier will pack or protect the goods in the most appropriate manner. He will be responsible for any loss or damage arising from careless packing or protection unto the place of final destination After completion of the inspection and tests at the factory each item shall be packed for export shipment. All parts provided for shipping purposes only and which are to be removed at the time of erection shall be conspicuously tagged.the method of packing shall be such as to protect all of the items against excessive corrosion or dampness, and shall afford adequate protection against breakage or other injury, or loss due to breakage of cases or crates from the time leaves the factory until finally inst. allied during which time the apparatus will travel by rail, by a long sea voyage again by rail or truck to the site of the stores. The apparatus will also undoubtedly stand on wharves and in the open during and in between periods of transportation and will there be exposed to heavy rains, hot sun, humid climate and sudden changes of temperature. Owing to the numerous handling, extra ordinary care should be given to the packing of the equipment and especially the item having insulating material to prevent the injury due to moisture from sources external to the packing or from excessive condensation with the packing. 16. INSPECTION The material shall be subject to inspection and test by our inspectors at any time during manufacturing. (8-21)

44 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA The manufacture shall provide all inspection facilities for the said inspection and testing. All testing and inspection shall be made at the place of manufacture. The inspector shall have the right of rejecting any portion of the material at any time during manufacture if it does not meet with the requirements of this specification in all particulars. He shall have the right of overseeing the packing and shipping of all materials to be supplied. 17. Test at manufacturer s work. Manufactures work shall comprise type tests and routine tests, and a complete invitation ( full accommodation and traveling cost ) of four engineers for two weeks on the manufactures account for witnessing the tests. A. TYPE TEST :- These tests are in general, those detailed in the IEC standards which pertain to the equipment being tested equipment type test approve the general design of the equipment. the manufacturer may submit test certificates of tests which have been carried out on identical equipments. The inspector after referring to the COE may accept such certificate in lieu of the specified type test or to reject them. The type test prescribed shall be carried out in all cases where such certificates are not available or are rejected. The type test shall be carried out according to the IEC standards. certified test certificates issued by KEMA or any other qualified laboratory after agreement with the purchaser for type tests carried out on identical equipment will be accepted in lieu. B. routine test : The routine test shall be carried out on all equipment according to latest IEC standards :- 18. guarantee:- The tender shall confirm that mobile substations against defects arising from faults in design, materials and workmanship, for a period of (12) months from commissioning or (18) months from delivery whichever period expires earlier. 19. spare parts:- The tenderers are requested to give spare list sufficient for five years operation with unit price for each item, and also see spare parts list. to submit unit price per piece and per set ( if necessary). Itemized prices for recommended spare parts indicated in a list attached. 20. technical specification :- The required technical specification of the main equipment s are listed in tables. the tenderer is required to fill tables fully. any values are site rating values. (9-21)

45 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA SCHEDULE "A" SCHEDULE OF GUARANTEED PERFORMANCE AND OTHER TECHNICAL PARTICULARS The schedule is to be fully completed by the tenderer to provide detailed characteristics of the equipment and materials offered, which shall be guaranteed. This is an important point which shall be taken into consideration during tender analysis. TRANSFORMERS: # Description Unit Specification offered 1 Name of manufacturer 2 Country of origin 3 Standard on which performance data is based 4 Continuous maximum rating for the specified temperature rise and ambient temperature ( vide class 5(1)-(KVA) a. ONAN rating 5 Rated temperature rise a- Oil by thermometer C b- Winding by resistance C 6 Hottest spot temperature 7 No-load voltage ratio at normal tap 8 Exciting current referred to H.V.50 HZ Amp. a- 90% rated voltage b- 100% rated voltage c- 110% rated voltage 9 Power factor of exciting current at 100% rated voltage and 50 Hz 10 Iron losses at 50 Hz and at kw a- 90% rated voltage b- 100% rated voltage c- 110 % rated voltage 11 Cupper losses at full load (ONAN) rating at 75 C Kw 12 Total losses Kw 13 Resistance voltage at full load and at 75º C % 14 Reactance voltage of full load and at 75º C % 15 Impedance voltage at full load and at 75 ºC % a- At normal tap b- At highest tap c- At lowest tap 16 Resistance of H.V. winding per phases at 20ºC Ohm 17 Resistance of L.V winding per phase at 20º C Ohm 18 Regulation at full load 75º C a- 1.0 power factor b- 0.8 P.F lagging 19 Efficiency at 75º C % a- 100% load b- 75% c- 50% d- 25% 20 Calculated thermal time constant (ONAN) Hrs 21 Maximum flux density at normal voltage and (KI/ eq.cm) frequency and at normal ratio a- Core b- Yoke 22 Maximum flux density at 110% voltage and (KI/ eq.cm) (10-21)

46 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA # Description Unit Specification offered Frequency and at normal ratio a- Core b- Yoke 23 Insulation of a- core bolts b- core bolts washers c- side plates d- core laminations 24 Current density in windings A/cm 2 a- H.V. winding b- L.V. winding 25 Insulation on copper 26 Insulation strength of winding H.V L.V KV H.V L.V a- Impulse full wave b- Impulse chopped wav c- Applied voltage test d- Induced voltage test kv 27 Insulation strength of terminals 33kV 11kV a- over voltage test b- Minimum impulse withstand voltage c- Minimum impulse withstand voltage d- Minimum puncture or oil-immersed withstand voltage 28 Type of core 29 Tap changer a- manufacturer b- type c- time required for one tap change d- no. of steps e- Step of one tap in percent of rated voltage % 30 Dimensions of tap-changer control panel cm 31 Thickness of transformer tank mm a- sides b- bottom 32 Weights and dimensions Kg H.V L.V a- Net weight of core b-net weight of copper c- Net untanking weight of core, frame and coil d- Volume of insulating oil (Imp-gall) e- Net weight of insulating oil f- Total weight of transformer less oil Tons g- Weight of the largest shipping package Tons h- Crane lift for untanking core and coils M i- Crane life for removal of bushings M j- Dimensions of transformer M I- Under base to tap most point II- Under base to bushing mounting flange III- Overall breadth IV- Overall length k- Overall shipping dimensions of the largest package 33 Noise level at a distance of 3 meters db (11-21)

47 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA TECHNICAL SPECIFICATION FOR INDOOR CIRCUIT BREAKER # Description Unit specification offered 11kV 33kV 1 Make 2 Type 3 Normal rated voltage V 4 Normal current rating A 5 Breaking capacity a-symmetrical KA(r.m.s) b- symmetrical MVA b-asymmetrical KA(r.m.s) 6 Making capacity KA peak 7 Rated short time current 1 sec 8 Capacitive breaking current A 9 Capacitive making current A 10 Certification for the above capacities a- Name of certifying authority b- Number of certificates issued by the Authority a copy of which is enclosed with the tender 11 Impulse voltage withstand 1.2/50 wave K.V crest 12 Standard 1 min.50 Hz withstand K.V(r.m.s) voltage 13 temperature rise of main contacts continuous operation at rated current 14 Opening time a- Without current msec b- At 100% breaking current msec 15 Total break time msec 16 Making time msec 17 Type of closing mechanism 18 Power at normal voltage for shunt trip w coils 19 Minimum clearance in air a- between phases mm b- between live part & earth mm 20 weight of complete circuit breaker kg (12-21)

48 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA TECHNICAL SPECIFICATION OF CURRENT TRANSFORMERS # Description Unit 1 make 2 Impulse voltage withstand (1.2/50 wave) KV(peak) 3 I min.power frequency withstand voltage KV.(r.m.s) 4 Rated short time current (3 sec) K.A(r.m.s) 5 Temperature rise of windings on C continuous operation at rated current & output 6 For feeder circuit: a- Type b- Accuracy class c- Transformation ratio d- Current ratio error % e- Phase displacement min 7 For transformer circuit: a. Over current & instrument 1- Type 2- Accuracy class 3- Transformation ratio 4-Current ratio error 5-Phase displacement b. Differential 1- Type 2- Accuracy class 3- Transformation ratio 4- Correction C.T. ratio 5-Current ratio error 6-Phase displacement 8 For metering transformer circuit 1- Type 2- Accuracy class 3- Transformation ratio 4-Current ratio error 5-Phase displacement 9 For metering Auxiliary Transformer circuit 1- Type 2- Accuracy class 3- Transformation ratio 4-Current ratio error 5-Phase displacement specification offered 11kV 33kV (13-21)

49 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA TECHNICAL SPECIFICATION OF THE VOLTAGE TRANSFORMER # Description Unit specification offered 11kV 33kV 1 make 2 type 3 rated output VA 4 Rated frequency Hz 5 Number of phases (3 phase/single phase) 6 Transformer ratio 7 Accuracy class 8 Ratio error % 9 Phase displacement min 10 Temperature rise limit at rated primary C voltage 11 Rated voltage factor (1,9 for 8 hrs ) 12 Fuse protection a- Rated primary side A b- Rated secondary side A 13 Insulation level A a- Impulse withstand voltage KV(peak) b- I min. power frequency withstand KV(r.m.s) voltage 14 Dimensions a- Length mm b- Width mm c- Heigh mm TECHNICAL SPECIFICATION FOR THE SWITCHGEAR # Description Unit specification offered 11kV 33kV 1 make 2 type 3 Bus Bar a- Normal current rating A b- Temperature rise on continuous operation C at normal current c- Cross sectional area mm 2 d- Insulation of Bus Bar e- Maximum working temperature of busbar C insulation f- Bus bar joints insulation g-- Minimum clearance between phases mm h- Minimum clearance between phases & kv earth 4 Service voltage kv 5 Highest voltage kv 6 Impulse withstand voltage K.V(peak) 7 1 Min. power frequency withstand voltage K.V(r.m.s) 8 Dimension a- length mm b- width mm c- height mm (14-21)

50 Technical Specification of 33/11 kv Mobile Sub-Station for 1 10 & 1 16 MVA SCHEDULE (B) OIL CHARACTERISTICS TABLE (TO BE COMPLETED BY THE TENDERER) # DESCRIPTION UNIT SPECIFICATION 1. MAKERS NAME 2. REFERENCE NAME OF OIL 3. SLUDGE VALUE % 4. FLASH POINT (CLOSED) C 5. POUR POINT C 6. VISCOSITY AT 21 C CST 7. ELECTRIC STRENGTH (BREAK DOWN KV VOLTAGE) 8. ACIDITY (NEUTRALIZATION VALUE) MG/ KOH/G - TOTAL - INORGANIC 9. SAPONIFICATION VALUE MG/ KOH/G 10. COPPER DISCELERATION 11. CRACKLE 12. SPECIFIC GRAVITY 13. SULFER CONTENT 14. DIELECTRIC DISSIPATION FACTOR (15-21)