66 Kv Circuit Breaker

GETCO/E/06TS ˘ CB 013/R2 Feb09

Page 1 of 25

GUJARAT ENERGY TRANSMISSION

CORPORATION LTD.

SARADAR PATEL VIDYUT BHAVAN, RACE COURSE, BARODA – 390 007.

TECHNICAL SPECIFICATION

FOR

66 kV SF6 CIRCUIT BREAKER (SPRING OPERATED)



Page 2 of 25

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.


Page 3 of 25

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 SUPPL

IED TO

ORDER REFERENCE No. &

DATE

ITEMS QUANTITY ORDER FULLY

EXECUTED. YES/NO

STATUS, IF ORDER UNDER

EXECUTION

REMARK

e) Equipment offered shall have Type Test Certificates from

accredited laboratory (accredited based on ISO/IEC Guide 25 / 17025 or EN 45001 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.


Page 4 of 25

TECHNICAL SPECIFICATION FOR

66 kV SF-6 CIRCUIT BREAKER

SECTION – I

GENERAL TECHNICAL REQUIREMENTS

1.1 SCOPE :

1.1.1 This section covers the design, manufacture, testing, inspection, supply and delivery of 66KV Circuit Breakers SPRING operated, along with associated accessories and complete in all respects specified in the schedule of requirements.

1.2 APPLICABLE STANDARDS:

1.2.1 Except where specified otherwise in this specification, the circuit breakers shall conform to the requirements of the latest edition of IS 13118-1991 / IEC 66-1987. However, in the event the offered breakers confirming to any other standard, salient points of differences between the standard adopted and the specified standards shall be clearly indicated in the offer.

1.3 DRAWINGS/DOCUMENTS:

1.3.1 The bidder shall furnish the drawings in triplicate incorporating the following particulars.

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) Drawing showing the complete operation cycle of the circuit breaker with description.

d) Compression type terminal connectors for the breakers. e) All the documents required shall be submitted over and above as

indicated in Section - V of the specification.

1.3.1.1 The Bidder shall submit the following drawings within 15 days from the date of receipt of clear order: -

a) Outline dimensional drawings showing all parts / items, transport weight etc. of circuit breaker & its support structure.

b) Detailed drawings of operating mechanism of circuit breakers. c) Wiring and control diagram.


Page 5 of 25

d) Drawings of foundation details, mounting structures, spacing of bolts etc.

e) Compression type terminal connectors suitable for (ACSR) panther conductor, with STC rating & bill of material & complete dimensions.

1.3.1.2 The tenderer may also, submit any other drawings found necessary in addition to the drawings stated above.

1.4.1 GENERAL DESIGN FEATURES OF CIRCUIT BREAKERS:

1.4.1.1 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 for the circuit breakers throughout the ranges of their operating duties shall be stated in the offer and guaranteed.

1.4.1.2 The arc quenching chambers shall have devices to ensure almost uniform distribution of voltage across the interrupters.

1.4.1.3 Breaking Capacity:

The interrupting capacity of the breaker for kilometric faults (short line faults) shall be equal to its interrupting capacity [as per Clause 4-106 of IS: 13118 (IEC-56)] and shall be stated in the tender. The details of tests conducted for confirming the capability of the breakers under kilometric fault conditions shall be furnished in the offer.

1.4.1.4 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 of Section-II of this specification shall be stated in the offer.

1.4.1.5 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, and in conformity to this, test reports along with oscillograph shall be furnished in the offer.


Page 6 of 25

1.4.1.6 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 at least 50% of nominal breaking capacity.

1.4.1.7 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 tender. 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.

1.4.1.8 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 0.15.

1.4.1.9 The circuit breakers shall also be capable of satisfactory operation even under conditions of phase opposition that may arise due to faulty synchronizing. The maximum power which the breaker can satisfactorily interrupt under phase opposition shall be stated in the offer.

1.4.1.10 The operating duty of the circuit breaker shall be as specified under Clause - 2.4.12 of specific technical requirement for breakers.

1.4.2 Temperature Rise:

1.4.2.1 The temperature rise and the maximum temperature on any part of the breaker 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.

1.4.3 General Features of Circuit Breakers:


Page 7 of 25

1.4.3.1 The circuit breakers shall be suitable for outdoor operation under the climatic conditions specified in section-II of this specification.

1.4.3.1(a) The circuit breakers operating mechanism shall have two nos. of tripping coils and one no. of closing coil for both 66KV SF6 Gas CB for better reliability.

1.4.3.2 Exposed live parts shall be placed high enough above ground to meet the requirements of local safety codes.

1.4.3.3 All similar parts, particularly removable one and shall be interchangeable with one another.

1.4.4 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 – 2.4.2 of this specification.

1.4.5(a) The minimum clearances in open air shall be as under in case of SF-6 Breakers:

Minimum clearance between phase : As per relevant IS.

Minimum clearance between live parts : As per relevant IS. And grounded objects.

1.4.5(b) Adequate clearance in air shall be provided between phase and from phase to ground. The clearance shall be such that the breaker shall withstand the BIL specified in the specification. The minimum clearance from live parts to ground level shall not be less than 4000 mm – including plinth height as 150 mm.

1.4.6 Contacts of Circuit Breaker:

1.4.6.1 The main contacts shall have adequate area and contact pressure for carrying the rated currants and the short time rated breaking currents of the breaker without excessive temperature rise. Contacts shall be easily replaceable and shall have a minimum of movable parts and adjustments. The main contacts shall be first to open and last to close so that burning of the contact may be negligible.

1.4.7 Operating Mechanism of Circuit Breakers:

1.4.7.1 Circuit breakers shall be power operated by a motor compressed spring charging mechanism; the mechanism will be trip-free


Page 8 of 25

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.

1.4.7.2 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.

1.4.7.3 The circuit breaker shall have a mechanical ‘ON-OFF’ indicator in addition to facilities for remote electrical indicator.

1.4.7.4 The operating mechanism along with its accessories shall be suitable for electrical operation from ground and shall be mounted in a weather proof cabinet with hinged doors located near the breakers. The cabinet shall be suitable for IP 55 degree of protection. The local control switch and the breaker position indicator shall be provided in this cabinet, which shall be free standing and supported by suitable arrangement. The control circuit shall be designed to operate on 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.

1.4.7.4(a) The terminal block shall of 1.1 KV voltage grade & shall be with stud type connections instead of with screw types connections.

1.4.8 Auxiliary switches:

1.4.8.1 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 circular breakers and for safety interlocking. Special contacts for use with trip coils and auto reclosing operation shall also be provided. Provision shall be made for adding more auxiliary switches, if required. Auxiliary switches shall be placed in weatherproof galvanized casing and current rating of switches shall be mentioned in the offer.

1.5 BUSHING & INSULATORS:

1.5.1 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


Page 9 of 25

insulators shall conform to the latest edition of IS: 3447. 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 protected and total creepage distance of the bushings shall be suitable for heavily polluted atmosphere. The creep age distance of the insulator shall be 1810mm suitable for heaving polluted atmosphere. The compressive and cantilever strength shall conform to the relevant IS.

1.6 TERMINAL CONNECTORS AND EARTHING TERMINALS :

1.6.1 Compression joint type terminal connectors 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:

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 GALVANIZING:

1.8.1 All ferrous parts of breakers and bolts, nuts etc. shall be hot-dip galvanized as per latest edition of IS: 2629. Support structure’s galvanizing shall be done as per IS 4843 (latest edition). Electro galvanized bolts nuts, & washers are also acceptable.

1.9 PAINTING:

1.9.1 Interior and exteriors of tanks, mechanisms, enclosures, cabinets and other metal parts shall be thoroughly cleaned to remove all rust scales, corrosion and other adhering foreign matter, steel surfaces in contacts with insulation oil, 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 IS:5 shall be selected to withstand tropical heat and extremes of weather.

1.10 TEST AND TEST REPORTS:


Page 10 of 25

1.10.1 Reports of following type tests carried out in Govt. approved laboratory within seven years prior to Date of Bid open as per IS: 13118 for circuit breakers shall be submitted alongwith 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. IMPORTANT NOTE: 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, from NABL accredited laboratory, free of cost. In absence of this confirmation, the offer will be evaluated as non submission of type test report.

1.10.2 Routine tests as per the latest edition of IS: 13118 for circuit breakers shall be carried out on each circuit breaker (in presence of purchaser’s representative if agreed by the purchaser).

1.10.3 The test reports for type tests and routine tests in respect of associated breakers such as spring charging motors, instruments, pressure switches, relays, terminal connectors, etc. as per the latest edition of the relevant IS shall be supplied by the bidder. All the routine test reports for all the breakers and for all the insulators utilized shall be submitted with inspection report.

1.10.4 All tests reports for acceptance / routine tests shall be submitted in spiral bound volume and got approved from the purchaser before dispatching the breaker.

1.11 SPARE PARTS:

1.11.1 Bidder shall submit list of spares recommended by him for satisfactory operation of the circuit breakers for first five years and rate for each spare shall also be quoted. The purchaser will decide the actual quantity of spare parts to be ordered on the basis of the prices of the spare parts, quoted by the bidder.

1.12 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.


Page 11 of 25

Deviation against any clause of this technical specification shall be clearly described separately.

1.13 INSTRUCTION MANUALS:

1.13.1 Three 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.


Page 12 of 25



SECTION – II

TECHNICAL REQUIREMENTS FOR 66KV CIRCUIT BREAKERS

(FOR SF-6 BREAKERS)

2.1 SCOPE:

This section covers the specific technical requirements, climatic and Isoceraunic 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.

2.2 CLIMATIC & ISOCERAUNIC CONDITIONS:

2.2.1 The climatic conditions under which the breaker shall operate satisfactorily are as follows:

a) Maximum ambient temperature of air in shade (0C).

: 500 C

b) Minimum ambient temperature of air in shade (0C).

: 40 C

c) Maximum daily average ambient temperature (0C).

: 400 C

d) Maximum yearly average ambient temperature (0C).

: 300 C

e) Maximum relative humidity (%). : 95 %

f) Average number of thunderstorm days / annum.

: 15

g) Average annual rainfall (Cm.) : 150 cm.

h) Maximum wind pressure (Kg/m2) : 150 kg/M2.

i) Height above mean see level (m). : Not exceeding 1000 meters.


Page 13 of 25

2.2.2 All breakers offered shall be suitable for continuous satisfactory operation at the full rated capacity under the above climatic conditions.

2.2.3 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 : 66 kV

ii) Maximum rated voltage : 72.5 kV

iii) Frequency : 50 Cycle / Second.

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

± 5% and voltage + 10% & -15%.

2) 110 Volts or 220 Volts 2-wire D.C. supply subject

to variations of ± 10%.

2.4 The circuit breakers shall be complete with following technical

requirements. :

11) Number of Poles : 3

2) Basic Insulation level

1) 1.2/50 Microsecond impulse withstand voltage.

2) On Minute Power Frequency withstand voltage.

:

:

350 kVp

140 kV rms

3) Rated normal current : 1600 Amps.

3a) Rated symmetrical breaking capacity at highest system voltage.

: 3000 MVA For SF6 CB


Page 14 of 25

4) Rated short circuit breaking capacity.

: 25 kA rms

5) Rated duration of short circuit : 3 second.

6) Total break time for any current upto the rated breaking current.

: 3 cycles

7) Closing time. : Not more than 10 cycles.

8) Rated characteristics for short line faults

: As per Clause 4.105 of IS: 13118 / IEC-56.

9) Rated transient recovery voltage for terminal fault.

: As per Clause-4. 102 of IS: 13118 / IEC56.

10) Rated line charging current breaking capacity.

: 10 Amps.

11) Rated short circuit making current.

: 50 KAP

12) Rated operating duty : O–0.3 S–CO–3 M–CO

13) Rated SF6 Gas pressure (AT 200C).

: 5 kg / Cm2

14) Total creepage distance for heavily polluted atmosphere.

: 1810 mm

15) Live part to plinth level clearance in mm

: 4000 mm

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.


Page 15 of 25



SECTION – III

GENERAL DESIGN OF 66KV SF6 GAS CIRCUIT BREAKER

3.2 GENERAL DESIGN FEATURE OF SF6 BREAKER:

3.2.1 SF6 GAS Circuit breaker shall consist of three identical single phase units with common Spring operating mechanism suitable for specified duty. Separate SF6 Gas Cylinder along with suitable gas system, incorporating required gas stop valves, copper piping of suitable size shall be provided. Required pressure switches as stated in Cl. 1.2.4 shall be provided. Gas pressure gauge shall be fitted on the common feed pipe to monitor the pressure of SF6 gas in the interrupter.

Absorbent shall, also, be provided in each interrupting unit to keep the SF6 gas dry & absorb the decomposed product of SF6 gas, formed during arcing.

Bidder may give complete constructional details for SF6 gas circuit breaker offered by them. The insulation level of porcelain of the circuit breaker shall be so coordinated with that of the breaker that flashover shall occur externally to the breaker.

3.2.2 In case of SF6 circuit breaker, it shall be possible to arrange for either automatic tripping of the circuit breaker or tripping of circuit breaker on fault and will be automatically locked when the pressure in the individual interrupter reaches below the limit value. Arrangements shall be made to prevent closing of the breaker due to leakage of gas passing through the closing valve without a positive impulse from the closing coil.

3.2.3 The SF6 gas used in the circuit Breaker shall comply in all respect with the provisions of the latest edition of relevant standard.

3.2.4 Inter Locks :


Page 16 of 25

3.2.4(a) Pressure switches with the required pressure fitting must be incorporated to ensure safety of breaker operation when SF6 gas pressure goes below the specified pressure range due to leakage, the trip coil circuit & closing coil circuit must be cut-off. The pressure switch shall generally be temperature compensated gas pressure switch having two micro-switches, operating at different pressures one for low pressure alarm and other for low pressure cutout.


Page 17 of 25

SECTION – IV SCHEDULE ‘A’

SCHEDULE OF GUARANTEED TECHNICAL PARTICULARS

FOR 66KV SF-6 GAS Spring operated CIRCUIT BREAKERS

(TO BE FILLED IN & SIGNED BY THE BIDDER)

SN PARTICULARS

1. Name of Manufacturer :

2.

2.a

Type Designation of CB

Type designation of Spring mechanism (as per Mech. Endu. test report)

:

:

3. Governing Standard :

4. Rated Voltage (KV) :

5. Maximum continuous rated service voltage (KV)

:

6. Frequency (Hz) :

7. Whether outdoor breaker offered (Yes / No)

:

8. Nominal current rating

i) Under standard condition. (Amp)

ii) Under site condition (Amp).

iii) Type test reports submitted of (Amp)

:

:

:

9. Short time current rating (kA) for 3 seconds

:

10. Maximum temperature rise over ambient temp. due to rated current in main contacts measured after breaking test. (0C)

:


Page 18 of 25

SN PARTICULARS

11. Rated short circuit breaking current

a) Rated short circuit current (AC component) (KV rms).

b) Percentage DC component

c) Asymmetrical breaking current (including DC component (KA rms).

d) Rated symmetrical breaking capacity in MVA FOR SF6 CB

:

:

:

:

12. Making capacity (kA Peak) :

13. Total breaking time (Milli-seconds) :

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) :

16. Minimum reclosing time at rated

interrupting capacity from the in fault of

the trip coil energisation (Milli-second)

:


Page 19 of 25

SN PARTICULARS

17. A) Minimum dead time

a) 3 phase reclosing (Mili 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. Date on restriking voltage for 100%, 50% & 30% rated capacity

a) Amplitude factor (max)

b) Phase factor (max)

c) Natural Frequency (Hz)

d) Rate 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 2.5phase neutral voltage (Amps.)

:

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)

:


Page 20 of 25

SN PARTICULARS

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

a) Between line & Grounded parts (kV rms)

b) Between line with breaker contacts open (kV rms)

:

:

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)

:

:

:

28. 1.2/50 Micro-second wave lightning impulse withstand test voltage for complete circuit breaker, as per type test report submitted.

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).

:


Page 21 of 25

SN PARTICULARS

33. Dry 1-minute power frequency f1ashover voltage (kV rms)

:

34. 1.2/50 micro-second impulse f1ashover voltage (kV peak)

:

35. Total creepage distance for heavily polluted atmosphere

:

36. Minimum clearance in air

a) Between phases (mm)

b) Live parts & earth (mm)

c) Live parts to Plinth level (mm).

:

:

:

:

36.a

b

Permissible safe cantilever loading on installed porcelain (Kg.m) Permissible safe compressive strength of installed porcelain

37. No. of poles per circuit breaker

:

38. Breaks per pole (Nos). :

39. Total length of breaks per phase (mm).

:

40 Type of main contacts :

41. 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).

:

45. Type of arcing contacts :

46. Contact pressure on arcing contact (Kg/M2).

:

47. Type of auxiliary switches :


Page 22 of 25

SN PARTICULARS

48. Material of switch contacts :

49. Whether contacts silver plates (Yes/No.)

:

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

:

:

51A No. of spare auxiliary switch contacts operating

a) Which are closed when breaker is closed.

b) Which are open when breaker is closed.

:

B Details of SF6 Gas pressure switch and its setting for low pressure alarm and low pressure cut-out.

:

52. No. of operations possible without maintenance

a) At full rated interrupting capacity.

b) At 50% of rated interrupted capacity

c) At 100% of rated current

d) At 50% of rated current

:

:

:

:

:

53. Details of foundation :


Page 23 of 25

SN PARTICULARS

54. Type of operating mechanism (motor operated spring charged).

a) Opening

b) Closing

c) Control voltage aux.

:

:

:

:

55. Tripping & closing circuit voltage (V). (110 V/220 V.)

As per requirement.

:

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).

:

61. A) Details of Gas pressure switch and its setting for low pressure alarm and low pressure cut-out.

:

:


Page 24 of 25

SN PARTICULARS

62 SF6 GAS DETAILS:

a) Rated SF6 Gas pressure (temperature 200C) (Kg/cm2)

b) IS / Equivalent standard applicable for SF6 Gas.

:

:

:

63 Terminal connector

(Bimetallic compression type)

__________________ _________________________ SEAL OF THE FIRM SIGNATURE OF TENDERER


Page 25 of 25

SECTION – V List of documents attached with technical bid: Bidder shall invariably attach the following documents and clearly marked and duly flagged in technical bid. In absence of these documents offer will be evaluated as a non submission.

Sr. No.

Particulars of document Whether attached the with technical bid

1 Drawings in AutoCAD format 2 Drawings hard copies as indicated in

specification

3 Manual in PDF format 4 QAP for manufacturing process in SOFT

format

5 QAP for manufacturing process in Hard format 6 FQP in SOFT format 7 FQP in Hard copy 8 Type test Reports in hard copies

a for breaker b for clamps & connectors

9 Confirmation regarding type tests as per clause no. 1.10(a) page no. 10 – “IMPORTANT NOTE”

10 Guaranteed Technical Particulars, completely filled in

11 Any other essential documents SIGNATURE OF BIDDER COMPANY’S ROUND SEAL DATE: PLACE:

66 Kv Circuit Breaker

Documents

heavily polluted

total creepage

low pressure

parts items

low pressure

full rated

type test

complete circuit