33kV Outdoor Switchyard Specification

1.0.0.

SCOPE:

1.0.1 The Specification covers technical requirements of 33 KV switchyard for M/s Company India limited. For their project Company chocolate plant at Place

1.2.0 The scope shall comprise but not limited to the design, engineering., manufacture, testing and inspection at manufacture’s works, packing, supply, transportation, insurance, delivery to site, unloading and handling at site, storage and preservation at site store, transportation to place of installations, complete work of site assembly, erection, testing at site and commissioning of 33 kV Air Insulated switchgears (Switchyard) and equipment erection including associated civil and structural works for Switchyard.

1.3.0 Any other equipment not explicitly mentioned herein or in the Technical specifications and drawings but are necessary for completeness of works specified shall also deemed to be included in the scope.

1.0.4 The equipment shall be suitable for climatic conditions as indicated elsewhere in specifications. The supplier shall provide all the materials, labour, supervisory staff, plant, equipment & machinery and services necessary for accomplishing the work.

1.0.5 The scope of the vendor includes all shop tests, site tests, routine tests etc., fulfillment of complete quality assurance & inspection requirements and related activities for all the equipment & systems covered under the scope of work of vendor as per the stipulations of Technical Specifications

1.0.6

DETAILED SCOPE OF WORK:

1.0.6.1 Design, engineering, supply, erection and commissioning of all the 33kV Electrical equipment like Breaker, Isolators, Lightning arrestors, Current Transformers, Voltage Transformers, Tariff meters, and junction & marshaling boxes / cubical with all steel structure for equipment support and Gantries.

1.0.6.2 Erection and commissioning of power transformer.

1.0.6.3 Design, engineering, Supply, erection and commissioning of ACSR Conductor, insulators, Clamps and connectors.

1.0.6.5 Design, engineering, supply, erection and commissioning of Control and Relay panels for switchyard, and Battery and Battery chargers with DCDB.

1.0.6.6 Supply of 1.1 kV Control cables along with necessary lugs, glands, end termination units, nut bolts, support clamps and all accessories / hardware.

1.0.6.7 Design, laying through trays and commissioning of 11kV Power cables for Neutral Grounding resistance panel and Control cables from Switchyard equipment to Control & Relay Panels, & Neutral Grounding resistance panel and from 11kV Main Panel to Neutral Grounding resistance panel.

1.0.6.8 Design & Erection of Cable trenches inside the Switchyard.

1.0.6.9 Design & Erection of Cable Trays and Tray supports inside trenches in the Switchyard 1.0.6.10 Design, erection and commissioning of Earthing, Lightning protection and Lighting system

for switchyard.

1.0.6.11 Providing engineering data, design calculations, GA drawings including loading data, mounting arrangement along with Erection & O&M manuals for review, approval and records.

1.0.6.12 Packing and transportation from the manufacturer’s works to the site including insurance, customs clearance & port clearance, port charges, if any.

1.0.6.13 Receipt, storage, insurance, preservation and conservation of equipment at the site. 1.0.6.14 Complete switchyard structure and miscellaneous structures, switchyard fencing, and

complete civil works considering the following.

1.0.6.15 Galvanized steel structure for CB, Main bus, isolators, CT, VT & LA.

1.0.6.16 Fabrication, pre-assembly, erection, testing and putting into satisfactory operation of all the equipment/material including successful commissioning.

1.0.6.17 Satisfactory conclusion of the contract.

1.0.6.18 The Vendor shall be responsible for providing all material, equipment and services specified or otherwise which are required to fulfill the intent of ensuring operability, maintainability and the reliability of the complete work covered under this specification. 1.0.6.19 It is not the intent to specify all aspects of design and construction of equipment

mentioned herein. The systems, sub-systems and equipment shall conform in all respect to high standards of engineering, design and workmanship, and shall be capable of performing in continuous commercial operation in a manner acceptable to the Employer, who will interpret the meaning of the specification and drawings and shall have a right to

reject or accept any work or material which, in his assessment, is not complete to meet the requirements of this specification and/or applicable to Indian/ International standards mentioned elsewhere in this specification.

1.0.6.20 Whenever a material or article is specified or described by the name of a particular brand, manufacturer or trade mark, the specific item shall be understood as establishing type, function and quality desired. Products of other manufacturers may also be considered, provided sufficient information is furnished so as to enable the Employer to determine that the products are equivalent to those named.

1.0.6.21 Contractor is requested to carefully examine and understand the specifications and seek clarifications, if required, to ensure that they have understood the specifications.

1.0.6.22 Any deviation or variation from the scope requirement and/or intent of this specification shall be clearly mentioned under Deviation Schedule irrespective of the fact that such deviations/variations may be standard practice or a possible interpretation of the specification by the Vendor. Except for the deviations/variations which are accepted before the award of the contract, it will be the responsibility of the vendor to fully meet the intent and the requirements of the specification.

1.0.6.23 The drawings enclosed to this document and forming a part of the specification shall supplement the requirements specified herein. These are preliminary drawings, good for bidding purpose only and are subject to changes that may be necessary keeping the basic parameters as specified.

1.0.6.24 Failure of any equipment to meet the specified requirement of test carried out at works or at site shall be sufficient cause for rejection of the equipment. Rejection of any equipment will not be held as a valid reason for delay in the completion of the works as per schedule. Vendor shall be responsible for removing all deficiencies and supplying the equipment that meet the requirement.

1.0.6.25 The scope also includes but not limited to the following services/items described herein and elsewhere in specification:

Civil works. Structural works. Erection works.

Testing and commissioning. Interface coordination. Performance testing.

Clearances from statutory authorities.

1.0.7

ERECTION WORKS:

1.0.7.1 The Vendor shall construct, erect and install all equipment and material of switchyard covered under the contract.

1.0.7.2 Vendor shall erect and commission of power transformer, 33kV Control Panels, Neutral grounding resistance panel.

1.0.7.3 Vendor shall erect and commission lighting, lightning protection and earthing system for 33kV Switchyard.

1.0.7.4 Vendor shall be responsible for provision of all labour, tools and plant, and supervisory staff for safe, reliable, proper and correct erection of the components.

1.0.7.5 The tools and plant shall include, but not limited to, special hoisting equipment, cranes, stringing equipment, slings, consumables and all other articles and supplies as required. 1.0.7.6 The vendor shall ensure periodic cleaning of work sites and removal of all waste material,

packing material, surplus earth and left-over’s and their proper disposal.

SR. NO DETAILS 33kV SWITCHYARD

VENDOR

1 Supply of 33kV Equipment; 33kV Control Panels, 11kV ,100A neutral grounding

resistor panel.

YES

2 Erection and commissioning of 33kV Equipment; 33kV/11kV, 5 MVA Transformer, 33kV Control Panels and

11kV,100A neutral grounding resistor panel.

YES

3 Supply, Erection, Termination and Commissioning of 11kV Power Cables of

Neutral Grounding resistance panel in trays inside trenches .

YES

4 Supply, Erection, Termination and Commissioning of 1.1kV Control Cables from Switchyard to 33kV Control Panels and TR Neutral Grounding resistance

panel in trays inside trenches.

YES

5 Supply, Erection, Termination and Commissioning of Earthing system for Switchyard , 33kV /11kV Transformer,

33kV Control panel,

TR Neutral Grounding resistance panel.

YES

2.0.0 CODES AND STANDARDS:

2.0.1. Unless they are in variance with the clause of this specification the 33kV Switchyard and its components shall comply with the latest edition of the applicable standards listed below. For imported electrical equipment corresponding local codes and standards shall apply.

S.NO.

DESCRIPTION

IS/ IEEE/ IEC CODE

1 Current

Transformers

IS: 2705-1981, 1992

2 Bushings for IS: 2099-1986

Lighting system for 33kV Switchyard. YES 7 Supply, Erection, and Commissioning of

Lightning Protection system for 33kV Switchyard

YES

8 Civil, Structural and Architectural design, Erection and Construction of 33kV equipment foundation and cable trenches/

conduits inside switchyard

alternating voltages above 1000 Volts 3 Guide for selection

of insulators in Respect of pollution conditions IS: 13134 - 1992 4 Aluminum conductors aluminized Steel reinforced IS: 398 (Part-3 1976) 5 High voltage ac circuit breakers IEC: 62271

6 Common clauses for high voltage Switchgear and

control gear standards

IEC-694-1980

7 Hollow insulators for use in electrical Equipment IS: 5621 1980 9 Classification of degrees of protection Provided by enclosures of electrical Equipment IS: 12063-1987 10 LV switchgear and control gear IS: 13947-1993 11 Electric power connectors IS: 5561-1970

12 Indian Electricity Rules

1956

13 Indian Electricity Act 2003 14 Isolators and

Earthing switches

IS: 9921(Part-I) -1981

15 Porcelain Insulators IS:731-1971; IS:544-1973; IS: 5350-1969/70/73

16 Voltage

Transformers/Gener al Requirements

IS: 3156 (Part - 1) - 1992

17 IEEE Guide for Safety in A.C.

Substation Grounding

IEEE: 80-1986

18 Code of Practice for Earthing

IS: 3043-1987

20 Industrial luminaries with metal reflectors

IS: 1777-1978

21 Protection of buildings and allied

structures Against lightning

IS: 2309-1989

22 Power Transformer IEC 60076

23 Electrical relays for power system

protection

24 Specification for Lightning Arrestors(Part-III) For alternating current system IS 3070 25 Non-linear resistor type gapped surge arresters for AC

systems

IEC: 60099

26 New insulating oils IS 335 27 Measuring relays and protective equipment IEC 60255 28 30 Low voltage switchgear and control gear IEC 60947 30 - CBIP manual

2.0.2. The equipment shall also confirm to the provisions of Indian Electricity rules and other statutory requirements currently in force. In case of any contradiction between the standards listed above and this specification, the requirement laid down in this specification shall prevail.

3.0.0 SERVICE AND OPERATING CONDITIONS:

a. Maximum Ambient Temperature : 50° C b. Minimum Ambient Temperature : 22° C c. Ambient temperature for Equipment Design : 50° C

d. Relative Humidity : min -20% & max -80% e. Seismic Zone : Zone II (As per IS 1893)

f. Wind Velocity : As per IS: 875 (Part 3)

g. Highest System voltage : 36kV, 3ph, 50Hz

h. Nominal Operating Voltage : 33kV, 3Ph, 50 Hz i. Primary Distribution Voltage : 11kV, 3PH, 50Hz j. Nominal Low voltage : 415V, 3 Phase, 4-Wire k. Voltage variation : ±10%

l. Fault level : 26 kA for 1 Sec m. Operating Frequency : 50 Hz

n. Frequency variation : ±5%

o. Control voltage : 110V DC

p. Auxiliary voltage : 415/230V, 50 Hz

4.0.0

SPECIFIC REQUIRMENTS:

4.0.1 MANDATORY STATUTORY APPROVAL AND LICENSING:

4.0.1.1 Contractor shall carry out all Statutory approval and licensing work on behalf of owner with Government agencies like APTRANCO, Office of The Chief Electrical Inspector Organization, Andhra Pradesh, Chief Inspector of Factories and APPCB, Contractor requires preparing Drawings, Sizing Calculations as per prescribed format given by agencies.

4.0.1.2 Contractor needs to take authorization letter from owner and shall submit required drawings and sizing calculations to agencies in hardcopies in role of authorized contractor putting his / her signature and stamp.

4.0.1.3 Contractor need to interact with agencies and get the final approval on all schemes, drawings and sizing calculations.

4.0.1.4 Contractor shall prepare as build document and submit to Office of The Chief Electrical Inspector Organization and Factory inspector office to final approval for plant operation.

4.0.1.5 Contractor shall furnished all document / format that need to maintain during plant operation for submission to government agencies.

4.0.2

CIVIL & STRUCTURAL WORKS:

4.0.2.1 The scope of civil works shall include design & construction of all civil works & Structural for Switch Yard works including supply of all materials complete for all equipment of the Switchyard package.

4.0.2.2 Vendor shall design, construct, fabricate, supply, erect and commission foundation, main structure and support structure for 33kV equipment including 33kV Transformer, fencing, CT, CB, LA, Isolators and Towers.

4.0.2.3 The work shall generally involve earthwork in excavation and filling in all types of soils, dressing to the required profile, dewatering till the structures are constructed /erected up to required level, shoring, backfilling around completed structures and plinth filling, disposal of surplus earth, concreting including reinforcement and formwork, fabrication, galvanizing, Proto-assembly & erection of Gantry Structure & Equipment supporting structure, fabrication and erection of all structural steel and miscellaneous steel ( i.e., cable tray supports, galvanized foundation bolts etc.), breaking of concrete/ brickwork/ roads and removal of sheet piling, precast covers, RCC cable trenches, cable ducts/duct banks, soil sterilization/anti - weed treatment, drainage, fencing, gravel filling, final grading and site clearance before handing over and other auxiliary items of work etc.

4.0.2.4 All material including cement, reinforcement steel, structural steel required for completion of the work covered in the Technical specification shall be within the scope of the Contractor. 4.0.2.5 The Vendor shall provide all structures / facilities required for the effective functioning of

switchyard. The scope of vendor for Civil & Structural works shall include but not limited to the following :

a. Detailed design criteria including basis of design shall be prepared by the vendor based on various requirements specified elsewhere in the specifications. All the above documents shall be finalized after Owner’s approval and the same shall form the basis of Detailed Engineering Work.

c. Civil & structural works associated with switchyard equipment supporting structure as required.

d. Civil and structural works associated with Cable trenches from individual bays.

e. Site Preparation, soil sterilization/ant weed treatment including gravel filling but excluding major leveling.

f. Complete fencing along with gates for the switchyard.

g. All protection measures to prevent any damage to the adjoining structures / facilities.

4.0.3 PRE-COMMISSIONING AND COMMISSIONING ACTIVITIES:

4.0.3.1 The vendor's scope shall include all pre-commissioning and commissioning activities, materials and services as of Technical Specifications (Erection Conditions of Contract) including supply of all consumables, temporary equipment and piping, instruments, labor/skilled manpower etc.

4.0.4 CONSUMABLES

4.0.4.1 All the first fill and One year's topping requirements of consumable such as oil, silica gel, and essential chemicals etc. which will be required to put the equipment covered under the scope of specifications, into successful commissioning/ initial operation and to establish completion of facilities shall be furnished by the contractor.

4.0.5 SPARES:

4.0.5.1 The scope of work includes supply of mandatory spares, commissioning spares, consumable spares and others as specified under conditions of contract. Spare shall be considered for two years successful operation.

4.0.5.2 Each spare part shall be clearly marked or labeled on the outside of the packing with its description. When more than one spare part is packed in a single case, a general description of the contents shall be shown on the outside of such case; and a detailed list enclosed. All cases, containers and packages shall be suitably marked and numbered for identification.

4.0.6.1 One set of all special tools and tackles including testing, calibrating and measuring instruments required for erection, assembly, disassembly and maintenance of all equipment/ systems covered under the scope shall be supplied by the vendor.

4.0.6.2 These shall not be used for erection/ commissioning purposes and shall be in an unused and new condition, when they are handed over to the owner.

4.0.6.3 A list of all such special tools and tackles shall be submitted along with the offer.

4.0.7 PROJECT MANAGEMENT AND SITE SUPERVISION:

4.0.7.1 The vendor shall be responsible for the overall management and supervision of works. He shall provide experienced, skilled, knowledgeable and competent personnel for all phases of the contract, so as to provide the Employer with a high quality system.

4.0.7.2 The vendor shall be responsible for adequate training of owner’s operation and maintenance personnel as to be able to operate & maintain the equipment and its components properly, safely and efficiently over long period of time.

4.0.7.3 The vendor’s supervisory personnel shall provide operation and maintenance assistance during the warranty period.

4.0.7.4 A project execution schedule called in the form of PERT chart and based on `Work break down structure’ shall be prepared by the vendor for approval. The schedule shall identify milestones of key events for each work/component in the areas of engineering, procurement, manufacture, dispatch, erection and commissioning.

4.0.8 INTERFACE COORDINATION

4.0.8.1 The vendor shall identify all interface issues and shall be responsible for such interfacing, coordination and exchange of all necessary information.

4.0.8.2 The vendor shall submit to the owner all drawings for review.

4.0.8.3 He shall list the detailed requirements of interface between Contractor’s work and the material and services to be supplied by owner and other vendor.

4.0.9.1 Vendor shall make his own necessary arrangements for the following and for those not listed anywhere else:

a) Distribution/extension of the construction power supply at all works areas. b) Further distribution of construction water.

c) Construction office and store (open & covered).

d) Construction workshop and material/field testing laboratory.

e) Boarding & lodging arrangement for their personnel. I.e. contractor’s personnel. f) Fire protection and security arrangements during construction stage.

g) Suitable and adequate land/space & power supply for office, storage area, pre assembly and fabrication areas, labour and staff colony area, toilets etc.

4.0.10

DOCUMENT TO BE SUBMITTED ALONG WITH OFFER:

a) Datasheet. b) Specifications. c) Catalogue. d) GA drawings. e) QAP. f) Wiring Diagram. g) Test Certificates.

4.0.11

DOCUMENT TO BE SUBMITTED AFTER AWARD OF CONTRACT FOR

APPROVAL:

a) Design Calculations for ACSR conductors, Circuit Breakers, Isolators, LA, CT, PT, Lightning Protection, Cable tray, Steel Structures, and Switchyard Earthing. b) Layout drawings for Switchyard Equipment, Cable routing, Lighting, Lightning

Protection and Earthing.

d) Steel structure Assembly and Fabrication drawings.

e) Schedule –Control Cable with Junction & Marshaling boxes interconnection schedule.

4.0.12 TEST :

TYPE TEST:

a. All equipment to be supplied shall be of type tested quality. The vendor shall submit for approval the reports of all the type tests as listed as per relevant standard and carried out within last five years from the date of bid opening.

b. These reports should be for the test conducted on the equipment similar to those proposed to be supplied under this contract and the test(s) should have been either conducted at an independent laboratory or should have been witnessed by a owner.

c. In case the vendor is not able to submit report of the type test(s) conducted within last five years from the date of supply opening or in case the type test report(s) are not found to be meeting the specification requirements, the vendor shall conduct all such tests under this contract free of cost to the Employer and submit the reports for approval.

ROUTINE TEST:

a) All equipment to be supplied shall be of Tested for routine test as listed as per relevant standard.

b) All tests shall be carried out in presence of Owner or owner representative. Schedule of testing shall be submitted by vendor to owner before 2 week of actual date of test.

c) Equipment shall be complete in all respect like wiring, switchgears, control logics operational requirements, auxiliary system, consumables shall be present and installed at respective locations. Any short fall will not be tolerated and equipment shall not be tested.

d) Copy of test results shall be given person witnessing test at end of test with authority signatures from Contractor, OEM and Owner / owner representatives. e) Equipment shall be dispatch to owner site once dispatch certificate is issued by

owner on completion of tests.

5.0.0

CIRCUIT BREAKER:

5.0.1 INTENT :

5.0.1.1 The intent of this Section is to provide the information for the 33KV Circuit Breaker. The design, manufacture, testing and performance of Breaker shall comply in all respects with the requirements of the latest edition of the applicable standards and codes.

5.0.2 SCOPE :

5.0.2.1 The following is the scope of Supply, of the following:

a. 33kV ,Vacuum Circuit Breaker including mounting Structures: 1 Nos. b. Clamps and, Connectors : 1 Lot

5.0.2.2 The work shall be carried out in accordance with drawings, specifications and data sheets enclosed with this document.

5.0.3 GENERAL :

5.0.3.1 The design, manufacture, testing and performance of all equipment shall comply in all respects with the requirements of the latest edition of the applicable standards and codes. 5.0.3.2 The circuit breaker shall be outdoor type Vaccum circuit breaker .

5.0.3.3 One number separate 415V, 3 phase, 50Hz AC supply feeder shall be provided for local control cabinet for feeding spring charging motor and 230V, 1 phase, 50Hz AC supply for

space heaters and etc.

5.0.3.4 Breaker shall be suitable for operation from local, Relay and Control (R & C) panel .

5.0.3.5 The local controls shall include emergency hand trip devices, local/remote selector switch, local control switch and various indicating lamps etc.

5.0.3.6 All secondary and auxiliary wiring terminals shall be finger touch proof shrouded design. 5.0.3.7 The terminals of the circuit breakers shall be suitable for horizontal take off of ACSR

Conductor.

5.0.3.8 Double compression type glands of suitable size shall be supplied along with marshaling box of Circuit Breaker.

5.0.3.9 The Marshaling Boxes for equipment shall be of outdoor type with IP55 protection. The door of the cabinet shall have facility for pad locking. Provision shall be available inside the cabinet for taking single phase supply through 32A industrial metal clad power socket controlled by one 32A, MCB. The control cabinet shall be provided with suitable earthing studs of tin plated brass of suitable size for connecting to the earth grid. The control cabinet shall be provided with thermostat control space heater through MCB feeder of suitable rating.

5.0.3.10 The entire power & control network have been designed as fuse less system. Hence, no fuses shall be used in control circuits of equipment. MCBs of suitable rating and type shall be used in the control circuits (AC/DC).

5.0.3.11 The indicating lamps shall be cluster LED type. The color of lamp shall be – RED- ON, GREEN – OFF, AMBER – TRIP, BLUE – SPRING CHARGE, ORANGE / WHITE – TRIP CIRCUIT HEALTHY.

5.0.3.12 All control cabling shall be of minimum size 2.5 Sq. mm flexible multi-stranded copper, FR-PVC insulated cables.

5.0.3.13 Contact multiplication for the auxiliary contacts to be achieved only through VAJC type or static auxiliary relay and not by means of air break contactors.

5.0.3.14 CB Control switch shall be 3 position spring returns to neutral switch with 2 contacts in each of the Trip and Close positions.

5.0.4 CONSTRUCTION:

5.0.4.1 The circuit breakers shall comprise one three-phase unit or single units linked together, either mechanically or electrically. Type of execution, whether single phase or three phases shall be as specified in Data Sheet.

5.0.4.2 Circuit breakers shall be supplied with a common base and factory installed inter-phase wiring.

5.0.4.3 All similar parts, particularly removable ones, shall be interchangeable with one another. 5.0.4.4 The circuit breaker shall withstand the seismic acceleration specified.

5.0.4.5 A pole discrepancy protective scheme shall be incorporated in the circuit breaker control circuit to detect discrepancy in the instants of parting/touching of moving and stationary contacts in the three (3) poles and actuate alarm and trip circuits in the event of discrepancy persisting for durations beyond the preset times. The scheme shall be complete with time delay relay adjustable from 0.1 to 2 second, contactors etc.

5.0.5 OPERATING MECHANISM :

5.0.5.1 Circuit breakers shall be power operated by a motor charged spring operated mechanism. Main poles of the breaker shall be such that the design shall ensure a close pole spread with a maximum of 4 ms opening and 6 ms closing. The operating mechanism shall include all auxiliary devices and accessories for the type of mechanisms offered.

5.0.5.2 Operating mechanism shall utilize 415 V AC supply for closing & Tripping coils.

5.0.5.3 Circuit breakers shall feature high repeatability of absolute closing time over a wide range of parameters (ambient temperature, pneumatic pressure, control voltages, etc.). Operating mechanism shall be non-pumping electrically and either mechanically under every method of closing (except during manual closing of a breaker for maintenance). Electrical anti-pumping feature shall be obtained by means of an auxiliary relay and use of a contactor to achieve this feature shall not be acceptable.

5.0.5.4 Operating mechanism shall be suitable for high speed reclosing. It shall be non-pumping electrically and either mechanically under every method of closing (except during manual closing of a breaker for maintenance). A latch checking switch shall be provided on

mechanically trip free mechanisms to prevent reclosure before the breaker latches have reset.

5.0.5.5 Main poles shall operate simultaneously. There shall be no objectionable rebound and the mechanism shall not require any critical adjustment. It shall be strong, rigid, positive and fast in operation.

5.0.5.6 Trip coil shall be rated for not less than 200 W continuously and two numbers to be provided.

5.0.5.7 Disagreement circuit shall be provided which shall detect pole position discrepancy in case of three single phase units.

5.0.5.8 The design of the circuit breaker shall be such that contacts will not close automatically upon loss of gas.

5.0.5.9 A mechanical indicator shall be provided inside the operating mechanism box to show open and closed positions where it will be visible through a glass window to a man standing on the ground with the mechanism housing closed. An operation counter shall also be provided.

5.0.5.10 A closing release shall operate correctly at all values of voltage between 85% and 110% of the rated voltage. A shunt trip shall operate correctly under all operating conditions of the circuit breaker up to the rated breaking capacity of the circuit breaker and at all values of supply voltage between 70% and 110% of rated voltage.

5.0.5.11 Working parts of the mechanism shall be of corrosion resisting material. Bearings which require grease shall be equipped with pressure type grease fittings. Bearing pin, bolts, nuts and other parts shall be adequately pinned or locked to prevent loosening or changing adjustment with repeated operation of the breaker.

5.0.5.12 Provision shall be made for attaching an operation analyser to perform speed tests after installation of the breakers at Site.

5.0.6

SPRING OPERATED MECHANISM:

with limit switch for automatic charging and all necessary accessories to make the mechanism a complete operating unit.

5.0.6.2 As long as power is available to the motor, a continuous sequence of closing and opening operations shall be possible.

5.0.6.3 After failure of power supply to the motor, at least one open-close-open operation of the circuit breaker shall be possible.

5.0.6.4 Breaker operation shall be independent of the motor, which shall be used solely for compressing the closing spring.

5.0.6.5 Motor rating shall be such that it requires only about 30 seconds for fully charging the closing spring. Motors shall conform to Data Sheet.

5.0.6.6 Closing action of the circuit breaker shall compress the opening spring ready for tripping. 5.0.6.7 When closing springs are discharged, after closing a breaker, closing springs shall

automatically be charged for the next operation. Facility for manual charging of the closing spring shall be provided.

5.0.6.8 Mechanism shall be such that failure of any auxiliary spring shall not prevent tripping and will not cause tripping or closing operation of the power operated closing devices. When the circuit breaker is already closed, failure of any auxiliary spring shall not cause damage to the circuit breaker or endanger the operator.

5.0.6.9 Mechanical indicators to indicate charged and discharged condition of spring shall be provided. Means shall be provided to slowly open and close the breaker manually for maintenance purpose when the operating power is not available.

5.0.7

OPERATING MECHANISM CONTROL:

5.0.7.1 All accessories shall be enclosed in a weather-proof mechanism cabinet of hot dip galvanized sheet steel construction, the thickness of which shall not be less than 2 mm. 5.0.7.2 Hinged doors giving access to the mechanism at the front and sides shall be provided.

Suitable gaskets shall be provided to make the mechanism housing water-proof and dust-proof.

the breaker. A local manual closing device which can easily be operated by one man standing on the ground shall also be provided for maintenance purposes. Direction of motion of handle shall be clearly marked.

5.0.7.4 Common marshaling box with cables shall be provided. Cables from Relay and control panel will be termination in the Marshaling box.

5.0.8 BUSHINGS/ INSULATORS:

5.0.8.1 Porcelain used for the manufacture of bushing/ insulator and it shall be homogeneous, free from laminations, cavities and other flaws or imperfections that might affect the mechanical or dielectric quality and shall be thoroughly vitrified, tough and impervious to moisture.

5.0.8.2 Glazing of the porcelain shall be of uniform brown colour free from blisters, burns and similar other defects. Bushings/ insulator shall be designed to have ample mechanical strength and rigidity for the conditions under which they will be used. All bushings of identical ratings shall be interchangeable.

5.0.8.3 Puncture strength of bushings/ insulator shall be greater than the dry flashover value. When operating at normal rated voltage, there shall be no electric discharge between the conductors and bushing which would cause corrosion or injury to conductors, insulators or supports by the formation of substances produced by chemical action. No radio interference shall be caused by the bushings when operating at the normal rated voltage.

5.0.8.4 All iron parts shall be hot dip galvanized and all joints shall be airtight. Surface of the joints shall be trued-up; porcelain parts by grinding and metal parts by machining. Bushing design shall be to ensure a uniform compressive pressure on the joints.

5.0.8.5 All current carrying contact surfaces shall be silver faced. Silver facing shall not be less than one mil in thickness.

5.0.8.6 Bushings/ insulator shall satisfactorily withstand the specified insulation level.

5.0.9 BREAKER CONTACTS:

5.0.9.1 Main contacts shall have ample area and contact pressure for carrying the rated current and the short time rated current of the breaker without excessive temperature rise, which may

cause pitting, or welding.

5.0.9.2 Contacts shall be adjustable to allow for wear, easily replaceable and shall have a minimum of movable parts and adjustments to accomplish these results. Main contacts shall be the first to open and the last to close so that the contact burning and wear shall be least.

5.0.9.3 Arcing contacts, if provided, shall be the first to close and the last to open and shall be easily accessible for inspection and replacement. Tips of arcing and main contacts shall be silver faced or have tungsten alloy tipping.

5.0.9.4 Positive mechanical interconnection shall be provided between interrupting contacts, blast valve mechanism, if any, to ensure maximum operating reliability and retention timing. 5.0.9.5 If multi-break interrupters are used, they shall be so designed and augmented that a fairly

uniform voltage distribution is developed across them.

5.0.10

EARTHING :

5.0.10.1 Two clamp type earthing terminals each suitable for the clamping Owner’s earthing conductor shall be provided on each circuit breaker. Vendor shall specify min / max conductor that can be terminated.

5.0.11

STRUCTURES :

5.0.11.1 Vendor shall design, fabricate and supply the support strcture require to erect the circuit breaker.

5.0.11.2 The scope of work includes supply, fabrication, galvanizing, marking/ punching part numbers of all steel structures required for the Mounting of Equipment.

5.0.11.3 Preparation of fabrication drawings shall be Vendor’s scope.

5.0.12

NAME PLATE :

5.0.12.1 Each breaker shall be provided a name plate in English, with the following data indelibly marked on it.

a. Manufacturer’s name or trade mark. b. Serial number and type designation. c. Rated voltage

d. Rated current

e. Rated insulation level f. Rated frequency

g. Rated breaking capacities (symmetrical and asymmetrical). h. Weight (for circuit breakers) including oil/gas

i. Rated short time (for duration as specified in Data Sheet) current.

5.0.13

PAINTING:

5.0.13.1 The external finish paint shade for the Circuit Breaker, mounting structure, mechanism box and its accessories shall be Shade 631 of IS 5.

5.0.13.2 The type of paint shall be synthetic enamel air-dried.

5.0.13.3 The interior of the Control Panel / Marshaling box shall be painted with glossy white enamel paint.

5.0.13.4 All metallic parts shall have rust protection.

5.0.13.5 All steel surfaces shall be thoroughly cleaned by sand blasting or chemical agents as required, to produce a smooth surface free of scales, grease and rust.

5.0.13.6 The external surfaces, after cleaning, shall be given a coat of high quality red oxide or yellow chromate primer followed by filler coats.

5.0.13.7 Sufficient quantity of touch up paint shall be furnished for application after installation at site. 5.0.13.8 All supporting structures and hardware shall be hot dip galvanized.

5.0.14

FITTINGS & ACCESSORIES:

5.0.14.1 A list of some of the major fittings and the accessories to be furnished by the VENDOR as an integral part of the equipment.

Operating mechanism housing complete with: a. Padlocks and duplicate keys

c. Manually operated tripping push button/lever (mechanical) conveniently located to trip all three phases simultaneously.

d. Operation counter

e. Terminal boards with minimum 6 spare terminals f. Control switches to cut off control power supplies g. MCB’s as required

h. Two earthing terminals

i. Auxiliary relays required for satisfactory operation

j. Motor contactor with thermal release for spring charging motor k. Breaker local control switch

l. 3 pin 15A socket outlet and cubicle lamp m. Steel frames for frame mounted breakers

n. Manually operated device for breaker closing under failure of normal power o. Maintenance closing device

p. Foundation templates q. Foundation bolts

r. Galvanized Steel bracket for mounting current transformers s. Gas filling and filtering valve.

t. Clamps and connectors

5.0.15

SPARE PARTS :

5.0.15.1 Mandatory Spare for healthy operation of equipment and two years maintenance spare parts shall be included in offer as optional item. The item listed under (but restricted to) shall consider by vendor. In addition to following item, vendor can recommend necessary spare parts required for 2yrs of operation.

b. Main interrupter units c. Grading capacitor units d. Closing coils

e. Tripping coils

f. Accelerating and damping springs g. Spring charging motor

h. Cross head and lift rods i. Pressure switches j. Set of gaskets k. Pressure gauges

l. Local/remote changeover switch m. Bushings / Insulators (all types) n. Fixed contact assemblies o. Moving contact assemblies p. Arcing contact assemblies q. Quenching chambers r. Vacuum bottle.

s. Pressure pipe insulator t. Arcing chamber insulator u. Silica gel charge

5.0.16

DOCUMENTATION :

5.0.16.1 Bidder shall submit the following documents for equipment’s in THREE (3) SETS with the offer. a. Data Sheet.

c. Catalogues. d. Wiring Diagram. e. Test Certificates. f. Deviation List

g. Bill of material with type, ratings and makes of all components.

5.0.16.2 Vendor shall submit the following documents for all equipment after award of job for approvals:

i. Datasheet

ii. Overall general arrangement drawings giving plan, section, foundation loading data (both static and dynamic), side view, etc. in cad drawings

iii. Control and schematic diagrams with ferrule and terminal numbers. iv. Catalogue of the Equipment

v. General outline drawings showing dimensions, net and shipping weights, quantity of SF6 / air receiver capacity, etc.

vi. Internal component layout drawings.

vii. Sectional views showing the general constructional features of the circuit breaker including operating mechanism, arcing chambers, contacts, Vacuum bottle, with bushing lifting dimensions.

viii. General arrangement of the foundations or structure mountings in CAD. ix. Instruction and Training Manual

x. Packing drawings and Packing list xi. Equipment Storage

xii. QAP

5.0.17

TEST :

All routine tests as per applicable standard shall be carried out on each circuit Breaker without any extra charges.

a. Insulation resistance test b. Millivolt drop test

c. Connections test d. Overload tripping test e. Mechanical operation

f. Measurement of opening and closing time g. Tightness test

h. Electrical operation i. Physical dimension check

j. Primary and secondary injection test 5.0.17.2

TYPE TEST

a. Impulse test

b. Power frequency withstand test c. Heat run

d. Making capacity and breaking capacity test e. Short circuit test

f. Mechanical endurance g. Electrical endurance h. Ingress protection

5.0.17.3 Vendor shall submit report for type test list above. The test shall be conducted on same make, model and configuration of equipment offered. The reports shall not older than 5 years from date of supply. If report do not comply the above requirement, vendor need to perform the test on one equipment without any cost or time implication.

6.0.0

33 kV ISOLATORS :

6.0.1

INTENT :

6.0.1.1 The intent of this specification is to provide the information for the 33 kV Isolator. The design, manufacture, testing and performance of isolator & its equipment shall comply in all respects with the requirements of the latest edition of the applicable standards and codes.

6.0.2

SCOPE OF SUPPLY :

6.0.2.1 The following is the scope of Supply, of the following :

a) 33kV Isolator with one earth switches including mounting Structures 2 Nos. b) 33kV Isolator without earth switches including mounting Structures 1 Nos c) Aluminium alloy connectors for 33kV Isolator pad to ACSR

Conductor

6.0.2.2 The work shall be carried out in accordance with drawings, specifications and data sheets enclosed with this document.

6.0.3

CONSTRUCTIONAL FEATURES:

6.0.3.1 The isolator/earthing switch shall be complete with all parts that are necessary or essential for efficient operation. Such parts shall be deemed to be within the scope of supply, whether specifically mentioned or not.

6.0.3.2 All similar parts shall be interchangeable.

6.0.3.3 Base channels and other structural steel members such as operating pipes, phase coupling rods etc. operating mechanism boxes, bolts, pins etc., shall be dip galvanized or metallized. All castings except current carrying parts shall be made of galvanized steel.

6.0.3.4 Live metal parts shall be of non-rusting and non-corroding metal. Current carrying parts shall be of non-ferrous materials such as aluminum or copper, but copper silicon alloy shall be avoided. Bolts, screws and pins shall be provided with lock washers, keys or equivalent locking facilities.

6.0.3.5 The isolator design shall be such that it is free from visible corona discharge in both closed and open positions at the visible discharge test voltages as per applicable standards. Necessary stress relieving rings or shields shall be provided to meet this requirement.

6.0.3.6 Isolators and earthing switches including their operating mechanism shall be such that they cannot be dislodged from their open or closed positions by gravity, wind pressure, vibrations, shocks or accidental touching or seismic forces or breaking or the connecting rods or the operating mechanism.

6.0.3.7 The design shall be such that no lubrication of any part is required except at very infrequent intervals.

6.0.3.8 During the course of normal operation, it is likely that the isolator/earth switch may be left in the Open/Closed position for long periods of time. They shall be designed to operate satisfactorily even after being kept in one position for long periods.

6.0.3.9 The isolator or earthing switch shall be provided with high current carrying contacts on the hinge and jaw faced copper.

6.0.3.10 The isolators and earth switches shall be designed to withstand stresses corresponding to specified short circuit duties.

6.0.3.11 The insulators shall withstand the seismic force level given.

6.0.4 ACCESSORIES :

a) Position Indicator:

A mechanical position indicating device shall be provided for each isolator/earthing switch, irrespective of whether the isolating distance is visible or not.

b) Earthing Pads:

Each pole of the isolator shall be provided with earthing pads of non-corrodible material, brazed to the channel base. Flexible copper earth connectors shall be provided for connecting operating handles of isolators and earthing system.

These shall be provided for counter balancing the isolators to prevent impact at the end of travel both on opening and closing of the isolator/earthing switch. The springs shall be non-rusting alloy.

6.0.5

NAME PLATES :

6.0.5.1 A weatherproof and corrosion-proof nameplate shall be provided on isolators, earthing switches and operating devices. The nameplate shall conform to applicable standards. 6.0.5.2 Adequately rated, renewable type arcing tips shall be provided on the isolators to make

and break the magnetizing or line/bus charging currents.

6.0.6

EARTHING SWITCH:

6.0.6.1 Earthing switch shall form an integral part of each pole of the isolator. Two independent earthing pads each with flexible copper braids and suitable connection for the specified size of earth conductor lead shall be provided at the hinge end of the switch.

6.0.7

INTERLOCKS:

6.0.7.1 Isolators and earthing switches shall be provided with padlocking facility to lock them in fully open or fully closed positions. Padlocks shall be supplied with the isolators.

6.0.7.2 Isolator and earthing switches shall be mechanically interlocked such that it will not be possible to close the earthing switch when the isolator is closed and vice-versa.

6.0.7.3 Isolator shall be provided with electrical interlocking feature. This shall be in the form of bolt interlock comprising an interlock coil of latch-in type to lock the isolator-driving shaft and hence prevent isolator operation in the latch in condition. It shall be possible to release the latch by energizing the interlock coil when certain pre-set conditions of interlocking scheme are fulfilled. For this purpose the VENDOR shall provide facilities for wiring external interlocking contacts both in isolator opening and closing circuits. Further, a separate bypass switch shall be provided on the local control cabinet to facilitate emergency manual operation of isolator.

6.0.7.4 Electrical interlocking arrangement shall be fail less safe type.

6.0.7.5 Isolator shall be provided electrical interlocking facility with upstream breaker. 6.0.7.6 The isolator shall have min following interlock but not limited to –

i. Isolator shall not able to close when breaker is closed. ii. Isolator shall not able to open when breaker is closed.

iii. Isolator shall able to close or open only when breaker is open and earthing switch is Closed.

iv. Earthing switch shall not able to close when Isolator is closed.

6.0.8

INSULATORS :

6.0.8.1 Porcelain used for the manufacture of insulators and it shall be homogeneous, free from flaws or imperfections that might affect the mechanical or dielectric quality. They shall be thoroughly vitrified, tough and impervious to moisture. The glazing of the porcelain shall be of uniform brown colour, free from blisters, burns and other similar defects. Insulators of the same rating and type shall be interchangeable.

6.0.8.2 The porcelain and metal parts shall be assembled in such a manner that any thermal expansion differential between the metal and the porcelain parts throughout the range of temperature variation shall not loosen the part or create undue internal stresses which may affect the electrical mechanical strength and rigidity. Each cap and base shall be of high-grade cast steel or malleable steel casting and they shall be machine faced and smoothly galvanized. The cap and base of the insulators shall be interchangeable with each other.

6.0.9

OPERATING MECHANISM AND CONTROLS:

6.0.9.1 The operating mechanism shall provide quick, simple and effective operation. Time of operation shall not exceed 12 seconds. One man shall be able to operate the isolator/earthing switch (when manually operated) without undue effort.

6.0.9.2 The ganging mechanism shall be provided with sufficient adjustment to allow for Final alignment of the isolator blades for simultaneous operation. Adjustable stops shall be provided to prevent over travel in either direction.

6.0.9.3 The isolator shall be provided with positive continuous control throughout the entire cycle of operation. The operating pipes and rods shall be sufficiently rigid to maintain positive control under most adverse conditions and when operated in tension or compression for

isolator closing. They shall also be capable of withstanding all torsional and bending stresses due to operation of the isolator.

6.0.9.4 It shall not be possible, after final adjustment has been made, for any part of the Mechanism to be displaced at any point in the travel sufficiently to allow improper functioning of the isolator when the isolator is opened or closed at any speed. All holes in cranks, linkages etc., having pins shall be drilled to accurate fit so as to maintain the minimum amount of slack and lost motion in the entire mechanism.

6.0.9.5 The manual operating handles shall be mounted on the base of supporting structure. Guide bearings shall be provided if necessary at a height of 750mm above grade level. All brackets, angles, guides, guide bearings or other members necessary for attaching the operating mechanism and operating handles supporting structure and foundations shall be supplied as an integral part of the isolator. Rustproof pins and bearings of the bronze bushing, ball and roller type, shall be furnished. All bearings shall be weather protected by means of covers and grease retainers. Bearing pressures shall be kept low to ensure long life and ease of operation.

6.0.9.6 The operating mechanism design shall be such that during the operation of the isolator (especially manual operation) the moving blades once they reach the sparking distance, springs shall take over to give a quick, snap action enclosing so that the isolator closing is independent of manual efforts. Similarly, the springs must assist during the opening operation to give quick breaking feature.

6.0.10 INSULATION LEVELS :

6.0.10.1 The rated insulation levels shall be in accordance with the applicable standards.

6.0.11 TEMPERATURE RISE :

6.0.11.1 The temperature rises of any part of the isolator and associated equipment shall not exceed the maximum permissible temperature rise values as stipulated in the applicable standard, corresponding specified design ambient temperature.

6.0.12 CLAMPS AND CONNECTORS:

6.0.12.1 Clamps and connectors shall be supplied as a part of the isolator.

6.0.13 SHORT CIRCUIT REQUIREMENTS :

6.0.13.1 The rated peak short-circuit current or the rated short time current carried by an isolator or earthing switch for the rated maximum duration of short circuit shall not cause:

a. Mechanical damage to any part of the isolator or earthing switch. b. Separation of the contacts or contact welding; and

c. A temperature rise likely to damage insulation.

6.0.13.2 After the passage of these currents, the isolator shall be able to carry its rated current under specified conditions and the operation of the operating device shall not be impaired.

6.0.13.3 The rated peak short circuit current and the rated short time current, of the earthing switch shall be at least equal to those specified for the isolator. The earthing switch shall be capable of making on a dead short circuit without damage of endangering the operator.

6.0.14

SUPPORTING STRUCTURES:

6.0.14.1 Supporting structures for isolator and earthing switches are included in the VENDOR’S scope of supply. The VENDOR shall furnish detailed dimensioned drawings indicating weights and all fixing details and relative locations of chassis, operating mechanism box and operating handles. Final responsibility for ensuring that mounting and supporting arrangements of isolator are proper and that there is no interference of any part of the isolator with supporting structures rests with the VENDOR.

6.0.14.2 The mounting heights indicated in Data Sheet/ Layout are only tentative and are likely to vary within +25%. This will be confirmed at the time of the drawing approval.

6.0.15

DOCUMENTATION:

6.0.15.1 Vendor shall submit the following documents for all equipment along with offer a) Data Sheet.

c) Catalogues. d) Wiring diagram. e) Test certificates. f) Deviation List.

6.0.15.2 Vendor shall submit the following documents for all equipment after award of job for approvals:

a) GA Drawing with Termination details b) Filled datasheets

c) Quality plan.

d) Foundation layout drawing. e) Erection drawings.

f) Control Schematic g) Wiring Diagrams

h) Shipping drawing showing the dimensions and weights i) Packing list

j) O&M manual of the transformer k) Catalogues.

6.0.16 TEST

:

6.0.16.1 All routine tests specified in relevant IS and IEC standards need to perform on each isolator. 6.0.16.2 All routine tests shall be performed in presence of Owner engineer or their representative. 6.0.16.3 The equipment offered shall be furnished with all type test report as per relevant IS and IEC

standards. The certificates shall not be older than 5 years from date of supply. Any absence of certificate or certificate older than 5 year will ask to perform the test on equipment. All such test shall perform without any extra cost and time. All tests shall be made on completely assembled isolators, earthing, switches, their operating devices and auxiliary equipment.

7.0.0

BUSBAR:

7.0.1

INTENT:

7.0.1.1 The intent of this Section is for the ALUMINIUM CONDUCTOR STEEL REINFORCED (ACSR) Conductor. The design, manufacture, testing and performance of ACSR Conductor shall comply in all respects with the requirements of the latest edition of the applicable standards and codes.

7.0.1.2 The exact quantity shall be decided by vendor based on actual site condition and handling.

7.0.2 SPECIFIC REQUIREMENTS:

7.0.2.1 WIRE SIZE

a. Nominal Size

The aluminium and galvanised steel wires for the stranded conductor covered by this standard shall have Suitable diameters. The diameter of the galvanized steel wires shall be measured over the zinc coating.

b. Tolerance on Normal Size

i. Aluminium Wires: No negative tolerance shall be permitted on the nominal diameter of Al wires. However, the diameter as per IS: 398 (part-2) amended up to date. ii. Galvanised Steel Wires: A tolerance of +/- 2 % is permitted on the nominal

diameter.

7.0.3 FREEDOM FROM DEFECTS:

7.0.3.1 The wires shall be smooth and free from all imperfections such as spills, splits, slag inclusion, die marks, scratches, fittings, blow-holes, projections, looseness, overlapping of strands, chipping of aluminium layers etc. and all such other defects which may hamper the mechanical and electrical properties of the conductor. Special care should be taken to keep away dirt, grit etc. during stranding.

7.0.4 JOINTS IN WIRES:

of the ACSR conductor. Joints in the inner layers are permitted, in addition to those made in the base rod or wire before final drawing, but no two such joints shall be less than 15 metre apart in the complete stranded conductor. Such joints shall be made by cold pressure butt- welding.

7.0.4.2 Joints are not permitted in the outermost layer of the conductor in order to ensure a smooth conductor finish.

7.0.4.3 Galvanized Steel Wires: There shall be no joints except those in the base rod or wire before final drawing, in steel wires forming the core of the steel re-inforced Aluminium conductor. 7.0.4.4 Joints are not permitted in the steel wires after final drawing in order to avoid reduction in

the breaking strength of the conductor that may occur as a result of failure of the joints.

7.0.5 STRANDING:

7.0.5.1 The wires used in the construction of galvanized steel reinforced Aluminium conductor shall before stranding, satisfy all the relevant requirements of this specification.

7.0.5.2 While stranding, pre forming and post forming method should be used for stranded steel core. In order to relieve the residual tension in core wire to avoid flaring of conductor.

7.0.5.3 In all constructions, the successive layers shall have opposite directions of lay, the outermost layer being right-handed. The wires in each layer shall be evenly and closely stranded.

7.0.5.4 In conductors having multiple layers of Aluminium wires, the lay-ratio of any Aluminium layer shall not be greater than the lay-ratio of Aluminium layer immediately beneath it.

7.0.6 CONDUCTOR DRUM

:

7.0.6.1 The conductor shall be supplied in non-returnable strong wooden drums provided with lagging of adequate strength and displacement during transit, storage and subsequent handling and stringing operation in the field. The drums shall generally conform to IS: 1778. 7.0.6.2 Each drum shall stenciled on in indelible ink for Name and address of consignee,

Manufacturer’s name and address, Drum Number, Size of Conductor, Length of Conductor in meters, Gross weight of drum with Conductor, and Arrow marking for unwinding.

paper shall be secured to the drum barrel and inside of flanges or the drum by means of a suitable commercial adhesive material. The paper should be dried before use. Medium grade craft paper shall be used in between the layers of the conductor.

7.0.6.4 After reeling the conductor, the exposed surface of the outer layer conductor shall be wrapped with thin polythene sheet across the flanges to preserve the conductor from dirt, grit and damage during transportation and handling and also to prevent ingress of rain water during storage/transport.

7.0.6.5 The conductor ends shall be properly sealed and secured with the help of nails or bolts on one side of the flanges to avoid loosening of conductor layers in transit and handling.

7.0.7.1

DOCUMENTATION:

7.0.8.1 Vendor shall submit the following documents for all equipment along with offer: i. Data Sheet.

ii. Typical cross-sectional details iii. Catalogues.

iv. Wiring diagram. v. Test certificates. vi. Deviation List

7.0.8.2 Vendor shall submit the following documents for all equipment after award of job for approvals:

i. Filled datasheets ii. Quality plan.

iii. Shipping drawing showing the dimensions and weights. iv. Termination details, Bending Details

v. Catalogues vi. O&M manual

7.0.7 TEST

ROUTINE TESTS:

All routine tests as per applicable standard shall be carried out in presence of engineer form owner or their representative without any extra charges.

a. Check to ensure that the joints are as per specification. b. Check that there are no cuts etc. on the strands. c. Check that drums are as per specification.

d. All acceptance tests mentioned as above shall be carried out on each coil and the record of the same shall be kept by the supplier and same shall be produced at the time of inspection.

e. Resistance Test

TYPE TESTS:

The following Type Tests shall be conducted a. Test for surface condition

b. Test for ultimate breaking load on stranded conductor.

If vendor can furnished the Type Test certificate for test conducted not 5 years before date of supply, the type test can be waived off. Any failure of submission of certificate or certificates older than 5 yrs., vendor need to perform the test without extra cost and time.

8.0.0 LIGHTNING ARRESTOR:

8.0.1 INTENT:

8.0.1.1 The intent of this Section is to provide the information for the 30 kV Lightning Arrester .The design, manufacture, testing and performance of all equipment shall comply in all respects with the requirements of the latest edition of the applicable standards and codes.

8.0.2

SCOPE:

8.0.2.1 The following is the scope of Supply, of the following :

b. Clamps, and Connectors 1 Lot.

8.0.2.2 The work shall be carried out in accordance with drawings, specifications and data sheets enclosed with this document.

8.0.3

GENERAL REQUIREMENTS :

8.0.3.1 The LA's shall be supplied with insulating base to monitor the discharge currents. 8.0.3.2 Each LA shall be supplied with one discharge counter and leakage current indicator.

8.0.3.3 The discharge counter shall be provided with M12 tin plated brass studs with two nuts, brass washers & spring washer for connections to Purchaser’s earth grid. Suitably rated bypass shunt for bypassing the discharge counter shall also be provided.

8.0.3.4 The discharge counter shall be suitable for outdoor installation with IP55 protection.

8.0.3.5 The insulated flexible connector required for connecting LA to the discharge counter is in the scope of the bidder.

8.0.3.6 The flexible connectors shall be of adequate length with margin.

8.0.3.7 The LA will be connected to ACSR conductor. The terminals shall be suitable for vertical takeoff and clamps and connectors shall be indicated in Data sheet.

8.0.3.8 The materials and components not specifically stated in this specification but which are necessary for satisfactory operation of the equipment are deemed to be included in the scope of supply unless specifically excluded.

8.0.4

CONSTRUCTIONAL FEATURES:

8.0.4.1 Lightning arrestors shall be of the hermetically sealed type of self-supporting Construction, suitable for mounting on the steel structures.

8.0.4.2 They shall have adequate thermal discharge capacity for severe switching surges, long duration surges and multiple strokes. The lightning arrestors when provided with pressure relief devices shall be capable of withstanding the internal pressures developed during the above discharges without operation of the pressure relief devices..

8.0.4.3 Spacers for gaps and valve elements or valve blocks shall be of ceramic material. These shall be provided in such a way as to obtain robust construction, with excellent mechanical and electrical properties.

8.0.4.4 Outer insulators shall be of porcelain having adequate mechanical strength and rigidity, for satisfactory operation under climatic conditions obtaining at Site. Porcelain shall be finely glazed and shall be free from imperfections.

8.0.4.5 Arrestors shall be designed to withstand seismic acceleration and wind pressure as specified. 8.0.4.6 Arrestors shall incorporate anti-contamination feature to prevent arrestor failure,

consequent to uneven voltage gradient across the stack in the event of contamination of the arrestor porcelain. These features shall be described in detail when submitting the Bid.

8.0.4.7 Arrestors shall be suitable for hot line washing.

8.0.4.8 All metal parts shall be of non-rusting and non-corroding metal. Bolts, screws and pins shall be provided with lock washers, keys or equivalent locking facilities. All similar parts, particularly removable ones, shall be interchangeable.

8.0.4.9 Arrestors shall be capable of spark over on frequent switching surges.

8.0.4.10 Arrestors shall be capable of discharging over-voltages occurring during switching of unloaded transformers, capacitor banks and long lines.

8.0.5

ACCESSORIES :

8.0.5.1

SUPPORTING ARRANGEMENT:

8.0.5.1.1 Arrestors shall be complete with insulating boxes having provision for bolting to flat surface of supporting structure. Steel Supporting structure is part of the scope of supply of the VENDOR. The VENDOR shall furnish detailed dimensional drawings indicating all fixing details and electrical clearance diagram for installation.

8.0.6

DISCHARGE COUNTER:

8.0.6.1 Self-contained discharge counter, suitably enclosed for outdoor use and requiring no auxiliary or battery supply shall be provided for each single pole unit.

8.0.6.2 The discharge counter shall be visible through an inspection window.

8.0.6.3 The counter terminals shall be robust and shall be so located that incoming and outgoing connections are made with minimum possible bends.

8.0.6.4 Suitably sized bypass shunts of copper to facilitate bypassing the discharge counter shall be furnished. The design of the terminal connectors shall permit the connection of these shunts. 8.0.6.5 The connecting conductor from lightning arrestor earth terminal to the discharge counter

incoming terminal shall be insulated for a minimum of 4 kV and this insulated conductor shall be supplied along with the arrestor by the VENDOR. This insulating conductor shall be of the type which does not require sealing ends or plumbed joints at its either end for terminations. 8.0.6.6 A leakage current detector as an integral part of the discharge counter shall be supplied.

The counter along with the detector shall be so arranged that it will be possible to read the leakage current values from ground level. The value of leakage current beyond which the operation is abnormal shall be clearly marked in red colour on the detector.