22 kv OUT DOOR VACUUM CIRCUIT BREAKER

Transcription

1 GUJARAT ENERGY TRANSMISSION CORPORATION LTD. SARADAR PATEL VIDYUT BHAVAN, RACE COURSE, BARODA TECHNICAL SPECIFICATION FOR 22 kv OUT DOOR VACUUM CIRCUIT BREAKER Getco/Engg/TechSpec/22kV/O/D VCB/R1/Nov07

2 SPECIAL INSTRUCTIONS TO BIDDER Please read following instructions carefully before submitting your bid. 1. All the drawings, i.e. elevation, side view, plan, cross sectional view etc., in AutoCAD format and manuals in PDF format, for offered item shall be submitted. Also the hard copies as per specification shall be submitted. 2. The bidder shall submit Quality Assurance Plan with the technical bid. 3. The bidder shall have to submit all the required type test reports for the offered item. In absence of this, the evaluation shall be carried out accordingly as non-submission of type test reports. 4. The bidder must fill up all the points of GTP for offered item/s. Instead of indicating refer drawing, or as per IS/IEC, the exact value/s must be filled in. 5. All the points other than GTP, which are asked to confirm in technical specifications must be submitted separately with the bid. 6. The bidder is required to impart training in view of manufacture, assembly, erection, operation and maintenance for offered item, at his works, to the person/s identified by GETCO, in the event of an order, free of cost. The cost of logistics will be bear by GETCO. 7. Please note that the evaluation will be carried out on the strength of content of bid only. No further correspondence will be made. 8. The bidder shall bring out all the technical deviation/s only at the specified annexure.

3 QUALIFYING REQUIREMENT DATA (For Supply) Bidder to satisfy all the following requirements. 1) The bidder shall be Original Equipment Manufacturer (OEM). The offered equipment have to be designed, manufactured and tested as per relevant IS/IEC with latest amendments. 2) The minimum requirement of manufacturing capacity of offered type, size and rating of equipment shall be FIVE times tender/ bid quantity. The bidder should indicate manufacturing capacity by submitting latest updated certificate of a Chartered Engineer (CE). 3) Equipment proposed shall be of similar or higher rating and in service for a minimum period of THREE (3) years and satisfactory performance certificate in respect of this is to be available and submitted. 4) The bidder should clearly indicate the quantity and Single Value Contract executed during last FIVE (5) years, for the offered equipment. Bidder should have executed one single contract during last five years for the quantity equivalent to tender / bid. The details are to be submitted in following format, Sr. No ITEMS SUPP LIED TO ORDER REFEREN CE No. & DATE ITEMS QUANTI TY ORDER FULLY EXECUTED. YES/NO STATUS, IF ORDER UNDER EXECUTION REMAR K e) Equipment offered shall have Type Test Certificates from accredited laboratory (accredited based on ISO/IEC Guide 25 / or EN by the National accredition body of the country where laboratory is located), as per IEC / IS / technical specification. The type test reports shall not be older than FIVE years and shall be valid up to expiry of validity of offer.

4 SECTION I GENERAL TECHNICAL REQUIREMENTS FOR 22 KV OUT DOOR VACUUM CIRCUIT BREAKER 1.1 SCOPE This section covers the design, manufacture, testing, inspection, supply and delivery of 22 KV Out door Circuit Breakers with associated accessories and complete in all respects specified in the schedule of requirements. 1.2 APPLICABLE STANDARDS Except where specified otherwise in this specification, the circuit breakers shall conform to the requirements of the latest edition of IS /IEC 56. However, in the event the offered breakers confirming to any other standard, salient points of differences between the standard adopted and the standards specified shall be clearly indicated in the offer. 1.3 DRAWINGS As a part of the proposal, the bidder shall furnish the drawings in triplicate incorporating the following particulars for the purpose of preliminary studies. a) Drawing showing the general outline dimensions of circuit breakers, with clear identification of parts / items. b) Drawing showing control cabinets and circuit diagrams for operating mechanism of circuit breakers. c) Compression type terminal connectors for the breakers Within 15 days of receipt of a purchase order, the bidder shall furnish to the purchaser following drawings for the approval of the purchaser.

5 a) Outline dimensional drawings showing all parts / items, transport weight etc. of circuit breaker & its support structure. b) Sectional views showing the general constructional features, Operating mechanism, and extinguishing chambers etc. of circuit breakers. c) Detailed drawings of operating mechanism of circuit breakers. d) Wiring and control diagram. e) Drawings of foundation details, mounting structures, spacing of bolts etc. f) Compression type terminal connectors suitable for (ACSR) panther conductor, with STC rating & bill of material & complete dimensions The bidder may also, submit any other drawings found necessary in addition to the drawings stated above GENERAL DESIGN FEATURES OF CIRCUIT BREAKERS The circuit breaker shall be VCB type. The breakers shall be offered as a complete unit with all piping equipment in place and all internal wiring installed and terminated in the mechanism housing and breaker shall be compete in all respect The circuit breakers shall be capable of rapid and smooth interruption of currents under all conditions completely suppressing all undesirable phenomena even under the most severe and persistent short circuit conditions or when interrupting small currents or leading or lagging reactive currents. The circuit breakers shall be Restrike-Free under all operating conditions. The details of any device incorporated to limit or control the rate of rise of restriking voltage across, the circuit breaker contacts shall be stated. The over voltages caused by circuit breaker while switching inductive or capacitive loads shall not exceed 2.5 times the highest phase to neutral voltage. The actual make and break times

6 for the circuit breakers throughout the ranges of their operating duties shall be stated in the offer and guaranteed The arc quenching chambers shall have devices to ensure almost uniform distribution of voltage across the interrupters Breaking Capacity - The interrupting capacity of the breaker for kilometric faults (short line faults) shall be equal to its interrupting capacity [as per Clause of IS 13118] and shall be stated in the offer. The details of tests conducted for confirming the capability of the breakers under kilometric fault conditions shall be furnished in the offer The circuit breakers shall be designed for interrupting line charging currents without undue rise in the voltage on supply side and without any restrike and without showing signs of undue strain. The guaranteed over voltage which shall not be exceeded while interrupting the line charging currents as specified under the Clause 2.4.(10) Section-II of this specification shall be stated in the offer The circuit breakers shall be capable of interrupting small inductive currents (occurring while switching off unloaded transformer) without giving rise to undue over voltage and without restrikes. The maximum over voltage value which will not be exceeded under such conditions shall be stated in the offer, In case of requirement type test for small inductive current interrupting capacity shall be arranged as per provision of IEC 56 or IS Restriking Voltage - The circuit breakers shall be capable of interrupting the rated power when the restriking voltage has a frequency of not less than 400 Hz and with a restriking voltage having frequency of 2000 Hz. The circuit breakers shall be capable of interrupting atleast 50% of nominal breaking capacity.

7 The measures adopted for ensuring proper operation at high rate of rise of restriking voltage and for limiting the actual voltage values across the breaks shall be described in the offer. The type characteristics and rating of the resistor used, if any, to shunt the breaker contacts and of the auxiliary switching devices used for interrupting the resistor current shall be clearly stated Recovery voltage and power Factor The circuit breaker shall be capable of interrupting the rated power with recovery voltage equal to the rated maximum line to line service voltage at rated frequency and at a power factor not exceeding The circuit breakers shall also be capable of satisfactory operation even under conditions of phase opposition that may arise due to faulty synchronising. The maximum power which the breaker can satisfactorily interrupt under phase opposition shall be stated in the offer The operating duty of the circuit breaker shall be as specified under Clause (11) section II of specific technical requirement for breakers Temperature Rise The temperature rise and the maximum temperature on any part of the equipments when in service under continuous full load conditions and exposed continuously to the direct sun-rays shall not exceed the permissible limits as per relevant ISS. When the standard specifies the limits of temperature rise, this shall not be exceeded when corrected for the difference between ambient temperature at site and the ambient temperature specified in the relevant specification. The correction proposed shall be stated in offer and shall be subject to the approval of the purchaser General Features of Circuit Breakers The circuit breakers shall be suitable for outdoor operation under the climatic conditions specified in section-ii of this specification.

8 Exposed live parts shall be placed high enough above ground to meet the requirements of local safety codes All similar parts, particularly removable one and shall be interchangeable with one another VCB shall consist of three identical single phase units with common operating mechanism suitable for specified duty. Bidder may give complete constructional details for VCB offered by them. The insulation level of porcelain of the circuit breaker shall be so cocoordinated with that of the equipment that flashover shall occur externally to the equipment Insulation of the Circuit Breaker - The insulation to ground, the insulation between open contacts and the insulation between phases of the completely assembled circuit breaker shall capable of withstanding satisfactorily die-electric test voltages corresponding to BIL specified in Clause SECTION II of this specification i.e. Lightening impulse with stand voltage shall be150 KVP & One minute P.F. withstand voltage shall be 55 KV rms Adequate clearance shall be provided between phase and from phase to ground. The clearance shall be such that the breaker shall withstand the BIL specified under clause no of this specification. The minimum clearance from live parts to ground level shall however be subject to the purchaser s approval Contacts of Circuit Breaker The main contacts shall have adequate area and contact pressure for carrying the rated currents and the short time rated breaking currents of the breaker without excessive temperature rise. Contacts shall have a minimum of movable parts and adjustments. The main contacts shall be first to open and last to close so that burning and wearing of the contact may be negligible. Main contacts shall be of copper. Moving contacts shall have permanent marking or scale. Identification shall be invariably

9 and legibly marked on VCB mechanism so that the extent of wear and tear can be measured. Necessary instruction there of shall be furnished on front of panel Operating Mechanism of Circuit Breakers Circuit breakers shall be power operated either by pneumatic mechanism or by a motor compressed spring charging mechanism depending on the type of breaker offered. The mechanism will be trip-free electrically and mechanically. The mechanism shall be strong, quick in action and shall be removable without disturbing other parts of the circuit breakers. All the working parts in the mechanism shall be of corrosion resistant materials and all bearings which require greasing, shall be equipped with pressure grease fittings. The mechanism and breaker shall be such that the failure of any spring will not prevent tripping and will not cause tripping or closing The circuit breakers shall be designed for remote control from the control room and there shall be provision for manual operation of circuit breakers during maintenance and for local tripping and closing by normal means The circuit breaker shall have a mechanical ON-OFF indicator in addition to facilities for remote electrical indicator The operating mechanism along with its accessories shall be mounted in a weather proof cabinet with hinged doors located near the breakers.. The local control switch and the breaker position indicator shall be provided in this cabinet. The control circuit shall be designed to operate on 110 V.D.C. as specified in section-ii of this specification. The closing and opening coils shall be designed to operate satisfactorily at any control voltage from 80% to 115% of the normal voltage. A heater of adequate capacity with thermostat shall be provided in the cabinet to avoid moisture condensation.

10 (a) The terminal block shall of 1.1 KV voltage grade & shall be with stud type connections instead of with screw types connections Auxiliary switches- A minimum number of 6 NC + 6 NO Auxiliary switches contacts shall be provided on each circuit breaker for use in remote indication control scheme of the circuit breakers and for safety interlocking. Special contacts for use with trip coils shall also be provided. Provision shall be made for adding more auxiliary switches, if required. Auxiliary switches shall be placed in weather proof galvanized casing and current rating of switches shall be mentioned in the bid. 1.5 BUSHING & INSULATORS The porcelain insulator used in manufacturing the bushings shall be homogeneous, free from laminations, cavities and other flaws or imperfection that might affect the mechanical or dielectric qualities. All bushings of identical ratings shall be interchangeable. The bushings shall conform to the latest edition of IS 5621 or any other equivalent standard (Latest). The puncture strengths of the bushings shall be greater than their flashover values. The bushings shall be entirely free from external and internal corona. The total minimum creepage distance of the bushings shall be suitable for heavily polluted atmosphere. 1.6 TERMINAL CONNECTORS AND EARTHING TERMINALS Nos. of Compression type terminal connectors per breaker suitable for ACSR PANTHER Conductor shall be supplied and they shall be suitable for both vertical and horizontal connections of the Transmission line conductor or station bus bar. Suitable terminal earth connectors (two Nos.) for earthing connections shall also be supplied. The drawing of this connector shall be submitted. SS bolt for connector shall be provided with two Nos. of SS nuts (including lock nut) & one SS washer. 1.7 TROPICALISATION

11 1.7.1 All control wiring, electric motors and accessories shall be protected against fungus growth and other harmful effects due to tropical environments. 1.8 GALVANISING All ferrous parts of breakers and compressed air plant including bolts, nuts etc. shall be hot-dip galvanised as per latest edition of IS PAINTING Mechanisms, enclosures, cabinets and other metal parts shall be thoroughly cleaned to remove all rust scales, corrosion and other adhering foreign matter, steel surfaces, as far as possible shall be painting with not less than two coats of heat resistant, oil insoluble, insulating varnish light-grey pains as per shade no.631 of IS5 shall be selected to withstand tropical heat and extremes of weather/heavily polluted atmosphere TEST AND TESTS REPORTS Reports of following type tests carried out in Govt. approved laboratory within five years prior to Date of Bid opening and shall be valid up to expiry of validity of offer as per IS for circuit breakers shall be submitted along with the offer (i) Lightening impulse withstand voltage test (ii) Power frequency voltage withstand voltage test. (DRY as well as wet). (iii) Temperature rise test. (iv) Measurement of resistance of main circuit (v) Short time current withstand and peak current with stand Test (vi) Mechanical endurance test (vii) Single phase short circuit test. (viii) Out of phase making and breaking current test. (ix) Capacitor current switching test for isolated neutral capacitor banks. In case of non-submission of some of the type test reports, the bidder shall confirm the submission of same before commencement of supply without affecting delivery schedule of breaker.

12 Routine tests as per the latest edition of IS for circuit breakers shall be carried out on each circuit breaker (in presence of purchaser s representative if degreed by the purchaser) The test reports for type tests and routine tests in respect of associated equipments as motors, instruments, relays etc. as per the latest edition of the relevant IS shall be supplied by the bidder All tests reports for acceptance / routine tests shall be submitted and got approved from the purchaser before dispatching the breaker SPARE PARTS The bidder shall furnish an item wise list and quantity of recommended spare parts, if any, for five years' operation of the air break Isolators, with unit price of each part ERECTION The bidder shall quote for the services of an erection engineer who shall take full responsibility for the erection, testing, and commissioning of the breakers. Skilled labour for erection work will have to be arranged for by the successful bidder. Erector shall bring all special tools and instruments required. Rates of pay, on daily and monthly basis as well as the estimated duration of execution shall be indicated The erection and commissioning of the breaker shall be supervised, if required by the purchaser, through supplier s representative who shall direct the sequence of erection and make necessary adjustments to the apparatus and correct in the field any errors or omissions on the part of the supplier in order to make the breakers and material to function in accordance with the intent of this specification The purchaser shall not be responsible for any damage to the breaker during commissioning if such damages result from faulty or inadequate erection. Purchaser shall provide local workmen as well as ordinary tools and equipments required for erection.

13 Supplier shall not be liable for any loss, damage or injury to property or persons at the installation site unless such damage or injuries are caused by any act or negligence of the supervising erector TECHNICAL & GUARANTEED PARTICULARS The bidder shall furnish all guaranteed technical particulars as called for in section-iv (Schedule- A ) of this specification. Particulars which are subject to guarantee shall be clearly stated offers not containing this information will not be considered. Deviation against any clause of this technical specification shall be clearly described in annexure 12 only INSTRUCTION MANUALS There copies of operation, maintenance and erection manuals in English language shall be supplied one month prior to the dispatch of the circuit breakers. In addition, two copies of the same per sub-station shall be supplied. The manuals shall be bound volumes and shall contain all the drawings and instructions required for erection, operation and maintenance and in addition the following particulars a) Marked erection prints identifying the component parts of the circuit breakers and current transformers as dispatched with the assembly drawings. b) Details dimensions, assembly and description of all the components and catalogues for operation of the circuit breaker and accessories. c) List of recommended spare parts of circuit breaker.

14 SECTION II TECHNICAL SPECIFICATION FOR 22 KV OUTDOOR CIRCUIT BREAKERS SPECIFIC REQUIREMENTS. 2.1 SCOPE This section covers the specific technical requirements, climatic and isocerunic conditions and system particulars for which the circuit breakers shall be offered as per the General Technical Requirements given in Section-I of this specification and the schedule of requirements specified herein for the various sub stations. 2.2 CLIMATIC & ISOCERAUNIC CONDITIONS The climatic conditions under which the breaker shall operate satisfactorily are as follows a) Maximum ambient temperature of air in shade ( 0 C). b) Minimum ambient temperature of air in shade ( 0 C). c) Maximum daily average ambient temperature ( 0 C). d) Maximum yearly average ambient temperature ( 0 C) e) Maximum relative humidity (%). 95 f) Average number of thunderstomn days / annum. 15 g) Average annual rainfall (Cm.) 150 h) Maximum wind pressure (Kg/m2) 150

15 i) Height above mean see level (m). Not exceeding 1000 meters All breakers offered shall be suitable for continuous satisfactory operation at the full rated capacity under the above climatic conditions Since the sub-station may be near seashore or Industrial area, the breaker offered shall be suitable for heavily polluted atmosphere. 2.3 SYSTEM DETAILS i) Nominal system voltage(kv) 22 ii) Maximum rated voltage (KV) 24 iii) Frequency (Hz ) 50 iv) Number of phases 3 v) Neutral Earthing Solidly earthed. vi) Auxiliary power supply 1) 240 Volts 1-φ & 415 Volts 3-φ, 50 Hz A.C., with the variation of frequency 48.5 to 51.5 and voltage +10% & -15% occasionaly. 2) 110 Volts or 220 Volts 2-wire D.C. supply subject to variations of ± 10%. The circuit breakers shall complete with following technical requirements. 11) Number of Poles 3 2) Basic Insulation level

16 1) 1.2/50 Microsecond impulse withstand voltage (KVP) ) On Minute Power Frequency withstand voltage (KV rms). 55 3) Rated normal current (Amps.) a) Rated symmetrical breaking capacity at highest system voltage. (MVA) 4) Rated short circuit breaking capacity KA (rms.) 5) Rated duration of short circuit seconds. 6) Total break time for any current upto the rated breaking current cycles ) Closing time. Not more than 10 cycles. 8) Rated characteristics for short line faults 9) Rated transient recovery voltage for terminal fault. 10) Rated line charging current breaking capacity (Amps.) 11) Rated short circuit making current KAP. As per Clause of IS 13118/IEC-56. As per Clause of IS 13118/IEC ) Rated operating duty Sec-Co-3 Min. Co.

17 13) Total creepage distance for heavily polluted atmosphere (mm ) ) Type of circuit breaker Vacuum 2.5 EARTH QUAKE & WIND DESIGN LOADS Each circuit breaker including its supporting structure shall be designed to withstand required earthquake acceleration of 0.08 x 2 g and with wind loads of 150 Kg/m2 on the projected area (non-simultaneous) without damage to component parts and without impairment of operation.

18 APPENDIX - I BIDDING SCHEDULES (TO BE FILLED IN & SIGNED BY THE BIDDER) SCHEDULE A GUARANTEED TECHNICAL PARTICULARS FOR 66KV CIRCUIT BREAKERS 1. Name of Manufacturer 2. Type Designation 3. Governing Standard 4. Rated Voltage (KV) 5. Maximum continuous rated service voltage (KV) 6. Frequency (Hz) 7. Operating duty cycle 8. Nominal current rating (Amps.) Under standard condition. (Amp) Under site condition (Amp). Derating factor, if any for site conditions. 9. Short time current rating (KA) for 3 seconds

19 10. Maximum temperature / rise over ambient temp. due to rated current in main contacts measured after breaking test. ( 0 C) 11. Rated short circuit breaking current Rated short circuit current (AC component) (KV rms). Percentage DC component Assymetrical breaking current (including DC component (KA rms). Rated symmetrical breaking capacity in MVA FOR MOCB & FOR SF6 CB 12. Making capacity (KA Peak) 13. Total breaking time (Milliseconds) a) For interruption of 10% of the rated capacity. b) For interruption of 30% of the rated capacity. c) For interruption of 60% of rated capacity. d) For interruption of the full rated capacity. 14 Arcing time ( Milli seconds ) 15. Making time (Milli seconds)

20 16. Minimum reclosing time at rated interrupting capacity from the in fault of the trip coil inrgisation (Milli-second) 17. A) Minimum dead time a) 3 phase reclosing (Milli seconds). b) Limit of adjustment of dead time for 3-phase reclosing. B) Whether restrike free and trip free. (IS/IEC applicable may be stated). 18. Rate of rise of restriking voltage for 100%, 50% & 30% rated capacity a) Amplitude factor (max) b) Phase factor (max) c) Natural Frequency (Hz) d) Rated of rise of restriking voltage (V/Micro Sec)(max) 19. Maximum interrupting capacity under phase opposition condition (MVA). 20. Maximum line charging current breaking capacity without over voltage exceeding 2.5 neutral voltage (Amps.)

21 21. Maximum line charging current breaking capacity corresponding over-voltage recorded a) On supply side. b) On line side. 22. Maximum cable charging current breaking capacity & corresponding over-voltage recorded in test. a) On supply side. b) On line side. 23. Maximum shunt capacitor Bank switching capacity (MVA) 24. Maximum breaking capacity on kilometric fault (MVA) 25. Maximum over-voltage on switching transformers on no load & the charging current. 26. Dry 1 Minute power frequency test withstand voltage, for complete circuit breaker Between line & Grounded parts (KV rms) Between line with breaker contacts open (KV rms)

22 27. Wet 1-minute power frequency withstand voltage for complete circuit breaker a) Between line terminal & grounded parts (KV rms) b) Between terminals with breaker contacts open (KV rms.) /50 Micro-second wave lightening impulse withstand test voltage for complete circuit breaker a) Between line terminal and ground (KV peak) b) Between terminal with circuit breaker contacts open (KV peak). SUPPORTING INSULATORS 29. Make & Type 30. Insulation Class 31. Visible Corona discharge voltage 32. Wet 1-minute power frequency f1ashover voltage (KV rms). 33. Dry 1-minute power frequency f1ashover voltage (KV rms) /50 micro-second impulse f1ashover voltage (in KV peak)

23 35. Total creep age distance for heavily polluted atmosphere 36. Minimum clearance in air a) Between phases (mm) b) Live parts & earth (mm) Live parts to ground level (mm). 37. No. of poles per circuit breaker 38. Breaks per pole Nos. 39. Total length of breaks per phase (mm) Type of main contacts Material of main contacts 42. Whether main contacts silver plates (Yes/No) 43. Thickness of silver coating on main contacts (mm). 44. Contact pressure on main contacts (Kg/M2). 47. Type of auxiliary switches 48. Material of switch contacts 49. Whether contacts silver plates (Yes/No.)

24 50. No. of auxiliary switch contacts operating with all three poles of breaker a) Which are closed when breaker is closed. b) Which are open when breaker is closed 51 No. of spare auxiliary switch contacts operating a) Which are closed when breaker is closed. b) Which are open when breaker is closed. 52. No. of operations possible without maintenance At full rated interrupting capacity. At 50% of rated interrupted capacity At 100% of rated current At 50% of rated current. 53. Details of foundation

25 54. Type of operating mechanism (motor operated spring charged). a) Opening b) Closing c) Control voltage aux. 55. Tripping & closing circuit voltage (V). 56. Power required for trip coil (in watts). 57. Power required for closing coil (in watts). 58. Weight of 3-φ breaker complete with operating mechanism, supporting, insulators, frame work etc. 59. Impact loading for foundation design to include dead load plug impact value on opening it maximum interrupting rating in terms of equivalent static load. 60. Weight of heaviest package (Kgs) space requirements (Length, Width, Height).

26 61. DETAILS OF VACUUM a) Quantity of vacuum per C.B. (bars) b) Standard applicable for vacuum SEAL OF THE FIRM SIGNATURE OF TENDERER Note 1) Instead of giving reference of drawing No./ IS Literature etc. actual values / figures must be furnished wherever required otherwise it will be completed to consider that the details in GTP are not furnished & technical Bid will be evaluated accordingly. 2) The tenderer should furnish the various make for bought out items wherever required in GTP instead of indicating or its equivalent.